Dissertationen: „Macroalgue“

1

Greff, Stéphane. „Métabolomique, effets biologiques et caractère invasif de la macroalgue Asparagopsis taxiformis“. Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4358/document.

Der volle Inhalt der Quelle

Annotation:

Considérées comme des menaces pour les écosystèmes marins tropicaux et subtropicaux, les proliférations de macroalgues sont susceptibles de modifier le fonctionnement et la structure des récifs coralliens. Le genre Asparagopsis (Rhodophyta) est connu pour être largement distribué, introduit et parfois invasif dans certaines régions comme en Méditerranée occidentale. Le premier objectif était de corréler le métabolisme spécialisé et la bioactivité de l’algue à son génotype, et éventuellement à son caractère proliférant. Aucune corrélation génétique/métabolomique n’a été démontrée, ce qui laisse entendre que le métabolisme macroalgal serait principalement influencé par l'environnement et/ou sa flore microbienne associée. En milieu tempéré, A. taxiformis et A. armata présentent des signatures métabolomiques globalement similaires et associées à une bioactivité significativement plus importante qu'en milieu tropical. Cependant, même lorsqu’elle a été introduite, une même lignée génétique et un même phénotype chimique peuvent présenter des caractères proliférants opposés. En milieu tropical, les extraits de macroalgues testés in situ sur 4 espèces de coraux n'ont provoqué que de faibles blanchissements. En milieu tempéré, aucun effet biologique de l’algue n’a été enregistré sur le corail Astroides calycularis. Par contre des expériences en aquarium ont permis de montrer qu’A. taxiformis pouvait exprimer un métabolisme spécifique avec une bioactivité augmentée après 10 jours de contact avec ce corail. En conclusion, qu’elle soit indigène ou introduite, A. taxiformis exerce peu d’effets sur la santé des coraux, et le caractère invasif de cette algue reste une source de débat
Considered as a major threat for sub–tropical and tropical ecosystems, macroalgal proliferations are susceptible to modify the structure and the functioning of coral reefs. The genus Asparagopsis (Rhodophyta) is known to be widespread, introduced and sometimes invasive in certain regions such as the Western Mediterranean Sea. The first objective of this thesis was to correlate the algal specialized metabolism and its bioactivity with its genotype, and eventually with its proliferation trait. No correlation between genetics and metabolomics has been demonstrated, which would suggest the main influence of environmental factors and/or the associated microbial diversity on the algal metabolism. In temperate regions, A. taxiformis and A. armata showed similar metabolomic fingerprints with bioactivities significantly higher than in tropical regions. However, even when it is introduced, a given genetic lineage and a given chemical phenotype can exhibit opposite proliferative traits. In tropical areas, algal extracts tested in situ on 4 coral species did not lead to any coral bleaching. In temperate areas, no biological effect of the alga was recorded on Astroides calycularis. However, some aquarium experiments allowed to show that A. taxiformis can express a specific metabolism, with an increased bioactivity after 10–days of contact with this coral. To conclude, either indigenous or introduced, A. taxiformis poorly affects corals’ health, and thus the invasiveness of this alga remains a matter of debate

APA, Harvard, Vancouver, ISO und andere Zitierweisen

2

Garcia, Bueno Nuria. „Valorisation de la macroalgue proliférante Grateloupia turuturu dans l'élevage de l'ormeau européen Haliotis tuberculata“. Nantes, 2015. http://archive.bu.univ-nantes.fr/pollux/show.action?id=8a5546e0-7d93-4de3-93cb-8783c4bc12fd.

Der volle Inhalt der Quelle

Annotation:

L'ormeau Haliotis tuberculata, dont l'aquaculture est peu développée en Europe, apparaît comme un candidat potentiel pour la diversification des activités conchylicoles. Cependant, sa production rencontre deux principales limites. Tout d'abord, l'approvisionnement des élevages en nourriture de qualité constituent une dépense majeure des entreprises. De plus, ces dernières années, les populations naturelles tout comme les élevages ont subi de fortes mortalités liées à la bactérie pathogène Vibrio harveyi. Par son caractère prolifératif, l'algue rouge Grateloupia turuturu, présente sur la côte atlantique, constitue une biomasse disponible qui pourrait être valorisée pour l'aquaculture de l'ormeau. En effet, Grateloupia turuturu dispose d. Une composition biochimique intéressante pour la croissance de l'ormeau qui montre une nette préférence pour les algues rouges. Des tests d'alimentation on été réalisés en élevage. Il apparait que cette algue n'est pas utilisable à l'état frais comme aliment principal mais pourrait constituer un complément alimentaire. De plus, il a été récemment mis en évidence que cette espèce présente une activité antibactérienne. Cette activité a été confirmée in vivo et in vitro sur la souche pathogène ORM4 de Vibrio harveyi
Abalone Haliotis tuberculata, which farm production is not well developed in Europe, seems a potential candidate for the diversification of shellfish aquaculture. However, its production faces two main limitations. First, the supply of livestocks in quality food are a major expense for enterprises. Second, in recent years, natural populations as well as livestocks have suffered high mortalities related to the pathogenic bacterium Vibrio harveyi. Because of its proliferative nature, red seaweed Grateloupia turuturu, present on the Atlantic coast, constitute represent an available biomass that could be valorized in abalone aquaculture. Indeed, Grateloupia turuturu presents a biochemical composition that could be of interest for abalone. S growth. This species shows a clear preference for red seaweeds. Nutritional tests have been made on livestocks. It appeared that seaweed cannot be used fresh as main feed but it could be a dietary supplement. In addition, it has recently been demonstrated that this species has an antibacterial activity. This activity was confirmed in vivo and in vitro using the pathogenic strain of Vibrio haveyi ORM4

APA, Harvard, Vancouver, ISO und andere Zitierweisen

3

Paix, Benoît. „Etude des dynamiques spatio-temporelles des interactions entre le microbiote et le métabolome de surface de la macroalgue Taonia atomaria par une approche multi-omiques“. Electronic Thesis or Diss., Toulon, 2020. http://www.theses.fr/2020TOUL0012.

Der volle Inhalt der Quelle

Annotation:

En tant qu’espèces ingénieures de leurs écosystèmes et que producteurs primaires, les macroalgues marines jouent un rôle crucial au sein de leur écosystème. Les interactions chimiques avec leurs microorganismes épiphytes semblent particulièrement essentielles pour leur physiologie. Cependant les relations macroalgues-microbiote et le rôle des paramètres environnementaux dans ces interactions restent encore peu explorées. L’objectif général de la thèse est de comprendre comment varie la structure de la communauté procaryotique épiphyte de l’algue brune Taonia atomaria en lien avec les variations de la production métabolique de surface de l’hôte et quelle est l’influence de l’environnement sur ces variations qui affectent et façonnent ce modèle d’holobionte. Une approche multi-omiques, couplant l’étude des communautés procaryotes épiphytes par metabarcoding et l’étude des métabolites de surface par des analyses optimisées en métabolomique, a ainsi été employée conjointement avec d’autres analyses telle que la cytométrie en flux. Les résultats obtenus ont révélé que la communauté microbienne épiphyte de T. atomaria, lui était spécifique en comparaison avec les communautés de biofilms de substrats rocheux et celles planctoniques, suggérant un rôle possible du métabolome de surface. Entre outre, d’importantes co-variations entre le métabolome et le microbiote à la surface de l’algue ont été observées à différents niveaux, que ce soit à l’échelle du thalle, de la dynamique temporelle ou encore d’un point de vue biogéographique. Certains paramètres environnementaux semblent être particulièrement impliqués dans les interactions au sein de l’holobionte, tels que la température, la contamination en cuivre, mais aussi l’intensité lumineuse. Dans un contexte de Changement Global, ces travaux apportent de nouvelles perspectives permettant de mieux appréhender la dynamique des macroalgues-holobiontes
As ecosystems engineers and primary producers, marine seaweeds play important roles for other organisms. Chemical interactions with epiphytic microorganisms seem particularly important for their physiology. However, macroalgae-microbiota relationships and the role of environmental parameters remains poorly investigated. The main objective of this PhD thesis was to understand how vary the epiphytic prokaryotic community of the brown alga Taonia atomaria, in relationship with variations of the surface metabolome of the host and what is the influence of the environment on these variations which shape this holobiont model. A multi-omics approach coupling prokaryotic communities studies by metabarcoding and surface metabolites studies by an optimized metabolomics analysis, has been jointly conducted, together with further analyses such as flow cytometry. Studies have thus revealed that the epiphytic microbial community of T. atomaria was specific in comparison with the biofilm communities of rocky substrates, and planktonic ones, suggesting a possible role of the surface metabolome in the structuring of the microbiota. Otherwise, important co-variations between the metabolome and the microbiota at the algal surface were observed at different levels, whether at the thallus or biogeographical scale, or during temporal dynamics. Some environmental parameters seem to be particularly involved in these interactions, such as temperature, copper contamination, but also irradiance. In a context of Global Change, this work provides new perspectives allowing to better understand dynamics of macroalgal-holobionts

APA, Harvard, Vancouver, ISO und andere Zitierweisen

4

Bréchignac, François. „Photosynthèse et photorespiration chez la macroalgue marine Chondrus crispus : substrat carboné absorbé et nature de la prise d'oxygène“. Paris 7, 1985. http://www.theses.fr/1985PA077013.

Der volle Inhalt der Quelle

Annotation:

Conçu pour le milieu aquatique, un dispositif expérimental permet la quantification continue et en conditions contrôlées de la photosynthèse, de la photorespiration et de la respiration chez la macroalgue marine Chondrus crispus (Rhodophycées, Gigartinales). Mesurée au moyen d'une colonne d'échanges, l'évolution de la concentration en CO₂ dissous en régime stationnaire indique l'existence d'une importante résistance aux transferts de CO₂ à l'interface air-eau, et l'absorption préférentielle du carbone inorganique externe sous forme HCO⁻₃. La forte affinité apparente de la photosynthèse pour le CO₂ (Km (CO₂) ≃ 1 µM) est la conséquence de l'absorption directe de HCO⁻₃ laquelle concentrerait le carbone inorganique dans l'espace intracellulaire. Mesurée par la méthode à 1'18O₂, la photoconsommation d'O₂ présente une faible amplitude en conditions standard, peu de sensibilité au CO₂ et une vitesse supérieure à la respiration nocturne quand le CO₂ est sursaturant. Elle s'avère par ailleurs sensible à 1'O₂ (Km (O₂) ≃ 4 à 16%), comme la photosynthèse nette (40 à 70% d'effet Warburg), quand la concentration n'excède pas 30%. Suggérée par ces résultats, la nature composite de la photoconsommation d'O₂ est confirmée par l'influence de l'intensité lumineuse, de la température et de quelques inhibiteurs : maintien sous lumière de la respiration mitochondriale, implication de la voie du glycolate à 45% au mieux dans la prise totale d'O₂, qui résulte alors surtout de la réaction de Mehler, voire d'une chlororespiration.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

5

Sayed, Walaa. „Évaluation des potentialités d’une filière de macroalgues vertes cellulosiques pour la production de bioéthanol“. Rennes, Ecole nationale supérieure de chimie, 2017. http://www.theses.fr/2017ENCR0044.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

6

Boulho, Romain. „Application de procédés éco-responsables pour l’extraction de molécules de la macroalgue Solieria chordalis, caractérisations chimiques et étude d'activités biologiques“. Thesis, Lorient, 2017. http://www.theses.fr/2017LORIS465/document.

Der volle Inhalt der Quelle

Annotation:

Ce projet de thèse a été réalisé au sein du Laboratoire de Biotechnologie et Chimie Marines. Ce travail est le fruit d’une collaboration au niveau régional avec deux entreprises morbihannaises Armen Instruments et Newonat et au niveau international avec l’institut de recherche CINVESTAV au Mexique. Solieria chordalis (Rhodophyta, Gigartinales) est une algue proliférante de la côte de Bretagne sud. Cette algue s’échoue chaque année sur la presqu’île de Rhuys dans le Morbihan, et représente une biomasse importante encore sous exploitée. Les objectifs de cette thèse portent sur l’application de différents procédés éco-responsables (CO2 supercritique, Extraction Assistée par Enzyme et Extraction Assistée par Microondes) utilisés pour l’extraction de molécules à partir de S. chordalis. Dans le cadre de la première partie, l’extraction assistée par microondes a permis la production d’extraits polysaccharidiques de faibles poids moléculaires non cytotoxiques dont l’efficacité antivirale est supérieure à celle observée pour les fractions obtenues après extraction aqueuse à haute température. La deuxième partie concerne le couplage de différents procédés : Extraction Assistée par Enzymes (EAE), CO2 supercritique et Extraction Assistée par Microondes (EAM). En fonction des procédés utilisés, différentes familles de molécules ont pu être caractérisées. Le couplage de procédés permet de proposer un schéma de bioraffinage. La dernière partie porte sur l’optimisation d’une méthode de fractionnement par Chromatographie de Partage Centrifuge (CPC). Ce système de purification innovant a conduit à l’isolement de composés naturels dont des Mycosporines-like Amino Acids ayant différentes propriétés valorisables dans le domaine de la cosmétique. Ces travaux enrichissent les connaissances sur l’algue S. chordalis et ouvrent la voie à la valorisation de cette biomasse proliférante sur les côtes bretonnes
This thesis has been carried out within the Laboratoire de biotechnologie et Chimie Marines. Theproject is an outcome of the collaboration of two regional companies, Armen Instruments and Newonat with an international research institute, CINVESTAV, Mexico. The red algae, Solieria chordalis (Rhodophyta, Gigartinales) is a proliferative seaweed native in the southern coast of Brittany. Every year, on the Rhuys peninsula in Morbihan, S. chordalis grows abundantly which represents a large amount of biomass, being still unused. The aim of this project, focused on the application of different ecofriendly processes (Supercritical carbon dioxide, Enzymatic Assisted Extraction and Microwave Assisted Extraction) used for the extraction of biocompounds from S. chordalis. Under the first part, the Microwave Assisted Extraction allowed to produce low molecular weight polysaccharide extracts with no cytotoxicity. These extracts showed an improved antiviral efficiency compared to those obtained by the conventional method. The second part focused on the interaction between different processes: Supercritical CO2, Enzymatic Assisted Extraction (EAE) and Microwave Assisted Extraction (MAE). The sequences of the processes allowed to propose a biorefinery perspective. The last part dealt with the optimization of fractionating method by Centrifugal Partition Chromatography (CPC). This innovative purification system led to isolate natural compounds such as Mycosporine-like Amino Acids with different properties, which can be valorized in the cosmetic field. This work enriches the knowledge of the seaweed S. chordalis and open a way of upgrading the proliferative biomass on the Brittany coasts

APA, Harvard, Vancouver, ISO und andere Zitierweisen

7

Lafontaine, Nadège. „Elaboration de systèmes de multiplication in vitro chez des algues marines“. Caen, 2011. http://www.theses.fr/2011CAEN2095.

Der volle Inhalt der Quelle

Annotation:

Chez les Rhodophytes et les Chlorophytes, certaines espèces sont des algues d’intérêt dermocosmétique. Elles sont actuellement récoltées ce qui entraîne des problèmes d’approvisionnement, d’hétérogénéité du matériel et de préservation des ressources naturelles. Pour produire toute l’année de la biomasse algale de qualité, différents systèmes de multiplication in vitro ont été évalués chez sept espèces. Pour quatre d’entre elles, des systèmes de micropropagation tenant compte de leurs particularités morphologiques, physiologiques et biochimiques et de leur comportement in vitro ont été mis au point. Une souche-mère in vitro à croissance lente chez une Chlorophyte a été mise en place par bouturage et les conditions physico-chimiques permettant à partir de la souche-mère d’établir des souches à croissance rapide ont été identifiées, seules ces dernières produisant des protoplastes. Chez une autre Chlorophyte, un système en boucle s’affranchissant complètement de la récolte a été réalisé à partir de prairies in vitro issues de protoplastes. La culture d’explants sur milieu solide chez deux Rhodophytes a mis en évidence leurs potentialités morphogénétiques dont la régénération de bourgeons. Chez une de ces deux Rhodophytes, la voie des protoplastes est également possible, la production de protoplastes a été optimisée mais seule la régénération sporadique de la paroi a été observée. Par contre, pour deux autres Rhodophytes, des protoplastes ont été obtenus suggérant la faisabilité de cette voie à condition de contourner l’intolérance à l’immersion pour l’une et de définir un protocole d’axénisation pour l’autre
Among Rhodophyta and Chlorophyta, some species have a dermocosmetic interest. For the time being seaweeds are harvested from wild populations leading to problems of supply, heterogeneous biomass and preservation of natural resources. In order to produce an algal biomass of quality throughout the year different systems of micropropagation were evaluated for seven species. For four of them systems of in vitro propagation based on their morphological, physiological and biochemical properties and their in vitro behavior were developed. A slow-growing stock culture of one Chlorophyta was initiated by cuttings and the physicochemical parameters were identified allowing to the establishment of fast-growing cultures. Protoplasts were produced only from these fast-growing cultures. A closed-loop system of micropropagation was elaborated from ‘in vitro seaweed beds’ of another Chlorophyta produced from protoplasts. Tissue culture on solid medium of two Rhodophyta showed their morphogenetic potentialities in particular the regeneration of shoots. The system of in vitro propagation from protoplasts is also possible for one of these Rhodophyta, the production of protoplasts was improved but only the sporadic regeneration of the cell wall was observed. Protoplasts were also obtained from two other Rhodophyta suggesting the feasibility of developing protoplast technology provided to bypass the intolerance of the immersion for the one and to elaborate the sterilization treatment for the other

APA, Harvard, Vancouver, ISO und andere Zitierweisen

8

Drouin, Annick. „Établissement et impacts de la macroalgue non indigène « Codium fragile ssp. fragile » dans les herbiers marins aux îles de la Madeleine“. Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/29902/29902.pdf.

Der volle Inhalt der Quelle

Annotation:

Les invasions biologiques sont reconnues comme une menace importante pour les écosystèmes, en particulier pour les écosystèmes côtiers. Originaire d’Asie, la macroalgue verte Codium fragile ssp. fragile (synonyme de ssp. tomentosoides, ci-après Codium) a été observée pour la première fois dans l’est du Canada en 1989 et prolifère depuis sur toutes les côtes du sud du golfe du Saint-Laurent. Cette algue est connue pour s’établir sur les côtes rocheuses, mais il a récemment été observé qu’elle est également capable de coloniser les habitats sableux et d’y former de denses populations en se fixant sur les rhizomes de la plante marine Zostera marina. L’objectif principal de cette thèse était de connaître les impacts de l’établissement de Codium dans les herbiers marins des îles de la Madeleine. L’étude du recrutement de Codium a démontré que l’expansion de la population de Codium était possible au sein des herbiers marins étudiés, mais que la colonisation était plutôt lente. De plus, il a été observé que le succès d’établissement de Codium dans les herbiers marins était variable spatialement. Là où Codium peut atteindre une grande biomasse, une expérience in situ a démontré que cela peut avoir un effet négatif sur la densité de zostère et les réserves d’hydrates de carbone dans les rhizomes. L’opacité du couvert algal serait le mécanisme expliquant ces observations en ayant pour effet de limiter la croissance clonale de la zostère, ainsi qu’influencer son allocation d’énergie. Ces effets n’étaient cependant pas perceptibles dans les herbiers naturellement envahis. Comme démontré par l’expérimentation, les effets sur la zostère ont lieu que lorsque Codium atteint une grande densité; or l'abondance de Codium varie annuellement et surtout les grandes biomasses sont peu fréquentes au sein des herbiers naturellement envahis. Il fut également démontré que les thalles de Codium offrent un habitat distinct des tiges de zostère pour l’épifaune, qui était plus abondante et diversifiée sur Codium. À plus grande échelle, la présence de Codium dans les herbiers influençait la distribution des poissons en favorisant la densité de certaines espèces. Finalement, aucun effet nuisible n’a été détecté sur la faune indigène.
Biological invasions are recognized as an important threat to ecosystems, in particular for coastal ecosystems. Native of Asia, the green seaweed Codium fragile ssp. fragile (synonymous of ssp. tomentosoides, herafter Codium) was first observed in eastern Canada in 1989 and has since been proliferous along the coasts of the southern Gulf of the St. Lawrence. This alga is known to establish on rocky shores, but it has recently been observed colonizing soft bottom habitat also, in particular forming dense canopies on eelgrass (Zostera marina) rhizomes. The main objective of this thesis was to identify the impacts of Codium establishment on eelgrass beds of the îles de la Madeleine. The study of Codium recruitment has shown that population expansion is possible within the studied eelgrass beds, but the colonization was rather low. Moreover, the success of Codium establishment in eelgrass beds varied spatially. Where Codium can reach a high biomass, An in situ experiment revealed that areas with high biomass of Codium can negatively effect eelgrass density and carbohydrate storage in rhizomes. A possible cause for these observations could be the shading created by algal cover, affecting clonal growth by eelgrass as well as influencing the plants allowance of energy. However, these effects were not detectable in naturally invaded beds. As shown, negative effects on eelgrass beds only occured when Codium biomass was high, an infrequent phenomenon that varied annually in the naturally invaded beds. It was also shown that thalli of Codium offer a distinctly different habitat than eelgrass shoots, resulting in more diverse and abundant epifauna on Codium. At a larger scale, the presence of Codium in eelgrass beds was found to influence fish distributions, by promoting higher density of certain species. However, no adverse effects were detected on native fauna.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

9

Salaün, Stéphanie. „Interactions entre la macroalgue brune Laminaria digitata et ses épibiontes bactériens : études moléculaire et spectroscopiques : capacité d’adhésion et de formation de biofilm“. Lorient, 2009. http://hal.upmc.fr/tel-01110841.

Der volle Inhalt der Quelle

Annotation:

Il est désormais admis que toute surface immergée en eau de mer est rapidement couverte d’un biofilm marin, suivi pour certaines de macrosalissures, essentiellement composées d’organismes marins vivants. Les thalles de macroalgues fournissent des surfaces importantes à la formation de biosalissures. Cependant, leur surface reste la plupart du temps exempt de macrosalissures, peut-être en relation avec leur succès évolutif, montrant leurs multiples stratégies de cohabitation avec leurs colonisateurs. Les macroalgues sont donc des modèles naturels de choix, susceptibles d’inspirer des solutions originales aux problèmes causés par les biofilms marins. Dans cette étude sur les bactéries associées aux thalles de l’algue brune Laminaria digitata, connue pour avoir un métabolisme halogéné particulier, nous avons isolé 18 souches bactériennes épiphytes, séquencé leur ADNr 16S et construit l’arbre phylogénétique correspondant. Puis nous les avons caractérisées par des méthodes spectroscopiques et étudié leur comportement d’adhésion et de formation de biofilm en présence de composés provenant de l’algue. Douze souches bactériennes marines de référence (Gram+ Firmicutes, et Gram– α-proteobacteria, γ-proteobacteria et Bacteroidetes) ont été traitées de la même manière. La taxonomie moléculaire des souches associées à L. Digitata a révélé des bactéries à Gram+ Actinobacteria et à Gram– α-proteobacteria, γ-proteobacteria et Bacteroidetes. Une base de données de profils spectraux des 30 souches a été construite en spectrométrie de masse MALDI-ToF à partir de cellules bactériennes entières. La signature spectrale propre à chaque souche bactérienne s’est révélée être un outil rapide et fiable à des fins taxonomiques. Les profils spectraux obtenus en RMN HR-MAS, également à partir de cellules entières, s’est avérée moins discriminante taxonomiquement que la MALDI-ToF. Cependant, les signatures spectrales variant en fonction du milieu de culture utilisé, la RMN HR-MAS s’est révélée être un outil utile dans l’étude des réponses d’adaptation physiologique bactérienne à l’environnement. Les souches bactériennes ont montré un pouvoir d’adhésion en microplaques en eau de mer filtrée stérile et de formation de biofilm en milieu ZoBell spécifique à la souche. Ces pouvoirs d’adhésion et de formation de biofilm pouvaient être plus ou moins sensible (augmenté ou diminué) lorsque des métabolites extraits et des exsudats de l’algue ont été co-incubés avec les souches. Les bactéries associées à L. Digitata ont été plus sensibles aux exsudats d’algue que les bactéries de référence, avec un effet majoritairement négatif sur l’adhésion et la formation de biofilm. Les métabolites extraits avec des solvants organiques, présents à la surface et dans l’algue, ont un effet majoritairement négatif sur l’adhésion de bactéries associées à l’algue, et positif sur l’adhésion des bactéries de référence. Enfin, des métabolites purs ont également été testés sur ces différentes souches, impliquant des réponses d’adhésion et de formation de biofilm propre à chaque souche
Once immersed in natural seawater, any surface will be rapidly colonized by biofilm forming bacteria, which tend to favour the establishment of sessile invertebrates, algae and protists as assemblages that cause macrofouling. Macrophytic algae represent very large surfaces for potential colonization by microbial and fouling epibionts. Yet actively growing parts are conspicuously devoid of visible epiphytism – presumably as a consequence of their evolutionary success based on a life long history of cohabitation with marine bacteria and other colonizers. As such, algae represent choice models upon which original antifouling biotechnologies may find inspiration. Our study is centered on the kelp Laminaria digitata which enjoys a unique metabolism featuring iodine and bromine processing haloperoxidases, and on its bacterial epiflora. We have isolated 18 cultivatable epiphytic strains of bacteria from selected surfaces of the thallus, we have sequenced their ADNr 16S, and we have built the corresponding phylogenetic tree from matches with online databases. Then, we characterized each strain from intact cell preparations by recording their proteome and their metabolome signature spectra, and finally we studied the adhesion and biofilm forming capabilities of selected strains when exposed to metabolites produced by their L. Digitata host. Twelve marine reference strains isolated from inert surfaces (Gram+ Firmicutes, and Gram– α-proteobacteria, γ-proteobacteria and Bacteroidetes) were treated accordingly as controls. Molecular taxonomy of bacterial strains associated with L. Digitata revealed Gram+ Actinobacteria and Gram– α-proteobacteria, γ-proteobacteria and Bacteroidetes. A spectral databank of 30 strains was built from MALDI-ToF mass spectra from entire cell preparations and the resulting individual signatures were found reliable and fast as taxonomic markers at the strain level. Spectral signatures obtained by proton HR-MAS NMR from intact cell preparations was less discriminative than MALDI-ToF in terms of attribution but quite informative as regards to variations in cultivation parameters and associated physiological responses on behalf of the bacteria. Adhesion and biofilm formation studies on selected strains showed that these processes are strain-specific under standard experimental conditions. Adhesion and biofilm could be modulated (up or down) by addition of exudates and metabolite extracts from L. Digitata that were solubilized in the medium of bacterial strains. Strains naturally associated with L. Digitata were more responsive to exposure to exudates than the environmental reference strains, the global effect being negative. Surface and tissue organic extracts had a globally negative effect on adhesion of bacteria naturally associated with L. Digitata, but showed a positive effect on the adhesion of reference bacteria. Finally, individual metabolites were tested with these bacterial strains, involving strain-specific responses of adhesion and biofilm formation

APA, Harvard, Vancouver, ISO und andere Zitierweisen

10

Monteiro, Lorena Soares. „AbsorÃÃo de nutrientes pela macroalga Gracilaria Birdiae (Plastino & Oliveira, 2002) sob diferentes condiÃÃes fÃsicoquÃmicas“. Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6700.

Der volle Inhalt der Quelle

Annotation:

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Dentre os recursos oriundos do mar, as macroalgas destacam-se como as de maior aproveitamento industrial. A sua abundÃncia e diversidade as tornam fontes de matÃria-prima para uma infinidade de produtos de uso humano e animal, alÃm dos benefÃcios ambientais resultantes da atividade algal na forma de O2 atmosfÃrico, remoÃÃo de nutrientes da Ãgua, modulaÃÃo climÃtica, combustÃveis fosseis e tambÃm na colheita de organismos que se alimentam das algas. A carcinicultura depende diretamente da boa qualidade da Ãgua para obter resultados satisfatÃrios de produÃÃo, portanto manter a qualidade do efluente da carcinicultura significa perpetuar a atividade. As macroalgas utilizam os nutrientes absorvidos para seu crescimento, enquanto contribuem com o melhoramento da qualidade ambiental dos ecossitemas aquÃticos. EspÃcies do gÃnero Gracilaria destacam-se pela capacidade de absorver rapidamente grandes quantidades de nutrientes dissolvidos orgÃnicos e inorgÃnicos. Neste trabalho objetivou-se avaliar a remoÃÃo de nutrientes da Ãgua de efluente de carcinicultura por macroalgas marinhas G. birdiae, a fim de fornecer informaÃÃes para um possÃvel cultivo integrado entre as espÃcies Litopenaeus vannamei e Gracilaria birdiae. Para isso, foram utilizados 25 recipientes onde foram distribuÃdos, aleatoriamente, 5 tratamentos com 5 repetiÃÃes, contendo 5, 10, 15 e 20 g de algas em 3 L de Ãgua de efluente de carcinicultura e ainda um controle sem algas. Este procedimento foi realizado com iluminaÃÃo constante e ainda com fotoperÃodo de 12h de claro e escuro, sendo tambÃm verificado a resistÃncia dos animais a situaÃÃo de dÃficit de oxigÃnio e o aporte de nutrientes para a Ãgua de cultivo dos animais. Cada experimento durou duas semanas e os resultados mostraram que a alga G. birdiae tem capacidade de retirar da Ãgua do efluente da carcinicultura em um curto perÃodo de tempo e em quantidades satisfatÃrias amÃnia e fÃsforo e ainda manter, sob iluminaÃÃo, concentraÃÃes suficientes de oxigÃnio na Ãgua.
Among marine resources, seaweeds have emerged as the one which have the largest industrial use. Their abundance and diversity make them a great source of raw material for countless products for human and animal use. More over seaweeds have a widely environmental importance, regarding to the atmospheric O2, water nutrients removing, fossil fuels, and also on the harvest of animals that eat marine algae. Shrimp culture is directly dependent on a good water quality for satisfactory production, therefore maintain the quality of shrimp farms effluent means to perpetuate the activity. Seaweeds absorb nutrients from the water and use them for their growth, while contribute to the environmental improvement of aquatic ecosystems. Gracilaria species stand out for the ability to quickly absorb large amounts of dissolved nutrients, not only organic, but also inorganic nutrients. This study aimed to evaluate the nutrients removal from the effluent water from a shrimp farm by the seaweed G. birdiae, in order to provide information for a possible integrated shrimp (Litopenaeus vannamei) and seaweed (G. birdiae) culture. For this, we used 25 containers, randomly distributed, with five treatments and five replications of 5, 10, 15 and 20 g of seaweed in 3 L of the effluent water from shrimp farm plus a control without seaweed. These procedures were performed with constant illumination and with a 12h light and dark photoperiod. The animals resistance of to periods of low oxygen, and the nutrients input generated by cultured animals have been checked. Each experiment lasted two weeks and the results showed that the alga G. birdiae has the capacity to withdraw from the shrimp farm effluent a satisfactory amount of ammonia and phosphorus in a short period of time, and still maintain, under illumination, sufficient concentrations of oxygen in the water. LISTA DE

APA, Harvard, Vancouver, ISO und andere Zitierweisen

11

Pye, Karen. „The effects of eutrophication on the marine benthic flora of Langstone Harbour, South Coast of England“. Thesis, University of Portsmouth, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343337.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

12

Brunet, Maéva. „Metabolic and ecological strategies of specialist bacteria mediating macroalgae breakdown“. Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS316.

Der volle Inhalt der Quelle

Annotation:

Les bactéries hétérotrophes sont des acteurs clés du recyclage de la biomasse algale. De nombreuses enzymes et voies cataboliques pour la dégradation de polysaccharides algaux purifiés ont été caractérisées. Cependant, ces mécanismes ne reflètent pas la complexité des réponses mises en œuvre pour dégrader des algues entières. J'ai donc étudié les stratégies écologiques et métaboliques de bactéries spécialistes de l'utilisation des macroalgues fraîches. La succession du microbiote épiphyte au cours de la décomposition de macroalgues a d’abord été étudiée. La présence du genre Zobellia, acteur clé de la dégradation, à la surface de diverses macroalgues a été montré. Son abondance varie selon les saisons et est particulièrement élevée dans le microbiote d’algues en décomposition. J'ai démontré que Zobellia galactanivorans DsijT utilise les algues brunes comme seule source de carbone, soulignant son rôle pionnier dans l’attaque de tissus algaux. Un ensemble de gènes, dont certains au sein de nouveaux loci dédiés à l’utilisation de polysaccharide (PUL) non caractérisés, étaient spécifiquement induits en présence d’algues. La caractérisation préliminaire de l’un de ces PUL a établi son rôle dans la dégradation de polysaccharides sulfatés contenant du fucose et conduit à la découverte de nouvelles activités enzymatiques chez Z. galactanivorans. Des interactions coopératives entre Z. galactanivorans et des Tenacibaculum spp. lors de l’utilisation de macroalgues ont été montrées. Par l’étude des mécanismes de dégradation de macroalgues à différentes échelles, cette thèse contribue à dévoiler les stratégies des bactéries marines hétérotrophes dans le devenir de la biomasse algale
Heterotrophic bacteria are key players in algal biomass recycling. Numerous works focused on the degradation of purified algal polysaccharides and discovered new enzymes and catabolic pathways. However, this strategy does not reflect the structural complexity of the algal extracellular matrix. In this thesis I implemented diverse approaches to decipher the ecological and metabolic strategies of bacteria specialized in the utilization of fresh macroalgae. I evidenced a succession of the epiphytic microbiota during in situ macroalgae decomposition. The presence of the known algal-polysaccharides degrader genus Zobellia was assessed on diverse macroalgae. Its abundance was season-dependent and particularly high on decaying algae. I demonstrated that Zobellia galactanivorans DsijT has the capacity to use fresh brown algae as a sole carbon source, highlighting a specific pioneer degrader behaviour. The analysis of its transcriptome revealed the induction of a subset of genes, including novel uncharacterized polysaccharide utilization loci (PULs), specifically induced with intact algae. The preliminary characterization of one of these PULs demonstrated its role in the degradation of fucose-containing sulfated polysaccharides and led to the discovery of novel enzymatic activities in Z. galactanivorans. Co-culture experiments showed that Z. galactanivorans supported the growth of Tenacibaculum spp. with macroalgae, bringing out cooperative interactions between pioneer and opportunist bacteria. By studying macroalgae degradation mechanisms at different scales, this thesis contributes to unveil the strategies of heterotrophic marine bacteria in the fate of macroalgal biomass

APA, Harvard, Vancouver, ISO und andere Zitierweisen

13

BOISSON, FLORENCE. „Teneur en selenium du microplancton de la mer ligure (mediterranee nord-occidentale). Toxicite et bioaccumulation du selenium chez une microalgue cricosphaera elongata et une macroalgue bryopsis maxima“. Paris 6, 1992. http://www.theses.fr/1992PA066418.

Der volle Inhalt der Quelle

Annotation:

La teneur mediane en selenium du microplancton de la mer ligure (mediterranee nord-occidentale) est de 0,62 microgrammes par gramme de poids sec (0,57 pour le microzooplancton et de 0,20 a 0,90 pour le microphytoplancton). Les fluctuations sont importantes lors du brassage vertical hivernal des masses d'eau ou faibles du fait de la composition specifique de la peche. La teneur en selenium du microplancton est une fonction lineaire inverse de la biomasse microzooplanctonique, mais lors d'une floraison phytoplanctonique elle augmente avec la biomasse de diatomees. Seul le selenite (se iv) stimule la croissance et le metabolisme des deux algues et protege de la peroxydation les lipides membranaires de la microalgue cricosphaera elongata. Les effets toxiques apparaissent au-dela de la concentration en selenium mesuree en milieu pollue: ralentissement de la multiplication cellulaire de c. Elongata et degradation de la chlorophylle a avec synthese d'un pigment orange pour la macroalgue bryopsis maxima. Le selenium penetre a travers les membranes, de facon controlee chez c. Elongata ou simple chez b. Maxima. La teneur intracellulaire en selenium reste stationnaire grace au pompage vers l'exterieur; pour la premiere algue: le niveau est bas pour le seleniate et plus eleve pour le selenite dont 41% est libre dans le cytosol et 58% est associe aux proteines; pour la seconde algue: le niveau intracellulaire n'est pas modifie par 8 jours de decontamination

APA, Harvard, Vancouver, ISO und andere Zitierweisen

14

Le, Guillard Cécile. „Application de l’hydrolyse enzymatique assistée par ultrasons à la macroalgue rouge Grateloupia turuturu : Étude de la liquéfaction de la biomasse et de l’extraction de la R-phycoérythrine“. Nantes, 2016. https://archive.bu.univ-nantes.fr/pollux/show/show?id=25972c5c-a45e-4003-b24b-c9235ec39834.

Der volle Inhalt der Quelle

Annotation:

Les macroalgues rouges possèdent un large panel de molécules d’intérêt pour différents domaines d’applications. Cette étude porte sur une espèce non-indigène des côtes françaises, Grateloupia turuturu, en vue d’intensifier sa liquéfaction pour l’extraction de ses composés et en particulier celle d’un pigment d’intérêt, la R-phycoérythrine (R-PE). Trois procédés d’extraction ont été étudiés : l’extraction assistée par hydrolyse enzymatique (EAE), par ultrasons (UAE) et par ultrasons et hydrolyse enzymatique (UAEH). Pour ce faire, quatre complexes enzymatiques de polysaccharidases industrielles et un générateur d'ultrasons tubulaire ont été utilisés. Dans un premier temps, l’efficacité de ces trois procédés, à 40 °C, a été évaluée par la liquéfaction de l’algue. Cette étude a montré que le couplage (UAEH) permet la liquéfaction la plus importante de l’algue, avec plus de 90 % de matière solubilisée. Il a ensuite été décidé de poursuivre cette étude avec l’UAE et l’UAEH. La comparaison de ces deux procédés, à 22 et 40 °C, a montré que l’UAEH était le procédé le plus efficace pour l’extraction de la R-PE et la liquéfaction de l’algue. Il a également été démontré que l’UAEH à 22 °C était préférable pour la R-PE tandis qu’une température de 40 °C favorisait la liquéfaction de G. Turuturu. La relative stabilité de la R-PE aux ultrasons a également été démontrée. Pour finir, l’étude de différents paramètres de l’UAEH (débit, température et puissance) a permis d’optimiser la liquéfaction de G. Turuturu et l’extraction de la R-PE. Les résultats de ce travail de thèse démontrent l’intérêt du couplage ultrasons-enzymes dans l’extraction des composés de G. Turuturu
Red seaweeds contain a large range of molecules of interest for different applications. This study concerns a non-native species of the French coast, Grateloupia turuturu, with a view to intensify its liquefaction for the extraction of its compounds, more particularly a pigment of interest, the R-phycoerythrin (R-PE). Three extraction methods were studied: enzymatic assisted extraction (EAE), ultrasound-assisted extraction (UAE) and ultrasoundassisted enzymatic hydrolysis (UAEH). Four industrial enzymatic preparations of carbohydrases and an ultrasonic flow-through reactor were used. First, the three processes efficiency, at 40 °C, was estimated by the liquefaction of seaweeds. This study demonstrated that the combination (UAEH) allows to obtain the highest liquefaction rate of seaweed, with more than 90 % of solubilized material. It was then decided to continue this study with the UAE and the UAEH. A comparison between the two processes, at 22 and 40 °C, demonstrated that the UAEH was the most efficient for the R-PE extraction and the liquefaction of seaweed. It was also demonstrated that the UAEH at 22 °C was preferable for the R-PE, whereas for the liquefaction of G. Turuturu the best temperature was 40 °C. The relative stability of R-PE towards the ultrasound was also demonstrated. To finish, the study of different UAEH parameters (flow, temperature and power) has allowed to optimize the liquefaction of G. Turuturu and the extraction of R-PE. These thesis results demonstrate the interests of this combination ultrasound-enzymes for the extraction of G. Turuturu compounds

APA, Harvard, Vancouver, ISO und andere Zitierweisen

15

FONTES, Khey Albert de Azevedo. „Taxonomia e distribuição geográfica do gênero Bostrychia Montagne (Ceramiales-Rhodophyta) nos manguezais do litoral brasileiro“. Universidade Federal Rural de Pernambuco, 2012. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/4843.

Der volle Inhalt der Quelle

Annotation:

Submitted by (edna.saturno@ufrpe.br) on 2016-06-22T13:34:25Z No. of bitstreams: 1 Khey Albert de Azevedo Fontes.pdf: 1733610 bytes, checksum: d510ff54a848b88ff568ecb7f9dd7a64 (MD5)
Made available in DSpace on 2016-06-22T13:34:25Z (GMT). No. of bitstreams: 1 Khey Albert de Azevedo Fontes.pdf: 1733610 bytes, checksum: d510ff54a848b88ff568ecb7f9dd7a64 (MD5) Previous issue date: 2012-06-22
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The taxonomic studies based on morphological characters do not have effective success in the separation of lineages of the genus Bostrychia, an important component of the association of epiphytic macroalgae of mangrove denominated as "Bostrychietum." The data obtained by methods in molecular biology have proved more efficient in grouping with regular relationship. Thus, the data often go beyond the traditional classification of this genus, featuring a high occurrence of reproductively incompatible haplotype although relatively close source. Considering the high morphological plasticity of their representatives in infrageneric level, this work aimed to present the taxonomy and distribution of species of Bostrychia from mangroves occurring in the Brazilian coast. The morphological and anatomical studies were based on material collected in different Brazilian coastal mangroves, and exsicates deposited in indexed national herbaria. Macroalgae samples were collected with spatule. For taxonomic survey, it was fixed in phormaldehyde solution (4%), packed in falcon tubes (50 ml). For molecular survey, it was fixed in Ethanol P. A. and small pieces of the youngest parts of the plants has been extracted. It has been packed in silica gel. The identification of taxa followed the traditional taxonomic criteria through consultation with relevant bibliography. Allied to the taxonomic studies were used as auxiliary markers in order to better understand the polymorphism found in species of Bostrychia. We identified six species of Bostrychia in mangroves of the Brazilian coast: Bostrychia calliptera (Mont.) Mont., Bostrychia montagnei Harv., Bostrychia moritziana (Sond. ex Kutz.) J. Agardh, Bostrychia pilulifera Mont., Bostrychia radicans (Mont.) Mont. in Orb. and Bostrychia tenella (J. V.Lamour.) J. Agardh. The genus Bostrychia Mont. showed a wide distribution in the mangrove areas of the Brazilian coast. Two different lineages of B. radicans were observed using molecular markers. Molecular data suggest that B. binderi Harv. should be considered as a taxonomic entity from B. tenella (J. V. Lamour.) J.Agardh.
Os estudos taxonômicos baseados apenas em caracteres morfológicos não apresentam total eficácia na separação de linhagens das espécies do gênero Bostrychia Mont., um componente importante da associação de macroalgas epífitas de manguezal de nominada de “Bostrychietum”. Os dados obtidos através de métodos em biologia molecular têm se mostrado cada vez mais eficientes na determinação de grupos com regular parentesco. Desta forma, os dados frequentemente extrapolam a classificação tradicional deste gênero, caracterizando uma grande ocorrência de haplótipos reprodutivamente incompatíveis muito embora de origem relativamente próxima. Considerando a elevada plasticidade morfológica de seus representantes em nível infragenérico, a presente pesquisa teve como objetivo apresentar a taxonomia e a distribuição geográfica das espécies do gênero Bostrychia ocorrentes nos manguezais do litoral brasileiro. Os estudos morfoanatômicos foram baseados em material coletado em diversos manguezais do litoral brasileiro, além de material depositado em herbários nacionais indexados. As amostras foram coletadas com o auxílio de espátula. Para a abordagem taxonômica, foram fixadas em solução de formol (4%), neutralizadas com bórax (1%) e devidamente acondicionadas em tubos de falcon (50ml). Para a abordagem molecular, foram imediatamente acondicionadas em tubos de falcon (50ml) contendo etanol P. A., foram retiradas pequenas amostras das partes mais jovens dos espécimes e acondicionadas em sílica gel. A identificação dos táxons seguiu os critérios taxonômicos tradicionais através de consulta a bibliografia pertinente. Aliado aos estudos taxonômicos foram utilizados como ferramenta auxiliar marcadores moleculares (UPA, cox1 e rbcL) visando entender melhor o polimorfismo encontrado nas espécies de Bostrychia. Foram identificadas seis espécies de Bostrychia nos manguezais da costa brasileira: Bostrychia calliptera (Mont.) Mont., Bostrychia montagnei Harv., Bostrychia moritziana (Sond. ex Kutz.) J. Agardh, Bostrychia pilulifera Mont., Bostrychia radicans (Mont.) Mont. in Orb. e Bostrychia tenella (J. V. Lamour.) J. Agardh. O gênero Bostrychia apresentou uma larga distribuição nas áreas de manguezal da costa brasileira. Duas linhagens diferentes de B. radicans foram observadas usando os marcadores moleculares. Dados moleculares sugerem que B. binderi Harv. deve ser considerada como uma entidade taxonomica diferente de B. tenella (J. V. Lamour.) J. Agardh.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

16

Margarido, Tatiana Cristina Stefani. „Biomarcadores de exposição em macroalgas Gracilaria domingensis expostas a cádmio e cobre“. Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/9/9141/tde-02032017-123729/.

Der volle Inhalt der Quelle

Annotation:

Nos últimos anos, os metais vêm ganhando maior atenção em estudos devido aos impactos causados no ambiente, sua persistência e capacidade de bioacumulação e biomagnificação. As zonas costeiras por sua localização sofrem danos maiores, principalmente devido à grande quantidade de efluentes depositada nessa área provenientes de atividades urbanas, industriais, agrícolas e mineiras, dentre outras. As algas são organismos que compõe a base da cadeia alimentar e possuem ainda capacidade de estocar metais tornando-os menos disponíveis para as espécies que habitam a região. Tal característica torna esse organismo uma alternativa economicamente viável e ecológica em processos de biorremediação. As macroalgas pertencentes ao gênero Gracilaria, possuem grande importância econômica na produção de ágar, e alguns de seus metabólitos são utilizados no ramo farmacêutico, medicinal e de cosméticos. No entanto, esse gênero pode ser também um bom bioindicador da presença de metais, e os efeitos causados por esses compostos, potenciais biomarcadores. O objetivo presente estudo é verificar os efeitos dos metais cobre (Cu) e cádmio (Cd) em enzimas antioxidantes e de biotransformação na espécie Gracilaria domingensis, e os mecanismos de retenção e detoxificação desses metais. A descrição desses mecanismos visa contribuir com a possibilidade de utilização dessas macroalgas para remediação de ambientes impactados. Para tanto foram desenvolvidos experimentos para definição de valores de IC50 que estabeleceram que os valores de IC50 para o cobre e cádmio para espécie Graciliaria domingensis são 10,6 e 1,05 mg/L, respectivamente. E foram feitos experimentos utilizando as concentrações de cobre de 5,3 e 10,6 mg/L (½ IC50 e IC50) por períodos de 1, 24 e 48 horas. Experimentos com grupos de recuperação, além de experimentos utilizando as concentrações determinadas pelo CONAMA 357/2005 e experimentos de perfil temporal de formação de fitoquelatinas e resposta de biomarcadores após 24, 48, 72 e 96 horas de exposição. As análises das algas expostas demonstraram aumento na atividade da glutationa peroxidase (GPx), glutationa-Stransferase (GST) e ascorbato peroxidase (APx). No entanto, a catalase (CAT) não apresentou atividade detectável, nem mesmo na presença do metal. As análises teste de fitoquelatinas, GSH e GSSG foram inconclusivas, porém os novos testes realizados com concentrações legisladas e relativas ao IC50 mostraram alterações significativas nos níveis de GSSG e GSH para exposição ao cobre, no entanto, o grupo tratado com cádmio foi o único que apresentou fitoquelatinas detectáveis. A espécie Gracilaria domingensis tem demonstrado potencial como organismos bioindicador e os biomarcadores estão fornecendo resultados promissores.
In the last years great importance are being dedicated to the research of metals because of their environmental impact, persistence and the possibility of bioacummulation and biomagnification. The large amount of effluents produced by urban, industrial, agricultural and mining activities among others affect particularly the coastal areas. In this context, the algae which compose the basis of the foodweb, and have the capacity to stock metals decreasing their availability in the environment and therefore to other species inhabiting the area. Such characteristic make the algae a feasibly economic and ecological alternative to be used in bioremediation approaches. Macroalgae belonging to the genus Gracilaria, possess already an economical importance in the production of agar and, some of its metabolites are commonly used in the pharmaceutical industry. The organisms of this genus can also be an indicator of the metal presence in the environment and the effects caused by these compounds potential biomarkers. The objective of this project is to assess the effect of copper (Cu) and cadmium (Cd) on antioxidant or biotransformation enzymes in the algae Gracilaria domingensis and also the mechanisms of retention and detoxification of these metals. The description of these mechanisms can contribute to further use this macroalgae to bioremediation processes. Experiments established the IC50 of copper and cadmium in Gracilaria domingensis at 10.6 and 1.05 mg. L-1, respectively. Experiments using the copper\'s concentrations 5.3 and 10.6 mg. L-1 (½ IC50 and IC50) for 1, 24 and 48 h of were performed. Besides experiments with recovery groups, experiments using CONAMA 357/2005 concentration and experiment with different times of exposure (24, 48,72 and 96 hours) to understand better when phytochelatins starts to be produced and a profile of biomarkers The analysis of exposed algae to copper demonstrated an increased activity of glutathione peroxidase (GPx), glutathione-S-transferase (GST) and ascorbate peroxidase (APx). Interestingly, the catalase (CAT) activity was not detected even though in the presence of metal. Other experiments using concentration determined by CONAMA and IC50 was performed, as well experiments using recovery groups, and a temporal profile, to see the results for 24, 48, 72 e 96 hours of exposure. The analysis of phytochelatine, GSH and GSSG test were inconclusive and new conducted tests with CONAMA\'s and IC50 concentration showed significant alterations in the levels of GSSG e GSH for the samples exposed to copper, however, only the group treated with cadmium demonstrated detectable levels of phytochelatin. The species Gracilaria domingensis has been demonstrating the potential as a bioindicator organism and the biomarkers are producing promising results.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

17

Cruz, Ana Raquel Lima da. „A importância das macroalgas castanhas para o desenvolvimento de nutracêuticos“. Bachelor's thesis, [s.n.], 2018. http://hdl.handle.net/10284/7370.

Der volle Inhalt der Quelle

Annotation:

Trabalho Complementar apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de licenciada em Ciências da Nutrição
A crescente preocupação da população em geral com a saúde e bem-estar incentiva a indústria a apostar em produtos que se revelam benéficos na prevenção e/ou tratamento de doenças. A natureza tem sido desde sempre a maior fonte de moléculas com atividades biológicas interessantes. Nos últimos anos tem vindo a crescer o interesse pelo estudo dos compostos obtidos de organismos marinhos, nomeadamente as macroalgas. As macroalgas são um grupo muito heterogéneo que pode ser subdivido em três grupos distintos de acordo com a pigmentação que apresentam. As macroalgas castanhas por possuírem compostos exclusivos são estudadas intensivamente. Com um elevado valor nutritivo, mas de um baixo teor calórico, as macroalgas castanhas apresentam na sua constituição, entre outros compostos, metabolitos secundários biologicamente ativos nomeadamente polifenóis, que além de conferirem proteção às macroalgas ainda apresentam, entre outras, propriedades antioxidantes e anti-inflamatórias que podem ser incorporados em nutracêuticos. Com o desenvolvimento deste trabalho, pretende-se analisar as propriedades biológicas de diversos compostos extraídos das macroalgas castanhas e os seus possíveis benefícios na incorporação dos mesmos em nutracêuticos.
The greater concern of the general population with health and well-being encourages an industry in products that show benefits in the prevention and / or treatment of diseases. Nature has always been the largest source of molecules with interesting biological activities. In recent years there has been growing interest in the study of compounds of marine organisms, such as macroalgae. Macroalgae are a very heterogeneous group that can be subdivided into three distinct groups according to a pigmentation it presents. As brown macroalgae because they have a way of getting free are intensively studied. With a high nutritional value, but with low caloric content, such as brown macroalgae, among others, metabolites that are biologically active are polyphenols, which also confer the guarantee to macroalgae still present, among others, antioxidant and anti-oxidant properties that can be incorporated into nutraceuticals. In order to carry out the work, we intend to analyze the biological characteristics of the compounds extracted from the macroalgae and to allow the incorporation of the same in nutraceuticals.
N/A

APA, Harvard, Vancouver, ISO und andere Zitierweisen

18

Monteiro, Lorena Soares. „Absorção de nutrientes pela macroalga Gracilaria Birdiae (Plastino & Oliveira, 2002) sob diferentes condições físicoquímicas“. reponame:Repositório Institucional da UFC, 2011. http://www.repositorio.ufc.br/handle/riufc/18476.

Der volle Inhalt der Quelle

Annotation:

MONTEIRO, Lorena Soares. Absorção de nutrientes pela macroalga Gracilaria Birdiae (Plastino & Oliveira, 2002) sob diferentes condições físicoquímicas. 2011. 84 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2011
Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-19T12:37:53Z No. of bitstreams: 1 2011_dis_lsmonteiro.pdf: 9821963 bytes, checksum: fad7e704cc8bfb703229d456567e5115 (MD5)
Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-19T13:28:20Z (GMT) No. of bitstreams: 1 2011_dis_lsmonteiro.pdf: 9821963 bytes, checksum: fad7e704cc8bfb703229d456567e5115 (MD5)
Made available in DSpace on 2016-07-19T13:28:20Z (GMT). No. of bitstreams: 1 2011_dis_lsmonteiro.pdf: 9821963 bytes, checksum: fad7e704cc8bfb703229d456567e5115 (MD5) Previous issue date: 2011
Among marine resources, seaweeds have emerged as the one which have the largest industrial use. Their abundance and diversity make them a great source of raw material for countless products for human and animal use. More over seaweeds have a widely environmental importance, regarding to the atmospheric O2, water nutrients removing, fossil fuels, and also on the harvest of animals that eat marine algae. Shrimp culture is directly dependent on a good water quality for satisfactory production, therefore maintain the quality of shrimp farms effluent means to perpetuate the activity. Seaweeds absorb nutrients from the water and use them for their growth, while contribute to the environmental improvement of aquatic ecosystems. Gracilaria species stand out for the ability to quickly absorb large amounts of dissolved nutrients, not only organic, but also inorganic nutrients. This study aimed to evaluate the nutrients removal from the effluent water from a shrimp farm by the seaweed G. birdiae, in order to provide information for a possible integrated shrimp (Litopenaeus vannamei) and seaweed (G. birdiae) culture. For this, we used 25 containers, randomly distributed, with five treatments and five replications of 5, 10, 15 and 20 g of seaweed in 3 L of the effluent water from shrimp farm plus a control without seaweed. These procedures were performed with constant illumination and with a 12h light and dark photoperiod. The animals resistance of to periods of low oxygen, and the nutrients input generated by cultured animals have been checked. Each experiment lasted two weeks and the results showed that the alga G. birdiae has the capacity to withdraw from the shrimp farm effluent a satisfactory amount of ammonia and phosphorus in a short period of time, and still maintain, under illumination, sufficient concentrations of oxygen in the water. LISTA DE
Dentre os recursos oriundos do mar, as macroalgas destacam-se como as de maior aproveitamento industrial. A sua abundância e diversidade as tornam fontes de matéria-prima para uma infinidade de produtos de uso humano e animal, além dos benefícios ambientais resultantes da atividade algal na forma de O2 atmosférico, remoção de nutrientes da água, modulação climática, combustíveis fosseis e também na colheita de organismos que se alimentam das algas. A carcinicultura depende diretamente da boa qualidade da água para obter resultados satisfatórios de produção, portanto manter a qualidade do efluente da carcinicultura significa perpetuar a atividade. As macroalgas utilizam os nutrientes absorvidos para seu crescimento, enquanto contribuem com o melhoramento da qualidade ambiental dos ecossitemas aquáticos. Espécies do gênero Gracilaria destacam-se pela capacidade de absorver rapidamente grandes quantidades de nutrientes dissolvidos orgânicos e inorgânicos. Neste trabalho objetivou-se avaliar a remoção de nutrientes da água de efluente de carcinicultura por macroalgas marinhas G. birdiae, a fim de fornecer informações para um possível cultivo integrado entre as espécies Litopenaeus vannamei e Gracilaria birdiae. Para isso, foram utilizados 25 recipientes onde foram distribuídos, aleatoriamente, 5 tratamentos com 5 repetições, contendo 5, 10, 15 e 20 g de algas em 3 L de água de efluente de carcinicultura e ainda um controle sem algas. Este procedimento foi realizado com iluminação constante e ainda com fotoperíodo de 12h de claro e escuro, sendo também verificado a resistência dos animais a situação de déficit de oxigênio e o aporte de nutrientes para a água de cultivo dos animais. Cada experimento durou duas semanas e os resultados mostraram que a alga G. birdiae tem capacidade de retirar da água do efluente da carcinicultura em um curto período de tempo e em quantidades satisfatórias amônia e fósforo e ainda manter, sob iluminação, concentrações suficientes de oxigênio na água.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

19

Pires, Kelma Maria dos Santos. „AvaliaÃÃo sazonal de carotenÃides provitamina A (αâ e βâ caroteno) e vitamina E (αâtocoferol) em macroalgas marinhas pertencentes a famÃlia Caulerpacea (DivisÃo Chlorophyta)“. Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6898.

Der volle Inhalt der Quelle

Annotation:

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
As algas marinhas sÃo fontes de uma grande variedade de compostos benÃficos para o homem, dentre os quais se destacam os minerais, as fibras dietÃrias e as vitaminas (A, B, C e E). O objetivo deste trabalho foi verificar a existÃncia de variaÃÃo sazonal nos teores de α- e β-caroteno (carotenÃides provitamina A) e de α-tocoferol (vitamina E), em cinco espÃcies de macroalgas marinhas pertencentes ao gÃnero Caulerpa (FamÃlia Caulerpaceae, DivisÃo Chlorophyta), âin naturaâ e desidratada. Os conteÃdos desses nutrientes nas algas desidratadas foram comparados com aqueles nas algas âin naturaâ, com o objetivo de verificar se houve alteraÃÃo pelo processo de desidrataÃÃo. As espÃcies de macroalgas marinhas foram coletadas mensalmente, de janeiro a dezembro de 2006, durante as marÃs baixas na Praia do Pacheco, Caucaia- CE. As anÃlises de α- e β-caroteno e α-tocoferol foram realizadas a partir da extraÃÃo da alga em metanol-Ãgua (90:10) nas proporÃÃes 1:10 (p/v), nas amostras âin naturaâ, e 1:20 (p/v), nas desidratadas, saponificaÃÃo com hidrÃxido de potÃssio 5% por 30 min a 70ÂC e partiÃÃo em n-hexano que foi evaporado sob corrente de ar. O resÃduo foi suspenso em 1 mL de metanol no momento da anÃlise cromatogrÃfica e 100 μL foram injetados manualmente. O sistema cromatogrÃfico consistiu em uma coluna Waters Spherisorb-Hichrom S5ODS-2 (4,6 x 250 mm) e uma fase mÃvel constituÃda de metanol:tetrahidrofurano (90:10, v/v), com fluxo de 1,5 mL min-1. O detector foi ajustado em 450 nm e 292 nm e os cromatogramas registrados atravÃs do sistema UnicornTM versÃo 5.0. Todas as espÃcies de Caulerpa âin naturaâ e desidratadas analisadas no presente trabalho apresentaram tanto α-caroteno quanto β-caroteno e as suas distribuiÃÃes mostraram diferenÃas ao longo dos doze meses de coleta. De um modo geral, os teores de α-caroteno foram superiores aos de β-caroteno. As perdas nos conteÃdos de carotenÃides provitamina oscilaram entre 10% e 94%. Para que as algas analisadas neste trabalho fossem consideradas fontes excelentes de vitamina A seria necessÃrio que as porÃÃes consumidas diariamente variassem de 52 g a 689 g, quando consumidas âin naturaâ ou de 42 g a 469 g, quando desidratadas. As cinco espÃcies analisadas neste trabalho apresentaram α-tocoferol, tanto nas amostras âin naturaâ quanto nas desidratadas, com exceÃÃo de C. racemosa coletada em marÃo que apÃs ser submetida a secagem nÃo foi detectado α- tocoferol, e sua distribuiÃÃo foi variÃvel ao longo do ano. Nos teores de α- tocoferol foi observado perdas que variaram de 22 a 91%. As porÃÃes que deveriam ser consumidas diariamente para que as espÃcies de Caulerpa estudadas fossem capazes de fornecer 1/2 da IDR sÃo relativamente pequenas, devendo oscilar entre 11 g e 168 g, quando âin naturaâ, ou entre 13 g e 70 g, quando desidratadas. As quantidades de retinol equivalente e α-tocoferol equivalente nas algas analisadas no presente trabalho nÃo diferiram muito daquelas encontradas nos vegetais normalmente consumidos
Marine macroalgae are sources of a great variety of beneficial compounds such as minerals, dietary fibers and vitamins. The aim of this work was to verify seasonal variation upon both provitamin A carotenoids (α- and β-carotene) and vitamin E (α-tocopherol) contents in five species of the marine green macroalga Caulerpa both fresh and oven-dried at 40ÂC for 15 h. The contents in dried algae were compared to those in fresh algae to evaluate the losses after drying. Algal material was collected monthly from January to December 2006, in Pacheco Beach, Caucaia, CearÃ. Analyses of α- and β-carotene and α-tocopherol were carried out in extracts 1:10 (p/v) for fresh alga and 1:20 (p/v) for dried alga using aqueous methanol (90:10, v/v). They were saponified with 5% KOH and partitioned into n-hexane, which was then evaporated. The residues were suspended in 1 mL methanol prior to HPLC analyses. Aliquots of 100 μL were injected in a HPLC system consisting of a Waters Spherisorb-Hichrom S5 ODS-2 column (4.6 x 250 mm) and a mobile phase of methanol:tetrahydrofurane (90:10, v/v), delivered at 1.5 mL min-1. The detector was set at 450 nm for α- and β-carotene and 290 nm for α-tocopherol. Chromatograms were registered at UnicornTM version 5.0. All samples showed α- and β-carotene and α-tocopherol, but their distribution along the year was variable. In general, the contents of α-carotene were greater than those of β-carotene. The losses of α- and β-carotene varied between 10% and 94%. In order to be considered an excellent source of vitamin A, the daily consumption would be 52 g to 689 g of fresh alga or 42 g to 469 g of dried alga. α-Tocopherol was detected in all samples except in dried C. racemosa collected in March. Similar to the distribution of α- and β-carotene along the year, α-tocopherol contents varied too. Losses varied from 22% to 91%. Daily portions to supply 50% of the Recommended Daily Allowance (RDA) would be 11 g to 168 g of fresh alga or 13 g to 70 g of dried alga. Amounts of vitamin A (retinol equivalents) and vitamin E (tocopherol equivalents) in all algae analyzed were not very different from most vegetables normally consumed

APA, Harvard, Vancouver, ISO und andere Zitierweisen

20

Sousa, MÃrcia Barbosa de. „ExtraÃÃo e quantificaÃÃo de α-Caroteno, β-Caroteno e α-Tocoferol em macroalgas marinhas utilizando cromatografia lÃquida de alta eficiÃncia em fase reversa“. Universidade Federal do CearÃ, 2005. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8021.

Der volle Inhalt der Quelle

Annotation:

O objetivo deste trabalho foi avaliar o potencial de 32 espÃcies de algas marinhas das divisÃes Chlorophyta, Rhodophyta e Phaeophyta como fontes de α-, β-caroteno e α-tocoferol. Todas as Chlorophyta apresentaram α- e β-caroteno. O teor de α-caroteno variou de 0,814 Â 0,256 a 71,378 Â 3,550 μg.g -1 peso fresco, sendo mais elevado no gÃnero Caulerpa e mais baixo em Codium decorticatum. O teor de β-caroteno variou de 2,322 Â 0,736 a 26,705 Â 7,398 μg.g -1 peso fresco, sendo mÃnimo em C. mexicana e mÃximo em Ulva fasciata. Com relaÃÃo ao retinol equivalente (RE), as algas verdes apresentaram mÃnimo em C. mexicana (0,962 Â 0,256 μg.g -1 ) e mÃximo em Caulerpa prolifera (9,014 Â 0,442 μg.g -1 ). Considerando a ingestÃo de 100 g de alga fresca por dia, uma porÃÃo de Caulerpa prolifera forneceria 100% da ingestÃo diÃria recomendada (IDR). Todas as Chlorophyta apresentaram α-tocoferol, exceto Cladophora prolifera. Os teores mÃnimo e mÃximo foram 15,650 Â 2,634 e 383,047 Â 85,254 μg.g -1 peso fresco em Codium decorticatum e Caulerpa prolifera, respectivamente. Com relaÃÃo ao tocoferol equivalente (TE), a ingestÃo diÃria de 100 g de Caulerpa prolifera fresca forneceria quase quatro vezes mais que a IDR e a mesma porÃÃo de Codium decorticatum seria responsÃvel por apenas 1 /6 da IDR. Dentre as Rhodophyta estudadas, nove nÃo apresentaram α-caroteno. Nas outras onze, o seu teor oscilou de 0,487 Â 0,267 μg.g -1 em Solieria filiformis a 3,055 Â 0,278 μg.g -1 peso fresco em Botryocladia occidentalis. β-Caroteno foi encontrado em todas as espÃcies de algas vermelhas com valores mÃnimo e mÃximo de 0,336 Â 0,209 e 4,284 Â 0,607 μg.g -1 de peso fresco em Gracilaria caudata e Bryothamnion triquetrum, respectivamente. Com relaÃÃo ao RE, foi observado valor mÃnimo em Gracilaria caudata (0,056 Â 0,035 μg.g -1 ) e mÃximo em Bryothamnion triquetrum (0,764 Â 0,109 μg.g -1 ). Uma porÃÃo de 100 g de Bryothamnion triquetrum fresca forneceria um pouco mais de 1 /10 da IDR. Oito espÃcies de Rhodophyta estudadas nÃo apresentaram α-tocoferol. Nas outras doze, seu conteÃdo oscilou entre 4,809 Â 1,058 e 31,872 Â 5,883 μg.g -1 peso fresco, em Gracilaria ferox e Enantiocladia duperreyi, respectivamente. Em relaÃÃo ao TE, a ingestÃo diÃria de 100 g da alga E. duperreyi fresca forneceria 1 /3 da IDR. As Phaeophyta estudadas apresentaram apenas β-caroteno, com valores mÃnimo e mÃximo em Dictyopteris delicatula e Padina gymnospora, iguais a 0,266 Â 0,198 e 12,230 Â 2,859 μg.g -1 peso fresco, respectivamente. Com relaÃÃo ao RE, o teor mÃnimo foi observado em Dictyopteris delicatula (0,044 Â 0,033 μg.g -1 ) e mÃximo em Padina gymnospora (2,038 Â 0,476 μg.g -1 ). Considerando a ingestÃo diÃria de 100 g de alga fresca, uma porÃÃo de P. gymnospora seria responsÃvel por 1 /4 da IDR. As Phaeophyta apresentaram α-tocoferol, com valor mÃnimo em Lobophora variegata igual a 4,722 Â 2,062 μg.g -1 peso fresco e mÃximo em Dictyota dichotoma, igual a 42,817 Â 31,012 μg.g -1 peso fresco. Considerando a ingestÃo de 100 g de alga fresca por dia, uma porÃÃo de Dictyota dichotoma forneceria 1 /2 da IDR de TE
The aim of this work was to evaluate the potential of 32 marine macroalga species belonging to Chlorophyta, Rhodophyta and Phaeophyta as sources of α-carotene, β-carotene and α-tocopherol. Both α-carotene and β-carotene were found in all species of green macroalgae analyzed. The content of α-carotene varied from 0.814 Â 0.256 to 71.378 Â 3.550 μg.g -1 fresh weight, being maximum in algae belonging to Caulerpa genus and minimum in Codium decorticatum. The amount of β-carotene varied from 2.322 Â 0.736 to 26.705 Â 7.398 μg.g -1 fresh weight, being minimum in C. mexicana and maximum in Ulva fasciata. Green macroalgae showed lowest retinol equivalents (RE) content in C. mexicana (0.962 Â 0.256 μg.g -1 ) and highest in Caulerpa prolifera (9.014 Â 0.442 μg.g -1 ). A 100 g portion of fresh Caulerpa prolifera would provide 100% of the Recommended Daily Ingestion (RDI) of RE. α-Tocopherol was found in all green macroalgae analyzed but Cladophora prolifera. Minimum and maximum content were observed in Codium decorticatum (15.650 Â 2.634 μg.g -1 fresh weight) and Caulerpa prolifera (383.047 Â 85.254 μg.g -1 fresh weight). Regarding tocopherol equivalents (TE), a 100 g portion of fresh Caulerpa prolifera would provide almost four times the RDI and the same amount of Codium decorticatum would provide only 1 /6 RDI. There was no α-carotene in nine Rhodophyta species. The other eleven showed values between 0.487 Â 0.267 μg.g -1 fresh weight in Solieria filiformis and 3.055 Â 0.278 μg.g -1 fresh weight in Botryocladia occidentalis. β-Carotene was found in all red macroalgae analyzed, exhibiting values of 0.336 Â 0.209 and 4.284 Â 0.607 μg.g -1 fresh weight in Gracilaria caudata and Bryothamnion triquetrum, respectively. The lowest RE was observed in G. caudata (0.056 Â 0.035 μg.g -1 ) and the highest in B. triquetrum (0.764 Â 0.109 μg.g -1 ). A 100 g portion of fresh B. triquetrum would provide less than 1 /10 RDI of RE. α-Tocopherol was not detected in eight species of Rhodophyta. In the other twelve, the content varied from 4.809 Â 1.058 to 31.872 Â 5.883 μg.g -1 fresh weight in Gracilaria ferox and Enantiocladia duperreyi, respectively. A 100g portion of fresh E. duperreyi would provide 1 /3 RDI of TE. Species of Phaeophyta contained β-carotene but no α-carotene. The lowest value for β-carotene was found in Dictyopteris delicatula (0.266 Â 0.198 μg.g -1 fresh weight) and the highest in Padina gymnospora (12.230 Â 2.859 μg.g -1 fresh weight). Regarding RE, the content varied from 0.044 Â 0.033 μg.g -1 to 2.038 Â 0.476 μg.g -1 for D. delicatula and P. gymnospora, respectively. A 100 g portion of fresh P. gymnospora would provide 1 /4 RDI of RE. α-Tocopherol was detected in all Phaeophyta species analyzed. The amount of α-tocopherol was 4.722 Â 2.062 μg.g -1 Lobophora variegata fresh weight and 42.817 Â 31.012 μg.g -1 Dictyota dichotoma fresh weight. A 100 g portion of fresh D. dichotoma would provide 1 /2 RDI of TE

APA, Harvard, Vancouver, ISO und andere Zitierweisen

21

Chaves, Queilane Lemos de Sousa Gomes. „Sediments and macroalgae as bioindicators of trace metals in two parts of the west coasr of CearÃ-brazil“. Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8776.

Der volle Inhalt der Quelle

Annotation:

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Sediments have been used as environmental indicator because of its ability to incorporate and accumulate contaminants, with the surface layers it is possible to analyze the increase or decrease of concentrations of trace metals in the environment, since both metals incorporated from natural sources as the of anthropogenic origin. However the bioindicators more accurately reflect the condition of the metal pollutants in the environment that only the measurements of the concentrations of the metals present in the sediment and water. The present study evaluated geochemistry of sediments and of the rocky substrate, together with the chemistry of three species of macroalgae rhodophytas; Gracilaria sp., Hypnea musciformis and Cryptonemia crenulata. We defined two stretches of beaches located in the state of Ceara, which are important environments for macroalgal banks exploited economically in this state. The excerpts represent two different situations investigated the Coqueiros beach in the municipality of Caucaia near sources of pollution, urban and industrial, and beach Flecheiras located in the municipality of Trairi far from urban centers and industries. The sampling occurred in March 2011 and the materials were analyzed by optical emission spectrometry with inductively coupled plasma (ICP-OES) for sediment and via mass spectrometry with inductively coupled plasma source (ICP-MS) for macroalgae. The results obtained in this study showed high levels of barium and zirconium compared to the crustal average latter with values similar in both study sites (837 Â 499 mg kg-1). Ba levels were higher especially in the beach sediments of Coqueiros (1799-38680 mg kg-1) and lower in the beach sediments Flecheiras (1034 to 2148 mg kg-1). The levels of Ba in the rocky substrate were lower but varied between 387 and 1048 mg kg-1 at the beach of Coqueiros beach against 214-524 mg kg-1 at the Flecheiras beach. Although proximity to anthropogenic sources such as industrial and urban centers could put pressure on the found levels especially barium, natural origins of barium and zirconium anomalies cannot be discarded. Chemical analysis revealed Gracilaria sp. species in which the elements Al, Ba, Be, Ca, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Ge, Hf, Ho, Li, Lu, Mn, Mo , Pb, Rb, Sc, Sn, Sr, Tb, Ti, Tl, Tm, U, V, Y, Yb and Zn observed in individuals from Coqueiros was greater than that observed in specimens Flecheiras. However the concentration of the elements As, Cd and B was significantly higher in Flecheiras Beach. In species Hypnea musciformes the concentration of the elements Mo and especially to Ba, the Coqueiros beach was higher than that observed in specimens beach Flecheiras. The elements As, B, Cd, and Sr, the relative concentration of the samples was higher than Flecheiras referring to individuals of Coqueiros, this difference was very significant for the elements As and Cd in relation to the concentration of trace elements in the species Cryptonemia crenulata were observed only for B and Co. The concentration of B in individuals of Coqueiros was greater than that observed in specimens Flecheiras. And the element Co was higher in samples Flecheiras than that observed in specimens of Coqueiros. Referring to verify bioaccumulation factor for macroalgae Gracilaria sp Beach Coqueiros was significantly higher than that observed in specimens Flecheiras for trace elements Sc (P = 0.038), Sr (P = 0.018) and especially Zn (P = 0.005) and Zr (P = 0.007). The difference was significant for trace element Y (P = 0.057). In samples of macroalgae Cryptonemia crenulata bioaccumulation factor, found in individuals originating from Flecheiras was significantly higher than that observed in specimens Coqueiros only for trace element Co (P = 0.037). The bioindicators more efficient in determining the metals in these sectors is the species Gracilaria sp. bioindicator ideal and one being the bioindicators essential tools in the control and monitoring of trace metals in coastal environments both beaches proved to be contaminated with various toxic elements among much more toxic.
Sedimentos tÃm sido utilizados como indicador ambiental devido sua capacidade de incorporar e acumular elementos contaminantes, com as camadas superficiais Ã possÃvel analisar o aumento ou o decrÃscimo das concentraÃÃes de metais traÃo no ambiente, uma vez que incorporam simultaneamente os metais oriundos de fontes naturais quanto os de origem antrÃpicas. Entretanto os bioindicadores refletem de maneira mais precisa a condiÃÃo dos metais poluentes no ambiente do que somente as medidas das concentraÃÃes dos metais presentes no sedimento e na Ãgua. O presente estudo avaliou a geoquÃmica de sedimentos e do substrato rochoso, juntamente com a quÃmica de trÃs espÃcies de macroalgas rhodophytas; Gracilaria sp., Hypnea musciformis e Cryptonemia crenulata. Delimitamos dois trechos de praias localizadas no estado do CearÃ, os quais sÃo importantes ambientes para bancos de macroalgas explorados economicamente neste estado. Os trechos investigados representam duas situaÃÃes distintas a praia dos Coqueiros situada no municÃpio de Caucaia prÃxima de fontes poluentes, urbana e industrial, e praia Flecheiras situada no municÃpio de Trairi longe de centros urbanos e indÃstrias. A amostragem ocorreu em marÃo de 2011 e os materiais foram analisados via espectrometria de emissÃo Ãptica com plasma indutivamente acoplado (ICP-OES) para os sedimentos e via espectrometria de massas com fonte de plasma indutivamente acoplado (ICP-MS) para as macroalgas. Os resultados obtidos nessa pesquisa mostraram valores altos de bÃrio e zircÃnio em relaÃÃo Ã mÃdia crustal, este Ãltimo com valores mÃdios semelhantes em ambos os locais de estudo (837 Â 499 mg kg-1). Os nÃveis de Ba foram maiores especialmente nos sedimentos da praia dos coqueiros (1799 a 38680 mg kg-1) e em menor nÃvel nos sedimentos da praia de Flecheiras ( 1034 a 2148 mg kg-1). Os nÃveis de Ba no substrato rochoso foi menor mas variou entre 387 e 1048 mg kg-1 na praia dos Coqueiros contra 214 a 524 mg kg-1 na praia de Flecheiras. Embora a proximidade de fontes antrÃpicas como indÃstrias e centros urbanos possa exercer pressÃo sobre os nÃveis especialmente de bÃrio encontrados, origens naturais das anomalias de bÃrio e zircÃnio nÃo podem ser descartadas. As anÃlises quÃmicas na espÃcie Gracilaria sp. revelaram que os elementos Al, Ba, Be, Ca, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Ge, Hf, Ho, Li, Lu, Mn, Mo, Pb, Rb, Sc, Sn, Sr, Tb, Ti, Tl, Tm, U, V, Y, Yb e Zn, verificada nos indivÃduos oriundos de Coqueiros foi maior que a observada nos espÃcimes de Flecheiras. Entretanto a concentraÃÃo dos elementos As, B e Cd foi significantemente maior na Praia de Flecheiras. Na espÃcie Hypnea musciformis a concentraÃÃo dos elementos Mo e, sobretudo, para Ba, na praia dos Coqueiros foi maior que a observada nos espÃcimes da praia de Flecheiras. Os elementos As, B, Cd, e Sr, a concentraÃÃo relativa Ãs amostras de Flecheiras foi maior que a referente aos indivÃduos de Coqueiros, tal diferenÃa foi muito significante para os elementos As e Cd. Em relaÃÃo Ã concentraÃÃo de elementos-traÃo na espÃcie Cryptonemia crenulata foram constatadas apenas para B e Co. A concentraÃÃo de B nos indivÃduos de Coqueiros foi maior que a verificada nos espÃcimes de Flecheiras. E o elemento Co foi maior nas amostras de Flecheiras do que a observada nos espÃcimes de Coqueiros. Referente ao fator de bioacumulaÃÃo verificamos para a macroalga Gracilaria sp da praia dos Coqueiros foi significantemente maior que o observado nos espÃcimes de Flecheiras para os elementos-traÃo Sc (P = 0,038), Sr (P = 0,018) e, sobretudo, Zn (P = 0,005) e Zr (P = 0,007). A diferenÃa foi significante para o elemento-traÃo Y (P = 0,057). Nas amostras da macroalga Cryptonemia crenulata o fator de bioacumulaÃÃo, verificado nos indivÃduos originÃrios de Flecheiras foi significantemente maior que o observado nos espÃcimes de Coqueiros apenas para o elemento-traÃo Co (P = 0,037). Os bioindicadores mais eficientes na determinaÃÃo dos metais nesses setores Ã a espÃcie Gracilaria sp. uma bioindicadora ideal e sendo os bioindicadores ferramentas essenciais no controle e monitoramento de metais traÃo em ambientes costeiros ambas as praias revelaram-se contaminadas por diferentes elementos entre muito tÃxicos a mais tÃxicos.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

22

Pereira, Dinaelza Castelo. „Efeito dos parâmetros ambientais sobre a macroalga Gracilaria domingensis: estratégias de aclimatação e fotoproteção na espécie“. Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-19012015-152336/.

Der volle Inhalt der Quelle

Annotation:

Em seu habitat natural as algas estão sujeitas a ação simultânea de vários fatores, como radiação (fotossinteticamente ativa e ultravioleta), temperatura, salinidade e disponibilidade de nutrientes, entre outros. A variação desses fatores no ambiente natural ocorre de forma coletiva e uma rápida resposta do organismo é determinante pra sua sobrevivência. Neste trabalho foram conduzidos experimentos relacionados aos efeitos da variação nos parâmetros ambientais sobre a macroalga Gracilaria domingensis. Três linhagens cromáticas dessa espécie foram cultivadas no mar, em diferentes épocas do ano (estações chuvosa e seca). Os dados fotossintéticos e bioquímicos foram acessados em uma escala de tempo referente às variações observadas durante o período de luz do dia e em uma escala referente às variações observadas em semanas. Os resultados obtidos a partir de análises dos parâmetros fotossintéticos, conteúdo pigmentar, concentração de glutationa, concentração de aminoácidos tipo micosporina, conteúdo tecidual de carbono, nitrogênio e fósforo, teor de lipídeos e ácidos graxos e rendimento do ágar mostraram alterações no perfil bioquímico e fisiológico da macroalga. Essas alterações foram correlacionadas com os fatores abióticos e sugerem alterações no metabolismo como uma das estratégias de aclimatação da espécie.
In their natural habitat algae are exposed to simultaneous action of various factors, as radiation (photosynthetically active radiation and ultraviolet), temperature, salinity, nutrient availability and others. The variation in these factors in the natural environment occurs collectively and the algae capability for quick response is determinant for survival. In this work, studies related to the effects of environmental variation on the macroalgae Gracilaria domingensis were performed. Three chromatic strains were cultivated in the sea, at different times of the year (dry and rainy seasons). Biochemical and photosynthetic responses were accessed on a daylight time scale and on a week time scale. The reached results for photosynthetic parameters, pigment content, glutathione concentrations, mycosporine-like amino acids concentrations, carbon, nitrogen and phosphorus tissue content, lipids and fatty acids levels and agar yield, revealed the altered biochemical and physiological profile of macroalgae. These changes were environment related and suggest metabolism changes as a strategy used by this organism to acclimate.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

23

Verdura, Brugarola Jana. „Mediterranean macroalgal forests under threat: the effects of ongoing climate change and design of restoration methods“. Doctoral thesis, Universitat de Girona, 2021. http://hdl.handle.net/10803/673885.

Der volle Inhalt der Quelle

Annotation:

Macroalgal forests represent some of the most productive and biodiverse habitats on Earth. In the Mediterranean Sea, species of the genus Cystoseira sensu lato dominate the well-preserved subtidal rocky habitats where they form complex macroalgal communities. However, since the end of the twentieth century, they have suffered important and widespread regressions across the Mediterranean Sea, mainly due to habitat destruction, changes in water quality and overgrazing by sea urchins. As a result, they are often replaced by simpler and less productive communities. The return to pre-disturbed conditions does not necessarily imply the natural recovery of Cystoseira s.l. stands, being active restoration the only feasible alternative to assist the recovery of these populations. Nowadays, climate change, especially gradual warming and acute marine heatwaves (MHWs), represents a global threat for macroalgal forests. In this context, while no studies have reported evidence of warming impacts for Cystoseira s.l. forests, taking into account that Cystoseira s.l. populations have been historically impacted and the expected climate change scenarios for the Mediterranean Sea, it is of paramount importance to know how climate change can affect these species. The results of this thesis show the potential effects of warming on populations of shallow Cystoseira s.l. species, pointing out the relevance of local environmental factors and processes ultimately defining the response of these populations to global trends of climate change. Moreover, we also offer new and promising tools to locally restore these habitats. Overall, our findings are relevant in order to inform local-scale management and conservation plans for safeguarding the persistence of these Mediterranean macroalgal forests
Els boscos de macroalgues representen un dels hàbitats més productius i diversos del planeta. A la Mar Mediterrània, les espècies del gènere Cystoseira sensu lato dominen els fons rocosos submareals de les àrees ben preservades, on formen comunitats d’elevada complexitat. Tanmateix, des de finals del segle XX, aquestes comunitats estan patint importants regressions arreu de la Mediterrània, principalment a causa de la destrucció de l’hàbitat, dels canvis en la qualitat de l’aigua i de la sobrepastura de garotes. En conseqüència, aquestes comunitats sovint són substituïdes per comunitats més simples i menys productives. En molts casos, el fet de revertir les condicions a nivells previs a la pertorbació, no necessàriament implica la recuperació natural dels boscos de Cystoseira s.l. i llavors, la restauració activa esdevé l’única alternativa factible per recuperar aquestes poblacions. Actualment, l’escalfament gradual i els episodis excepcionals de temperatura elevada, derivats del canvi climàtic, representen una amenaça global pels boscos de macroalgues. Encara que no hi ha evidències de l’impacte de l’escalfament en poblacions de Cystoseira s.l., si tenim en compte les pertorbacions que històricament han patit aquestes poblacions així com els escenaris climàtics que es preveuen per a la Mediterrània, és prioritari determinar com el canvi climàtic pot afectar aquestes especies. Els resultats d’aquesta tesi mostren els efectes potencials de l’escalfament en les poblacions d’espècies superficials de Cystoseria s.l., i assenyalen la rellevància dels factors i processos locals, els quals poden definir la resposta d’aquestes poblacions a les tendències globals de canvi climàtic. D’altra banda, es proporcionen noves eines esperançadores per tal restaurar localment aquests hàbitats amb èxit. En general, els nostres resultats són rellevants i aplicables a futurs plans de gestió i conservació a escala local per garantir la persistència d’aquests boscos de macroalgues de la Mediterrània
Programa de Doctorat en Medi Ambient

APA, Harvard, Vancouver, ISO und andere Zitierweisen

24

Santos, Marina Fernandes Barbosa dos. „Predação, eutrofização e respostas metabólicas em comunidades incrustantes de substratos artificiais na Baía da Ilha Grande, RJ“. Universidade do Estado do Rio de Janeiro, 2013. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5153.

Der volle Inhalt der Quelle

Annotation:

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro
As comunidades marinhas são afetadas por diversos fatores, que dentro do contexto de estrutura trófica, podem ser divididos em forças bottom-up (forças ascendentes), como por exemplo, a disponibilidade de nutrientes, e forças top-down (forças descendentes), como por exemplo, a predação. Além de modificações na estrutura das comunidades e populações de organismos, essas forças podem influenciar a produção de metabólitos secundários pelos organismos. O presente trabalho teve como objetivo avaliar o efeito das perturbações ambientais geradas pelas manipulações separadas e interativas de exclusão de macropredadores e enriquecimento com nutrientes sobre a estrutura e sobre as respostas metabólicas de comunidades marinhas incrustantes de substratos artificiais no costão rochoso de Biscaia, Baía da Ilha Grande, RJ. O desenho experimental utilizou blocos de concreto como substrato artificial, os quais foram espalhados aleatoriamente na região de infralitoral do costão rochoso. O experimento compreendeu o uso de blocos Controle (ausência de manipulação) e quatro tratamentos, todos com cinco réplicas cada. Os tratamentos foram: tratamento Exclusão de predação (gaiola contra a ação de macropredadores), tratamento Nutriente (sacos de fertilizante de liberação lenta), tratamento Nutriente + exclusão de predação (gaiola contra ação de macropredadores e sacos de fertilizante de liberação lenta) e o tratamento Controle de artefatos (gaiola semifechada para avaliar geração de artefatos). Uma área de 15 x 15 cm do bloco foi monitorada a cada 20 dias, totalizando dez medições. Foram utilizados métodos de monitoramento visual e digital de porcentagem de cobertura por espécie. O enriquecimento com nutrientes foi avaliado através de medições da concentração dos nutrientes Ortofosfato, Nitrato, Nitrito e Amônio na água do entorno do bloco. Para analisar os possíveis artefatos foi realizado experimento de fluxo de água (método Clod card) e a luminosidade dentro das gaiolas foi medida. Os dados demonstraram modificações na estrutura das comunidades bentônicas incrustantes dos substratos artificiais devido às manipulações realizadas, ou seja, pelo enriquecimento com nutrientes, pela exclusão de predação e pela interação entre os dois fatores (Nutriente + exclusão de predação). Além disso, diferenças metabólicas foram detectadas nas substâncias extraídas dos organismos dos diferentes tratamentos do experimento. Esses resultados indicam a existência de controle top-down e bottom-up sobre a comunidade bentônica do local.
Marine communities can be affected by many factors. Within the context of trophic structure, these factors can be divided into bottom-up forces, such as nutrient availability, and top-down forces, for example, predation. In addition to changes in the structure of communities and populations of organisms, these forces can influence the production of secondary metabolites. This study aimed to evaluate the effect of environmental perturbations generated by separate and interactive manipulations of macropredators exclusion and nutrient enrichment on the communitys structure and the metabolic responses of marine fouling communities of artificial substrates in Biscaia rocky shores, Ilha Grande Bay, RJ. The experimental design used concrete blocks as artificial substrate. The blocks were randomly scattered in the sub tidal region of the rocky shore. The experiment involved the use of Control blocks (no manipulation) and four treatments with five replicates each. The treatments were: Predator Exclusion treatment (cages excluding macropredators), Nutrient treatment (packs with slow-releasing fertilizer), Nutrient + predator exclusion treatment (cage excluding macropredators and packs with slow-releasing fertilizer), and Artifacts control treatment (semi-closed cage to assess artifacts effects). An area of 15 x 15 cm of each block was monitored every 20 days, totaling ten measurements. Visual and digital species percentage coverage methods were used. To assess nutrient water enrichment, we measured concentration of nutrients (orthophosphate, nitrate, nitrite and ammonium) in the water. To evaluate possible cages experimental artifacts, a water flow test (Clod card method) was performed, and luminosity inside the cages was measured. Data demonstrated changes in the structure of fouling communities on artificial substrates due to the manipulations performed, i.e., the nutrient enrichment, predation exclusion and the interaction between these two factors (Nutrient + predator exclusion). Moreover, differences were observed in substances extracted from organisms in different treatments of the experiment. These results indicate the existence of top-down and bottom-up controls on the benthic community of this site.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

25

Sfecci, Estelle. „Valorisation de biocides d’invertébrés marins méditerranéens“. Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4039.

Der volle Inhalt der Quelle

Annotation:

Ces travaux de thèse portent sur l’étude chimique d’espèces marines échantillonnées en Méditerranée. Dans le cadre du projet VALBIM, co-financé par la région PACA et en étroite collaboration avec la société BioPreserv à Grasse mais également avec la Mycoteca Universitatis Taurinensis (MUT) de l’Université de Turin, nous avons isolé et caractérisé 21 molécules dont 14 se sont avérées nouvelles. L’étude de l’algue Caulerpa taxifolia a conduit à la caulerpényne et à quatre nouveaux dérivés de l’acide pyruvique sulfatés. Les travaux sur l’ascidie Polysyncraton sp. ont conduit aux bolascidines A-D, quatre nouveaux métabolites de type bolaamphiphiles dont il n’existe pas à notre connaissance d’équivalent naturel ou synthétique. La première étude chimique de l’éponge Hexadella racovitzai a conduit à deux dérivés de la bromotyrosine, la psammapline A et une nouvelle molécule, la 4-Osulfatocyclobispsammapline A. Par ailleurs, trois nouvelles crambescines C1, conjointement avec une crambescine A2 déjà répertoriée, ont été isolées de Crambe crambe. L’étude du champignon marin Stachybotrys chartarum, isolé de l’éponge Aplysina cavernicola, a conduit à la satratoxine H et à deux nouveau dérivé, la 2,3-dihydrosatratoxine H et l’épi-chartarutine G, ainsi qu’à trois dérivés stachybotrylactame déjà répertoriés dans la bibliographie. Les différents métabolites ont été évalués pour leurs propriétés antibactériennes et cytotoxiques. Ces travaux ont bénéficié de nouvelles approches analytiques (calculs des spectres de dichroïsme circulaire électroniques par TDDFT, réseaux moléculaires) permettant de renforcer l’intérêt des études liées à l’écologie chimique et à la recherche de nouvelles molécules bioactives potentiellement valorisables dans différents domaines
This PhD work focuses on the chemical study of marine species sampled in the Mediterranean Sea. As part of the VALBIM project, cofinanced by the region PACA and in close collaboration with the SME BioPreserv in Grasse but also with the Mycoteca Universitatis Taurinensis (MUT) of the University of Turin, we have isolated and characterized 21 molecules in total.14 of them were never reported before. The study of the seaweed Caulerpa taxifolia led to caulerpenyne and four new sulphated pyruvic acid derivatives. The work on the ascidian Polysyncraton sp. led to bolascidins A-D, four new metabolites which belong to the bolaamphiphile family, which, to the best of our knowledge, have no natural or synthetic equivalent. The first chemical study of the sponge Hexadella racovitzai led to two bromotyrosine derivatives, psammapline A and a new molecule, 4-O-sulfatocyclobispsammapline A. In addition, three new C1 crambescins, together with one crambescine A2 already reported, have been isolated from Crambe crambe. For all isolated marine invertebrate metabolites, the producer(s) remain(s) to be explored. The study of the marine fungus Stachybotrys chartarum, isolated from the sponge Aplysina cavernicola, led to satratoxin H and three stachybotrylactam derivatives already reported in the literature, and to 2,3-dihydrosatratoxin H and epi-chartarutine G, two new natural products. The different metabolites were evaluated for their antibacterial and cytotoxic properties. This work benefited from new analytical approaches (calculations of electronic circular dichroïsm spectra by TDDFT, molecular networking) and reinforced the interest of studies related to chemical ecology and search for new bioactive molecules to be valorized in different areas

APA, Harvard, Vancouver, ISO und andere Zitierweisen

26

Brugneaux, Sophie. „Régulation des communautés algales par les macro-herbivores dans les communautés récifales des Antilles françaises : (Guadeloupe, Martinique, Saint-Barthélémy)“. Thesis, Antilles-Guyane, 2012. http://www.theses.fr/2012AGUY0522/document.

Der volle Inhalt der Quelle

Annotation:

Une étude des facteurs influençant la composition et la répartition spatiale des abondances algales dans les communautés récifales des Antilles françaises et plus spécifiquement de Guadeloupe a été réalisée. Le rôle joué par les oursins diadème est plus particulièrement étudié. Les principaux compartiments des communautés récifales et les facteurs d'influence susceptibles de jouer un rôle dans la régulation du compartiment algal ont été dimensionnés sur 22 stations des Antilles françaises. Pour cela plusieurs indicateurs ont été testés. Après une description de chaque compartiment biotique (algues, herbivores, prédateurs), une recherche des facteurs influençant les caractéristiques du compartiment algal a été menée à trois échelles spatiales, à l'aide d'analyses statistiques non paramétriques, notamment des analyses canoniques des redondances et des correspondances. Puis, une recherche des facteurs influençant la répartition des oursins diadème a été également menée. Si les deux guildes d'herbivores étudiées (poissons et oursins diadème) ont un impact significatif sur l'abondance de gazon algal, seuls les poissons herbivores ont la capacité d'exercer cette influence à l'échelle des récifs de Guadeloupe et cette influence ne s'étend pas aux autres catégories algales. Notamment les phéophycées. A l'échelle de l'ensemble des îles étudiées, les analyses effectuées n'ont pas permis de mettre en évidence l'influence des herbivores sur la régulation des abondances algales. Les oursins diadèmes sont en faible densité dans les iles antillaises étudiées. Plusieurs facteurs susceptibles de participer à leur répartition en taille et en abondance sont identifiés
A study of factors influencing the composition and spatial distribution of algal abundance in the French Caribbean reef communities and more specifically in Guadeloupe was conducted. The role of diadema sea urchins was particularly studied. For that, 22 stations in the French Antilles were selected and several indicators tested. After a description of each biotic compartment (algae, herbivore, predators), a search for factors influencing the characteristics of the algal compartment was conducted at three spatial scale, using non-parametric statistical analyses, including canonical correspondence analyses (cca) and redundancy analyses (rda). Then a search for the factors influencing the distribution of diadema sea urchins was also conducted. If the two guilds of herbivores (diadema sea urchin and fish) have a significant impact on the abundance of algal turf, only herbivorous fish was found to have an influence in the reefs of Guadeloupe and that influence was not observed on other algal groups, including phaeophyceae. At the scale of all the islands, the analyses did not enable to show the influence of herbivores in the regulation of algal abundance. The density of sea urchins was found to be low in the studied sites. Several factors likely to influence their distribution in size and their abundance were identified

APA, Harvard, Vancouver, ISO und andere Zitierweisen

27

Lopes, Pedro Henrique Martins. „Estudos de Cultura de Tecidos, In Vitro, de Macroalgas Marinhas da EspÃcie Gracilaria birdiae“. Universidade Federal do CearÃ, 2008. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6571.

Der volle Inhalt der Quelle

Annotation:

nÃo hÃ
Macroalgas marinhas constituem um recurso vital para a economia de diversos paÃses e tem sido exploradas ao redor do globo devido a sua capacidade de produÃÃo de fico colÃides como o Ãgar, carragenina e alginatos, bem como pelo seu espectro de utilizaÃÃo, seja na indÃstria de alimentos, de fertilizantes e na medicina. Estudos sobre a induÃÃo, cultivo e reorganizaÃÃo de calos, tem representado um importante papel nas tÃcnicas de cultura de tecidos e suas aplicaÃÃes. Em diferentes tecidos cultivados in vitro, a utilizaÃÃo de reguladores de crescimento Ã de importÃncia primordial para o estabelecimento da competÃncia e determinaÃÃo, condiÃÃes necessÃrias para a formaÃÃo de calos e regeneraÃÃes. No presente estudo foram testados os efeitos de uma auxina e de uma citocinina, em diferentes concentraÃÃes de Ãgar em meio ASP 12-NTA. O efeito do Ãcido indolacÃtico (AIA) e da 6-benzilaminopurina (BAP) foram testados em explantes de macroalgas de espÃcie Gracilaria birdiae, em separado, com duas concentraÃÃes de 0,5 mg/L e 0,8 mg/L e em conjunto, nas concentraÃÃes de 1:5 mg/L e 5:1 mg/L. Com relaÃÃo a concentraÃÃo de Ãgar, foram testadas duas concentraÃÃes, com 0,5% e 0,8% para todos os tratamentos. Para o processo de esterilizaÃÃo foram aplicados um fungicida (nistatina) e um antibiÃtico (ciprofloxacina), alÃm de iodopovidona e hipoclorito de sÃdio. Todo o experimento foi conduzido em cÃmara de germinaÃÃo, com temperatura de 25 Â 2oC e fotoperÃodo de 16hs de luz e 08hs escuro, salinidade de 30 Â 2â e pH em torno de 7,6, durante aproximadamente 60 dias. Ao final de 50 dias de cultivo, foi observada a formaÃÃo de calos e de processos de regeneraÃÃo indireta dos mesmos. Os resultados foram submetidos a tratamentos estatÃsticos de anÃlise de contigÃncia atravÃs do Quiquadrado (χ2 ), onde foram observadas diferenÃas significativas entre a incidÃncia de calos e regeneraÃÃes e os nÃveis de Ãgar estudados. Ou seja, nos tratamentos onde foram utilizados nÃveis de Ãgar de 0,8%, apresentaram o maior nÃmero de regeneraÃÃes
Seaweed consists in a vital resource to the economy of many countries and it has been explored all over the world thanks to its capacity of producing colloids such as agar, carrageen and sodium alginate as well as the useful aspect either in food industry, fertilizers or medicine area. Studies on induction, cultivation and callus reorganization have been shown an important issue on tissue culture technique and its usage. In different tissue experience in vitro the usage of regulating growth is so fundamental to establish the competence and necessary conditions to callus formation and regeneration. In this present study has been tested the auxin and citocinin effects in different dosages of agar in ASP 12-NTA. The indolacetic acid effect and 6- benzilalaminopurine have been tested as well in seaweed in the species Gracilaria birdiae with two separated doses, 0,5mg/L and 0,8mg/L and together in concentration of 1:5mg/L and 5;1mg/L. Regarding to agar concentration, it has been tested two concentrations with 0,5% and 0,8% in all treatments. As to sterilization process has been done with fungicide (nistatina) and antibiotic (ciprofloxacin) besides iodopovidona and the sodium hypochlorite. The complete experiment had been lead in a germination chamber with 25Â2ÂC and photoperiod of more or less 16 hs of light and 08hs dark and 30,2â saltiness, pH around 7,6 within 60 days approximately. In more or less 50 days of cultivation had been noticed callus formation and regeneration process therein. The results had been underwent by statistic analyze treatments of contingent through (x2) where many meaningful different observations had been checked in callus and regeneration and the agar levels studied, that is to say the agar level treatments in 0,8% presented a major number of regeneration

APA, Harvard, Vancouver, ISO und andere Zitierweisen

28

Lucena, Leidson Allan Ferreira de. „Estrutura e composição de macroalgas de manguezais hipersalinos do Rio Grande do Norte, Brasil: Diversidade e suas correlações com as variáveis ambientais“. Universidade Estadual da Paraíba, 2012. http://tede.bc.uepb.edu.br/tede/jspui/handle/tede/2467.

Der volle Inhalt der Quelle

Annotation:

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-08-19T13:11:18Z No. of bitstreams: 1 PDF - Leidson Allan Ferreira de Lucena.pdf: 2690352 bytes, checksum: af138cc1f96427cfccb006ba3e949852 (MD5)
Made available in DSpace on 2016-08-19T13:11:18Z (GMT). No. of bitstreams: 1 PDF - Leidson Allan Ferreira de Lucena.pdf: 2690352 bytes, checksum: af138cc1f96427cfccb006ba3e949852 (MD5) Previous issue date: 2012-02-17
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Marine and coastal environments in the world have been facing in the last years a notable environmental degradation process. Macroalgae are the main constituent phytobenthics communities, and they are essentials to the establishment of balance and resilience these ecosystems. The mangroves swamps are coastal environments and may be ecotones, because they are an interposition of continental and marine environments overlap, in scalar patterns. The organisms found have become resistants with the strong transition that occur, such as Bostrychietum macroalgae, where they have formed the most homogeneous communities of mangroves swamps wide world. However, the mangrove swamps typically fall within one of two broad categories of classification: mainland or oceanic island. The mainland mangroves are home biological communities resistants with the strong phisico-chemical variations, and of oceanic island mangroves form on shallow banks or in lagoonal areas well separated from the mainland. In Brazil, mangroves swamps are solely of type mainland, which form the major area these forests in the coastal South America. This ecosystemic pattern is normally associate with fluvial systems – the estuaries, and is combined with many biological disorders, such as salinity and flooding tolerance. The estuarines environments which gives different environments in biological diversity, where can check trait plasticity between population. The estuaries can be classified in three categories: Positives, Low -Inflow and Negatives. Brazilian mangroves there are solely Positives Estuaries where the addition of freshwater river, discharge and thaw exceed the loss by evaporation or freezing, where longitudinal density gradients that drive a net volume output to the ocean. But in semi-arid region, Northeast of Brazil, there are some ecosystemics patterns. The estuarine-mangals show negative characters that are hypersaline and/or reverse, because the flow of freshwater systems are barely making them with a longitudinal density gradient with the opposite sign in relation the positive estuaries and salt concentrations rarely exceed 50. Two rivers (Casqueira and Shark rivers), located in setentrional coast of Rio Grande do Norte state, Macau city, have shown how negatives estuaries (hypersaline and reverse), and are composition species of macroalgae many specific and have a very dynamic environment. A pilot study conducted in April 2010 have been showing one ficoflora visually diverse, that have colonized muddy substrates in great abundance unusually and then resembles those typically found in marine environments typical. To contribute to the scientific knowledge of macroalgae found, this study has as main objective: to do a investigation about composition and structure macroalgae of two hypersaline mangroves, so to observe the effects of hipersalinity and physic-chemical patterns in the dynamics of algal communities. Therefore, this work establishes a comparative relationship between communities and population of seaweeds this environments.
Os ambientes costeiros e marinhos no mundo vem sofrendo um considerável processo de degradação nos últimos anos. As macroalgas, principais constituintes das comunidades fitobentônicas, são fundamentais para o estabelecimento do equilíbrio e resiliência dos ecossistemas nestes ambientes. Em padrões escalares, os manguezais são ambientes costeiros e podem ser considerados ecótonos, por haver uma interposição de ambientes continental e marinho sobrepostos. Os organismos existentes nestes ambientes tornam-se resistentes a forte transição que ocorre, a exemplo as macroalgas do grupo “Bostrychietum”, que formam comunidades homogêneas na maioria dos manguezais do mundo. Os manguezais podem estar distribuídos em duas categorias: os continentais, que abrigam comunidades biológicas resistentes às fortes variações físico - químicas, e as de ilhas oceânicas que formam bancos de águas rasas ou áreas lagunares bem separadas do continente. No Brasil, os manguezais são exclusivamente do tipo continentais, exceção os de Fernando de Noronha, com a maior área costeira na América do Sul. Este padrão ecossistêmico normalmente está associado a sistemas fluviais que são os estuários e é associado a diversos distúrbios biológicos, a exemplo das variações da salinidade; o que confere ambientes distintos em diversidade biológica, conferindo plasticidade fenotípica entre as populações. Os estuários podem ser classificados de três tipos: Positivos, “Low-Inflow” e Negativos. Manguezais brasileiros estão comumente associados a estuários Positivos que são aqueles em que a adição de água doce do rio, chuva, descarga e derretimento do gelo excedem a perda por evaporação ou congelamento, estabelecendo um gradiente de densidade longitudinal em que dirige um volume líquido de saída para o oceano. Porém, na região semi -árida do Nordeste brasileiro, ocorrem algumas particularidades ecossistêmicas. Os ambientes mangue-estuarinos demonstram características hipersalinas, sendo também considerados negativos e/ou inversos, pois, por situarem em regiões áridas e semi- áridas, a vazão de água doce nesses sistemas é praticamente nula o que os tornam com um gradiente de densidade longitudinal com o sinal oposto em relação aos estuários positivos e as concentrações de sal raramente inferiores a 42. Dois manguezais (Rio Casqueira e Tubarão), localizados no litoral setentrional do Estado do Rio Grande do Norte, município de Macau, revelaram-se de caráter negativo e hipersalinos, além de serem bastante peculiares em termos de composição de espécies macroalgais e da própria dinâmica do ambiente. Um estudo-piloto realizado no mês de Abril de 2010 revelou uma ficoflora visualmente diversa, que atipicamente coloniza substratos lamacentos em grande abundância e que se assemelha àquelas tipicamente encontradas em ambientes marinhos típicos. Visando contribuir com o conhecimento científico acerca das macroalgas encontradas, o presente estudo tem como principal objetivo: realizar uma investigação da composição e estrutura da comunidade de macroalgas de dois manguezais hipersalinos no intuito de observar os efeitos da hipersalinidade sob padrões físico-químicos na dinâmica das comunidades algais, estabelecendo uma relação comparativa entre as populações e comunidades de algas marinhas dos ambientes estudados.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

29

Pires, Kelma Maria dos Santos. „Avaliação sazonal de carotenóides provitamina A (α– e β– caroteno) e vitamina E (α–tocoferol) em macroalgas marinhas pertencentes a família Caulerpacea (Divisão Chlorophyta)“. reponame:Repositório Institucional da UFC, 2007. http://www.repositorio.ufc.br/handle/riufc/18443.

Der volle Inhalt der Quelle

Annotation:

PIRES, Kelma Maria dos Santos. Avaliação sazonal de carotenóides provitamina A (α– e β– caroteno) e vitamina E (α–tocoferol) em macroalgas marinhas pertencentes a família Caulerpacea (Divisão Chlorophyta). 2007. 94 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortalezza-CE, 2007
Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-18T14:11:47Z No. of bitstreams: 1 2007_dis_kmspires.pdf: 561534 bytes, checksum: 2fbf133b889f47da3a32efc273c3f7ec (MD5)
Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-18T14:12:01Z (GMT) No. of bitstreams: 1 2007_dis_kmspires.pdf: 561534 bytes, checksum: 2fbf133b889f47da3a32efc273c3f7ec (MD5)
Made available in DSpace on 2016-07-18T14:12:01Z (GMT). No. of bitstreams: 1 2007_dis_kmspires.pdf: 561534 bytes, checksum: 2fbf133b889f47da3a32efc273c3f7ec (MD5) Previous issue date: 2007
Marine macroalgae are sources of a great variety of beneficial compounds such as minerals, dietary fibers and vitamins. The aim of this work was to verify seasonal variation upon both provitamin A carotenoids (α- and β-carotene) and vitamin E (α-tocopherol) contents in five species of the marine green macroalga Caulerpa both fresh and oven-dried at 40°C for 15 h. The contents in dried algae were compared to those in fresh algae to evaluate the losses after drying. Algal material was collected monthly from January to December 2006, in Pacheco Beach, Caucaia, Ceará. Analyses of α- and β-carotene and α-tocopherol were carried out in extracts 1:10 (p/v) for fresh alga and 1:20 (p/v) for dried alga using aqueous methanol (90:10, v/v). They were saponified with 5% KOH and partitioned into n-hexane, which was then evaporated. The residues were suspended in 1 mL methanol prior to HPLC analyses. Aliquots of 100 μL were injected in a HPLC system consisting of a Waters Spherisorb-Hichrom S5 ODS-2 column (4.6 x 250 mm) and a mobile phase of methanol:tetrahydrofurane (90:10, v/v), delivered at 1.5 mL min-1. The detector was set at 450 nm for α- and β-carotene and 290 nm for α-tocopherol. Chromatograms were registered at UnicornTM version 5.0. All samples showed α- and β-carotene and α-tocopherol, but their distribution along the year was variable. In general, the contents of α-carotene were greater than those of β-carotene. The losses of α- and β-carotene varied between 10% and 94%. In order to be considered an excellent source of vitamin A, the daily consumption would be 52 g to 689 g of fresh alga or 42 g to 469 g of dried alga. α-Tocopherol was detected in all samples except in dried C. racemosa collected in March. Similar to the distribution of α- and β-carotene along the year, α-tocopherol contents varied too. Losses varied from 22% to 91%. Daily portions to supply 50% of the Recommended Daily Allowance (RDA) would be 11 g to 168 g of fresh alga or 13 g to 70 g of dried alga. Amounts of vitamin A (retinol equivalents) and vitamin E (tocopherol equivalents) in all algae analyzed were not very different from most vegetables normally consumed
As algas marinhas são fontes de uma grande variedade de compostos benéficos para o homem, dentre os quais se destacam os minerais, as fibras dietárias e as vitaminas (A, B, C e E). O objetivo deste trabalho foi verificar a existência de variação sazonal nos teores de α- e β-caroteno (carotenóides provitamina A) e de α-tocoferol (vitamina E), em cinco espécies de macroalgas marinhas pertencentes ao gênero Caulerpa (Família Caulerpaceae, Divisão Chlorophyta), “in natura” e desidratada. Os conteúdos desses nutrientes nas algas desidratadas foram comparados com aqueles nas algas “in natura”, com o objetivo de verificar se houve alteração pelo processo de desidratação. As espécies de macroalgas marinhas foram coletadas mensalmente, de janeiro a dezembro de 2006, durante as marés baixas na Praia do Pacheco, Caucaia- CE. As análises de α- e β-caroteno e α-tocoferol foram realizadas a partir da extração da alga em metanol-água (90:10) nas proporções 1:10 (p/v), nas amostras “in natura”, e 1:20 (p/v), nas desidratadas, saponificação com hidróxido de potássio 5% por 30 min a 70°C e partição em n-hexano que foi evaporado sob corrente de ar. O resíduo foi suspenso em 1 mL de metanol no momento da análise cromatográfica e 100 μL foram injetados manualmente. O sistema cromatográfico consistiu em uma coluna Waters Spherisorb-Hichrom S5ODS-2 (4,6 x 250 mm) e uma fase móvel constituída de metanol:tetrahidrofurano (90:10, v/v), com fluxo de 1,5 mL min-1. O detector foi ajustado em 450 nm e 292 nm e os cromatogramas registrados através do sistema UnicornTM versão 5.0. Todas as espécies de Caulerpa “in natura” e desidratadas analisadas no presente trabalho apresentaram tanto α-caroteno quanto β-caroteno e as suas distribuições mostraram diferenças ao longo dos doze meses de coleta. De um modo geral, os teores de α-caroteno foram superiores aos de β-caroteno. As perdas nos conteúdos de carotenóides provitamina oscilaram entre 10% e 94%. Para que as algas analisadas neste trabalho fossem consideradas fontes excelentes de vitamina A seria necessário que as porções consumidas diariamente variassem de 52 g a 689 g, quando consumidas “in natura” ou de 42 g a 469 g, quando desidratadas. As cinco espécies analisadas neste trabalho apresentaram α-tocoferol, tanto nas amostras “in natura” quanto nas desidratadas, com exceção de C. racemosa coletada em março que após ser submetida a secagem não foi detectado α- tocoferol, e sua distribuição foi variável ao longo do ano. Nos teores de α- tocoferol foi observado perdas que variaram de 22 a 91%. As porções que deveriam ser consumidas diariamente para que as espécies de Caulerpa estudadas fossem capazes de fornecer 1/2 da IDR são relativamente pequenas, devendo oscilar entre 11 g e 168 g, quando “in natura”, ou entre 13 g e 70 g, quando desidratadas. As quantidades de retinol equivalente e α-tocoferol equivalente nas algas analisadas no presente trabalho não diferiram muito daquelas encontradas nos vegetais normalmente consumidos

APA, Harvard, Vancouver, ISO und andere Zitierweisen

30

Sousa, Márcia Barbosa de. „Extração e quantificação de α-Caroteno, β-Caroteno e α-Tocoferol em macroalgas marinhas utilizando cromatografia líquida de alta eficiência em fase reversa“. reponame:Repositório Institucional da UFC, 2005. http://www.repositorio.ufc.br/handle/riufc/18485.

Der volle Inhalt der Quelle

Annotation:

SOUSA, Márcia Barbosa de. Extração e quantificação de α-Caroteno, β-Caroteno e α-Tocoferol em macroalgas marinhas utilizando cromatografia líquida de alta eficiência em fase reversa. 2005. 75 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de engenharia de Pesca, Fortaleza-Ce, 2005
Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-19T14:26:29Z No. of bitstreams: 1 2005_dis_mbsousa.pdf: 522874 bytes, checksum: 4c3c5e46b154d052d5b541a5f9541f73 (MD5)
Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-19T14:26:44Z (GMT) No. of bitstreams: 1 2005_dis_mbsousa.pdf: 522874 bytes, checksum: 4c3c5e46b154d052d5b541a5f9541f73 (MD5)
Made available in DSpace on 2016-07-19T14:26:44Z (GMT). No. of bitstreams: 1 2005_dis_mbsousa.pdf: 522874 bytes, checksum: 4c3c5e46b154d052d5b541a5f9541f73 (MD5) Previous issue date: 2005
The aim of this work was to evaluate the potential of 32 marine macroalga species belonging to Chlorophyta, Rhodophyta and Phaeophyta as sources of α-carotene, β-carotene and α-tocopherol. Both α-carotene and β-carotene were found in all species of green macroalgae analyzed. The content of α-carotene varied from 0.814 ± 0.256 to 71.378 ± 3.550 μg.g -1 fresh weight, being maximum in algae belonging to Caulerpa genus and minimum in Codium decorticatum. The amount of β-carotene varied from 2.322 ± 0.736 to 26.705 ± 7.398 μg.g -1 fresh weight, being minimum in C. mexicana and maximum in Ulva fasciata. Green macroalgae showed lowest retinol equivalents (RE) content in C. mexicana (0.962 ± 0.256 μg.g -1 ) and highest in Caulerpa prolifera (9.014 ± 0.442 μg.g -1 ). A 100 g portion of fresh Caulerpa prolifera would provide 100% of the Recommended Daily Ingestion (RDI) of RE. α-Tocopherol was found in all green macroalgae analyzed but Cladophora prolifera. Minimum and maximum content were observed in Codium decorticatum (15.650 ± 2.634 μg.g -1 fresh weight) and Caulerpa prolifera (383.047 ± 85.254 μg.g -1 fresh weight). Regarding tocopherol equivalents (TE), a 100 g portion of fresh Caulerpa prolifera would provide almost four times the RDI and the same amount of Codium decorticatum would provide only 1 /6 RDI. There was no α-carotene in nine Rhodophyta species. The other eleven showed values between 0.487 ± 0.267 μg.g -1 fresh weight in Solieria filiformis and 3.055 ± 0.278 μg.g -1 fresh weight in Botryocladia occidentalis. β-Carotene was found in all red macroalgae analyzed, exhibiting values of 0.336 ± 0.209 and 4.284 ± 0.607 μg.g -1 fresh weight in Gracilaria caudata and Bryothamnion triquetrum, respectively. The lowest RE was observed in G. caudata (0.056 ± 0.035 μg.g -1 ) and the highest in B. triquetrum (0.764 ± 0.109 μg.g -1 ). A 100 g portion of fresh B. triquetrum would provide less than 1 /10 RDI of RE. α-Tocopherol was not detected in eight species of Rhodophyta. In the other twelve, the content varied from 4.809 ± 1.058 to 31.872 ± 5.883 μg.g -1 fresh weight in Gracilaria ferox and Enantiocladia duperreyi, respectively. A 100g portion of fresh E. duperreyi would provide 1 /3 RDI of TE. Species of Phaeophyta contained β-carotene but no α-carotene. The lowest value for β-carotene was found in Dictyopteris delicatula (0.266 ± 0.198 μg.g -1 fresh weight) and the highest in Padina gymnospora (12.230 ± 2.859 μg.g -1 fresh weight). Regarding RE, the content varied from 0.044 ± 0.033 μg.g -1 to 2.038 ± 0.476 μg.g -1 for D. delicatula and P. gymnospora, respectively. A 100 g portion of fresh P. gymnospora would provide 1 /4 RDI of RE. α-Tocopherol was detected in all Phaeophyta species analyzed. The amount of α-tocopherol was 4.722 ± 2.062 μg.g -1 Lobophora variegata fresh weight and 42.817 ± 31.012 μg.g -1 Dictyota dichotoma fresh weight. A 100 g portion of fresh D. dichotoma would provide 1 /2 RDI of TE
O objetivo deste trabalho foi avaliar o potencial de 32 espécies de algas marinhas das divisões Chlorophyta, Rhodophyta e Phaeophyta como fontes de α-, β-caroteno e α-tocoferol. Todas as Chlorophyta apresentaram α- e β-caroteno. O teor de α-caroteno variou de 0,814 ± 0,256 a 71,378 ± 3,550 μg.g -1 peso fresco, sendo mais elevado no gênero Caulerpa e mais baixo em Codium decorticatum. O teor de β-caroteno variou de 2,322 ± 0,736 a 26,705 ± 7,398 μg.g -1 peso fresco, sendo mínimo em C. mexicana e máximo em Ulva fasciata. Com relação ao retinol equivalente (RE), as algas verdes apresentaram mínimo em C. mexicana (0,962 ± 0,256 μg.g -1 ) e máximo em Caulerpa prolifera (9,014 ± 0,442 μg.g -1 ). Considerando a ingestão de 100 g de alga fresca por dia, uma porção de Caulerpa prolifera forneceria 100% da ingestão diária recomendada (IDR). Todas as Chlorophyta apresentaram α-tocoferol, exceto Cladophora prolifera. Os teores mínimo e máximo foram 15,650 ± 2,634 e 383,047 ± 85,254 μg.g -1 peso fresco em Codium decorticatum e Caulerpa prolifera, respectivamente. Com relação ao tocoferol equivalente (TE), a ingestão diária de 100 g de Caulerpa prolifera fresca forneceria quase quatro vezes mais que a IDR e a mesma porção de Codium decorticatum seria responsável por apenas 1 /6 da IDR. Dentre as Rhodophyta estudadas, nove não apresentaram α-caroteno. Nas outras onze, o seu teor oscilou de 0,487 ± 0,267 μg.g -1 em Solieria filiformis a 3,055 ± 0,278 μg.g -1 peso fresco em Botryocladia occidentalis. β-Caroteno foi encontrado em todas as espécies de algas vermelhas com valores mínimo e máximo de 0,336 ± 0,209 e 4,284 ± 0,607 μg.g -1 de peso fresco em Gracilaria caudata e Bryothamnion triquetrum, respectivamente. Com relação ao RE, foi observado valor mínimo em Gracilaria caudata (0,056 ± 0,035 μg.g -1 ) e máximo em Bryothamnion triquetrum (0,764 ± 0,109 μg.g -1 ). Uma porção de 100 g de Bryothamnion triquetrum fresca forneceria um pouco mais de 1 /10 da IDR. Oito espécies de Rhodophyta estudadas não apresentaram α-tocoferol. Nas outras doze, seu conteúdo oscilou entre 4,809 ± 1,058 e 31,872 ± 5,883 μg.g -1 peso fresco, em Gracilaria ferox e Enantiocladia duperreyi, respectivamente. Em relação ao TE, a ingestão diária de 100 g da alga E. duperreyi fresca forneceria 1 /3 da IDR. As Phaeophyta estudadas apresentaram apenas β-caroteno, com valores mínimo e máximo em Dictyopteris delicatula e Padina gymnospora, iguais a 0,266 ± 0,198 e 12,230 ± 2,859 μg.g -1 peso fresco, respectivamente. Com relação ao RE, o teor mínimo foi observado em Dictyopteris delicatula (0,044 ± 0,033 μg.g -1 ) e máximo em Padina gymnospora (2,038 ± 0,476 μg.g -1 ). Considerando a ingestão diária de 100 g de alga fresca, uma porção de P. gymnospora seria responsável por 1 /4 da IDR. As Phaeophyta apresentaram α-tocoferol, com valor mínimo em Lobophora variegata igual a 4,722 ± 2,062 μg.g -1 peso fresco e máximo em Dictyota dichotoma, igual a 42,817 ± 31,012 μg.g -1 peso fresco. Considerando a ingestão de 100 g de alga fresca por dia, uma porção de Dictyota dichotoma forneceria 1 /2 da IDR de TE

APA, Harvard, Vancouver, ISO und andere Zitierweisen

31

Schiener, Peter. „Bioethanol production from macroalgae“. Thesis, University of the Highlands and Islands, 2014. https://pure.uhi.ac.uk/portal/en/studentthesis/bioethanol-production-from-macroalgae(d1c0fd4d-3a91-4d17-be4f-0b7b2af86e11).html.

Der volle Inhalt der Quelle

Annotation:

Seaweed biomass has been identified as a potential fermentation substrate for third generation biofuel processes due to its high carbohydrate content and its potential for mass cultivation without competing for agricultural land, fresh water and fertilisers. This thesis aimed to develop and advance existing processes to convert brown seaweeds into bioethanol. The main kelp species chosen as biomass candidates were Laminaria digitata, Laminaria hyperborea, Saccharina latissima and Alaria esculenta due to their abundance in Scottish waters and their identified potential for mariculturing. These kelp species were chemically characterised to identify seasonal variations, to recommend suitable seaweed candidates for bioethanol production and predict best harvest times. This has only been demonstrated before on one species - L. digitata. The chemical composition analyses were carried out over a 14 months sampling period, which focused on the storage carbohydrates laminarin and mannitol and the structural carbohydrates alginate, cellulose, fucoidan and xylose. In addition to carbohydrates the protein, nitrogen, carbon, polyphenol, ash and metal content was also profiled. Chemical profiling identified all four kelps as potential fermentation candidates, where maximum carbohydrate contents coincided with lowest ash and polyphenol content, usually seen in autumn. Biomass pre-treatment and saccharification are up-stream processes aimed at enhancing extraction of carbohydrates and converting those into fermentable substrates. Conversion of seaweed biomass into fermentation substrate evaluated acids and enzymes for seaweed pre-treatment and saccharification. Methodologies focused on optimising saccharification yields were developed to identify process critical parameters and develop methods for routine analysis of seaweed biomass. Results demonstrated that dilute acid hydrolysis was were less effective in releasing fermentable sugars, and also resulted in higher salinities compared to enzymatic hydrolysis using hemicellulosic and cellulosic enzymes, which were the preferred method of saccharification. All seaweeds in this thesis were assessed as fermentation substrates using the yeasts S. cerevisiae and P. angophorae, that principally ferment glucose or mannitol, respectively. Small-scale fermentation assays were developed for both yeasts to maximise ethanol yields and achieve process robustness. Both yeasts achieved a maximum ethanol yield of 0.17 g g-1 using Laminaria spp. On the basis of results, S. cerevisiae is recommended as the most useful yeast at this present point for ethanol fermentation from seaweed hydrolysates because of its tolerance to high salinity and ethanol concentrations. As salinity can negatively affect non-halotolerant enzymes, isolation of marine microorganisms was therefore carried out with the aim to highlight their enzymatic potential in seaweed saccharification. This was achieved through the isolation of two members of the genus Pseudoalteromonas, where saccharification yields using crude intracellular enzyme preparations exceeded those of dilute acids. In addition, the fermentative potential of microbial isolates as future ethanologenic strains was also evaluated. Understanding of the metabolic pathways is needed to fully assess the potential of those strains for genetic alteration. In conclusion, this thesis has demonstrated that up to ca. 20 g l-1 of ethanol can be produced from kelp species that grow on the west coast of Scotland. The procedure developed and used to produce ethanol requires further development, specifically the need for ethanol-fermenting microorganisms that can utilize mannitol and alginate; use of marine-adapted enzymes for saccharifiction; and the development of processes to achieve substrate concentration with reduced salinities. Comparison of theoretical ethanol yields from seaweed biomass with ethanol yields from terrestrial crops showed that the complete utilisation of all three major seaweed carbohydrates (laminarin, mannitol and alginate) from kelp species is needed for the process to be able to compete with 1st generation biofuel processes.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

32

Júnior, Cícero Alves Lima. „Ritmos circadianos em Gracilaria birdiae (Rhodophyta): oscilação do desempenho fotossintético e caracterização enzimática da nitrato redutase“. Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-26042013-153410/.

Der volle Inhalt der Quelle

Annotation:

Os ritmos circadianos coordenam grande parte dos mecanismos fisiológicos, principalmente no metabolismo do nitrogênio, inclusive a assimilação do nitrato, que é a forma de nitrogênio mais incorporada pelos organismos fotossintéticos marinhos. Sua assimilação é feita pela enzima nitrato redutase (NR) que é regulada de forma sistêmica e em vários níveis: transcricional, pós-transcricional e pós-traducional. Tal modulação é exercida por diversos fatores como nitrato, luz, glutamato, quinases e por fatores de transcrição centrais do ritmo circadiano. A fotossíntese fornece os esqueletos de carbono e poder redutor para a incorporação do nitrogênio na síntese de glutamato. Gracilaria birdiae é uma macroalga endêmica do litoral brasileiro e ainda precisa de mais estudos em fisiologia, apesar da sua grande importância econômica. Este estudo desenvolveu um novo protocolo para o ensaio em larga escala da atividade enzimática da NR e analisou a oscilação do desempenho fotossintético ao longo do dia em G. birdiae. A alga, proveniente do Rio Grande do Norte, foi isolada a nível unialgal e apresentou uma taxa de crescimento relativo diário de 6,5% em laboratório. O novo protocolo descrito propõe as seguintes adaptações: amostragem de 20 mg de biomassa algal em vez de 100 mg, extrato bruto com 100 µL em vez de 1 mL, ensaio enzimático de 50 µL e parada da reação com sulfanilamida em vez de EtOH/ZnSO4. Estas modificações permitem o ensaio enzimático da NR semi-purificada de 8 testes com réplicas experimentais e biológicas e controle negativo (96 ensaios no total) em 3 horas. A caracterização enzimática demonstrou os seguintes parâmetros ótimos para atividade máxima: tampão fosfato pH 8, temperatura 25°C, 60 minutos de incubação, 1,25 mMol de nitrato e 50 µMol de NADH. A atividade máxima de 5,4 ± 0,7 nMol.min-1.mg-1 de proteínas e o KM 6 ± 2,2 µMol.L-1 para NADH e de 109 ± 11 µMol.L-1 para o nitrato. A enzima não apresentou atividade na presença de NADPH e demonstrou atividade 48 vezes maior que no protocolo inicial. Descrevemos um método preciso e reprodutível para análise em larga escala da atividade da NR que pode ser utilizado em estudos comparativos de cinética enzimática da NR de diferentes espécies ou em estudos de ritmos biológicos. A análise do desempenho fotossintético, feita em coletas de 15 mg de alga, foi caracterizada pela fluorescência da clorofila, demonstrando os seguintes parâmetros máximos: taxa de transporte de elétrons relativa (rETR) de 15,29 µMol elétrons.m-2.s-1, eficiência fotossintética (alfa) de 0,37 fótons/elétrons, irradiância de saturação (IK) foi de 41,32 µE.m-2.s-1 e houve fotoinibição a partir de 300 µE.m-2.s-1. Apenas o parâmetro alfa apresentou oscilação significativa em claro constante e manteve o período de 24 horas, apesar de ter diminuído sua amplitude em 50%. Isso pode ser devido a um controle pelo mecanismo central dos ritmos circadianos sobre proteínas ou pigmentos ligados ao fotossistema II, influenciando na capacidade de transformação de fótons em elétrons. Paralelamente, a aclimatação da alga à luz constante pode ter levado a uma queda na produção de pigmentos e fotoxidação, justificando a queda nos valores médios de alfa. G. birdiae é uma alga com grande importância econômica e ecológica e este estudo, ligado a outros trabalhos de fisiologia, confirma seu grande potencial para estabelecimento como organismo modelo para estudos fisiologia e fotossíntese
Circadian rhythms control most of physiological processes, including nitrate assimilation. This nutrient is the most incorporated form of nitrogen by marine plants and its assimilation is made by the nitrate reductase enzyme (NR) that is highly regulated in all levels expression, since mRNA transcription until protein degradation. Many factors coordinate this regulation, including the nitrate itself, light glutamate, kinases and by transcription factors of the central oscillator of the circadian rhythms. Photosynthesis also plays an especial role in NR regulation through carbon skeleton and NADPH synthesis that allows the last step of nitrate assimilation: glutamate synthesis. Gracilaria birdiae is an endemic marine rhodophyte from Brazil that still lacks physiological and molecular studies despite its extensively exploitation for agar-agar extraction. This study aimed the development of a large scale enzymatic assay of NR (NRA) and the analysis of daily oscillation of photosynthesis performance for G. birdiae. The algae, collected ant Rio Grande do Norte state, was isolated to a unialgal level and presented an average of relative daily growth rate of 6.5% in laboratory. The new protocol here described proposes the following adaptations for NRA: sampling of 20 mg instead of 100 mg, 100 µL of crude extract rather than 1 mL, NRA in 50 µL in place of 1 mL and reaction stop with sulphanilamide instead of an EtOH/ZnSO4 system. These changes allow the assay of the semi-purified NR of 24 samples all with its experimental and biological triplicates and negative control in 3 hours. Phosphate buffer at pH 8, 25°C, 60 minutes of incubation, 1.25 mMol of nitrate and 50 µMol of NADH. The maximum activity was 5.4 ± 0.7 nMol.min-1.mg-1 of protein and a KM of 6 ± 2.2 µMol.L-1 for NADH and of 109 ± 11 µMol.L-1 for nitrate. NR didn\'t show any activity in the presence of only NADPH as the electron donor and showed and 48 times greater activity in the new protocol, compared to the old one. We describe here an accurate and reproducible method for large scale NRA that can be used in comparative studies of NR kinetics or in biological rhythms of NR. The analysis of photosynthetic performance, made in 15 mg sampling of algal biomass, was characterized through chlorophyll fluorescence, revealing the maximum values of these parameters: relative electrons transfer rate (rETR) of 15,29 µMol elétrons.m-2.s-1, photosynthetic efficiency (the alpha parameter) of 0,37 photons/electrons, the saturating irradiance (IK) was 41.32 µE.m-2.s-1 and there was photoinhibition below the irradiance of 300 µE.m-2.s-1. The only variable that oscillated during the continuous light experiment and maintained the 24-hour period was the Alfa parameter, besides its 50% lower amplitude. This oscillation can be due to an endogenous control of the central circadian oscillator into proteins or pigments bound to the photosystem II, influencing the capacity of photon-electron transformation. At the same time, the acclimation to constant light could have driven the algae to a damping of pigment production and photoxidation, what explains the fall of alpha average values. G. birdiae is an alga with great economic and ecological relevance and this study confirms the potential for its establishment as a model organism.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

33

Sousa, MÃrcia Barbosa de. „ComposiÃÃo centesimal e variaÃÃo do teor de vitaminas em macroalgas marinhas verdes Ulva fasciata e U. lactuca (Ulvales,Chlorophyta), coletadas na Praia do Pacheco, Caucaia-CearÃ“. Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7523.

Der volle Inhalt der Quelle

Annotation:

As macroalgas marinhas apresentam elevadas quantidades de proteÃnas, fibras, sais minerais e vitaminas lipossolÃveis, possuem conteÃdo de lipÃdios relativamente baixo, embora seus Ãcidos graxos constituintes tenham elevado grau de insaturaÃÃo. A maioria desses compostos varia de acordo com a Ãpoca do ano e com as condiÃÃes ecolÃgicas que podem estimular ou inibir a biossÃntese desses nutrientes. Os carotenÃides sÃo pigmentos acessÃrios encontrados em macroalgas marinhas que estÃo envolvidos na captaÃÃo da luz e na fotoproteÃÃo. Vitamina E Ã o termo genÃrico utilizado para fazer referÃncia a um grupo de substÃncias encontradas na natureza, os tocoferÃis e os tocotrienÃis, que possuem diferentes graus de atividade vitamÃnica. Nas algas, os tocoferÃis sÃo encontrados na membrana dos cloroplastos, predominantemente como alfa-tocoferol protegendo o aparato fotossintÃtico. Este trabalho teve como objetivo analisar a composiÃÃo quÃmica e a variaÃÃo sazonal do teor de vitaminas nas espÃcies Ulva fasciata e U. lactuca coletadas na Praia do Pacheco no municÃpio de Caucaia, CearÃ no ano de 2007 durante as marÃs de sizÃgia. Em seguida, elas foram divididas em duas porÃÃes de aproximadamente 100 g cada. A primeira porÃÃo foi macerada com o auxÃlio de nitrogÃnio lÃquido atÃ a obtenÃÃo de farinha algal, que foi utilizada para a quantificaÃÃo de alfa- e beta-caroteno e de alfa- e delta-tocoferol. A outra parte foi submetida Ã desidrataÃÃo em estufa a 40ÂC por 15 horas, transformadas em uma farinha fina, utilizada para a determinaÃÃo da composiÃÃo centesimal (proteÃna total, lipÃdio, cinza e carboidrato) e para a extraÃÃo e quantificaÃÃo de carotenÃides provitamina A (alfa- e beta-caroteno) e tocoferÃis (alfa- e delta-tocoferol). Para o estudo de carotenos e tocoferÃis, o material algal âin naturaâ e desidratado foi submetido Ã extraÃÃo com metanol, saponificaÃÃo com hidrÃxido de potÃssio e partiÃÃo em n-hexano. Para a anÃlise cromatogrÃfica foi usada uma coluna Waters Spherisorb S5 ODS-2 (4,6 x 250 mm) e fase mÃvel de MeOH: THF (95:5, v/v), com fluxo de 1,5 mL min-1. O monitor foi ajustado em 450 e 292 nm, para a leitura simultÃnea de carotenos e tocoferÃis. As espÃcies analisadas apresentaram teores de proteÃna total, carboidratos e cinzas que variaram ao longo do ano. Os teores de lipÃdios foram sempre baixos. Nas amostras de U. fasciata e U. lactuca âin naturaâ e desidratadas foram detectadas as presenÃas de alfa- e beta-caroteno em quantidades variÃveis ao longo dos doze meses de coleta. Os menores teores de carotenÃides foram detectados nos meses de outubro e novembro em U. fasciata e U. lactuca âin naturaâ coincindindo com a maior radiaÃÃo solar. Foram detectadas as presenÃas de alfa- e delta-tocoferol em teores variÃveis ao longo do ano nas espÃcies U. fasciata e U. lactuca âin naturaâ e desidratadas. NÃo foi possÃvel perceber uma relaÃÃo Ãbvia entre os teores de alfa- e delta-tocoferol e coloraÃÃo, idade da planta ou radiaÃÃo solar mais ou menos intensa.
Marine macroalgae have been shown to possess high amounts of proteins, dietary fibers, minerals and lipossoluble vitamins, and a relatively low lipid content, although the constituent fatty acids are highly unsaturated. Most of these compounds vary with regard to the time of year and ecological conditions, which may stimulate or inhibit the biosynthesis of these nutrients. Carotenoids are accessory pigments found in marine macroalgae, involved in the capture of sunlight and photoprotection. Vitamin E is the generic term used to refer to a group of substances found in nature, tocopherols and tocotrienols, which present different degrees of vitaminic activity. In macroalgae, tocopherols are found in the chloroplast membrane, predominantly as alpha-tocopherol, protecting the photosynthetic apparatus. The aim of this thesis was to analyze the centesimal composition (total protein, lipids, ash and carbohydrates) and seasonal variation of the vitamin content in the species Ulva fasciata and U. lactuca, collected on Pacheco Beach in Caucaia, CearÃ, in 2007 during low tides. The material was divided in two portions of approximately 100 g each. The first portion was macerated with liquid nitrogen until the algal powder was obtained, and was used for the quantification of alpha- and beta-carotene, and alpha- and delta-tocopherol. The other portion was dehydrated in an oven at 40ÂC for 15 h, ground into a fine powder, and used for the determination of the centesimal composition and for the extraction and quantification of carotenoids provitamin A (alpha- and beta-carotene) and tocopherols (alpha- and delta-tocopherol). In the study of carotenes and tocopherols, the âin naturaâ and dehydrated algal material were submitted to extraction with methanol, saponification with potassium hydroxide, and partition with n-hexane. For the chromatographic analysis, a Waters Spherisorb S5 ODS-2 (4.6 x 250 mm) column was used, with MeOH: THF (95:5, v/v) as the mobile phase, delivered at 1.5 mL min-1. The monitor was adjusted to 450 and 292 nm for the simultaneous reading of carotenes and tocopherols. The species analyzed presented total protein, carbohydrate, and ash content which varied along the year. The lipid content was low throughout. In the U. fasciata e U. lactuca âin naturaâ and dehydrated samples, the presence of alpha- and beta-carotene was detected in varying quantities during the twelve month collection period. The lowest carotenoid contents were detected in October and November in U. fasciata and U. lactuca âin naturaâ, coinciding with the increased solar radiation. The isomers alpha- and delta-tocopherol were detected in varying amounts throughout the year in the U. fasciata and U. lactuca species âin naturaâ and dehydrated. No immediately evident relation was found between the alpha- and delta-tocopherol contents and coloration, plant age, or increased or decreased solar radiation.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

34

Ross, Michael Eric. „Wastewater treatment by filamentous macroalgae“. Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31512.

Der volle Inhalt der Quelle

Annotation:

An increase in anthropogenic activity has led to the heightened levels of pollution entering aquatic systems. These excessive concentrations of heavy metals, nitrogen (N), and phosphorus (P) in water bodies can lead to several adverse impacts, such as eutrophication and human health risks. Therefore, the removal of pollutants from wastewaters, prior to their discharge into the natural environment, is of paramount importance. However, conventional wastewater treatment (WWT) technologies have their limitations; for instance, large capital/operational costs, and incomplete removal of contaminants. Therefore, innovative and more effective treatment technologies are required. Macro-algae typically have high growth and solar energy conversion rates, and are able to sequester nutrients, utilise CO2, and adsorb metals from aquatic environments. Therefore, algae may have potential applications in WWT. Furthermore, costs could be negated by the production of renewable algal biomass which may have a variety of commercially exploitable applications. However, issues such as poor selection of species or cultivation systems, and a lack of understanding of the influence of biological, chemical and physical factors, particularly in a highly dynamic wastewater environments, has led to varied results and prevented algal WWT becoming a widespread reality. In this thesis the algae Cladophora coelothrix and Cladophora parriaudii were studied as potential organisms for implementation into WWT. In addition to the features mentioned above, Cladophora was selected due to its ubiquity, filamentous morphology, which minimises harvesting costs, as well as their natural dominance and bloom forming behaviour in nutrient-rich environments. The influence of dewatering techniques, environmental factors, and nutrient regime upon the growth, nutrient/metal removal, and biochemical composition of the biomass were assessed. The first aspect of the thesis was an abiotic screening process, in order to investigate the robustness of Cladophora and its suitability for WWT applications on a fundamental level. Good rates of growth (4-13.3% d-1) and nutrient removal (45.2-99.9%) were observed throughout the screening process, except under the most extreme of conditions, e.g. pH 3. This indicated that Cladophora are potentially suitable for treating a broad range of wastewaters and merit further research to improve its potential applicability for WWT applications and commercial realisation. For instance, developing a reliable and accurate method for fresh weight (FW) assessment and hence productivity estimation. The determination of growth rate via FW measurement is one of the most basic aspects of algal biology, yet no standardised method exists for filamentous macro-algae. A variety of FW methods were systematically assessed in terms of accuracy and physiological impact. Methods involving mechanical pressing to dewater the biomass resulted in >25% reduction in the final biomass yield, compared to control cultures. The best method for FW determination employed a reticulated spinner, which was rapid, reliable, and easily standardised. Furthermore, this approach ensured accurate growth estimation with minimal physiological impact, measured as growth, maintenance of structural integrity and nutrient removal. This indicates that the method developed has the potential for widespread application in macro-algal cultivation, as such the method was employed throughout this thesis. The influence of nutrient regime on growth, biochemical composition, and bioremediation capacity was studied for both species of Cladophora. The nutrient regimes tested, representative of a broad variety of wastewaters, included four different N/P ratios, four N sources (ammonium, nitrate, nitrite and urea), and six different equimolar N source combinations provided at two N/P ratios. There were clear differences in performance between the two species, with higher rates of growth observed in all instances by C. parriaudii (4.75-11.2% d-1 vs. 3.98-7.37% d-1). Furthermore, ammonium was removed preferentially, whereas urea was removed secondarily. However, the presence of urea in the medium enhanced growth and uptake of the other co-existing N-forms, and yielded a carbohydrate-rich biomass (37.6-54% DW). These findings demonstrate that algal strain selection is important for treating wastewaters with specific nutrient profiles. In addition, results from this study suggest that nutrient regimes can be tailored to produce biomass with certain properties or characteristics, which make it suitable for further, potentially commercially viable, applications, such as metal biosorption. Since the biochemical characteristics of algal biomass were shown to be affected by nutrient regime, the final chapter describes research investigating the influence of nutritional history on metal biosorption. C. parriaudii was cultivated under different nutrient regimes to produce biomass of varying biochemical composition. This biomass was then used for metal removal, with maximum removal rates ranging from 1.08-2.35 mmol g1, 0.3-0.62 mmol g-1, 0.22-0.48 mmol g-1, and 0.43-0.61 mmol g-1 for Al2+, Cu2+, Mn2+, and Pb2+, respectively. Observations from this work indicate that metal removal is achieved by various mechanisms including adsorption, ion exchange, complexation and micro-precipitation, and that the biosorption efficacy is dependent upon the number and type of functional groups present, which are in turn influenced by the cultures nutrient regime. Overall, this study demonstrates the inter-relatedness of biological, chemical, and physical factors on algal growth, nutrient removal, biochemical composition, and metal biosorption. Results from this work have highlighted the need for standardisation in protocols, increased understanding of the influence of algal selection and nutrient characteristics in bioremediation, and highlighted the importance of considering biological aspects, specifically nutritional history, in biosorption studies.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

35

Khnayfes, Marcos Amoyr [UNESP]. „Efeitos da textura e heterogeneidade de substratos artificiais em função da velocidade da correnteza e da escala temporal sobre as comunidades de macroalgas de ambientes lóticos“. Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/87884.

Der volle Inhalt der Quelle

Annotation:

Made available in DSpace on 2014-06-11T19:23:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-01Bitstream added on 2014-06-13T20:10:30Z : No. of bitstreams: 1 khnayfes_ma_me_rcla.pdf: 366930 bytes, checksum: c69a2b0e76bf67d5eb27107a48b4bb18 (MD5)
A heterogeneidade do habitat vem sendo considerada a maior discriminadora da diversidade das comunidades em sistemas lóticos. Esta pode ser caracterizada por variáveis específicas tais como velocidade da correnteza, temperatura, tipo de substrato, nutriente e luz. Diversos estudos se propõem a investigar a relação entre heterogeneidade de habitat e a distribuição das comunidades algais, através de estratégias metodológicas que envolvem o uso e aplicação de critérios de amostragem a partir das comunidades algais dispostas em substratos artificiais. Levando-se em conta que muitas investigações sugerem que o tipo de substrato pode ser a principal variável influenciando a distribuição espacial e temporal das comunidades lóticas e, que raríssimos estudos são aplicados às macroalgas de ambientes lóticos e que estas, juntamente com as briófitas, são as principais responsáveis pela produção primária nestes ecossistemas, o presente estudo foi proposto com os seguintes objetivos: 1) fazer uma análise de biomassa, composição florística e riqueza macroalgal diante de diferentes texturas de substratos artificiais, bem como de padrões de heterogeneidade criados a partir de combinações de fragmentos dos substratos artificiais testados, na tentativa de se aproximar dos fenômenos ocorridos em rochas naturais; 2) avaliação da textura e heterogeneidade do substrato sob duas condições de velocidade de correnteza em um riacho artificial; e 3) avaliação da textura e heterogeneidade do substrato ao longo da escala temporal de 109 dias em riachos naturais. Os resultados mostraram que a abundância global das comunidades de macroalgas foi bastante baixa e semelhante entre os tratamentos de textura e heterogeneidade nos dois experimentos, sugerindo que os níveis de rugosidade e de complexidade do substrato não apresentaram relevante influência sobre as coberturas percentuais...
The heterogeneity of habitat has been considered the most discriminating of the diversity of communities in lotic systems. This can be characterized by specific variables such as velocity, temperature, substrate type, nutrient and light. Several studies are proposed to investigate the relationship between habitat heterogeneity and distribution of algal communities through strategic methods that involve the use and application of criteria for sampling from algal communities on artificial substrates placed. Taking into account that many investigations suggest that the substrate may be the main variable influencing the spatial and temporal distribution of lotic communities and that very few studies are applied to the lotic macroalgae and that these, together with bryophytes, are mainly responsible for primary production in these ecosystems, this study was proposed with the following objectives: 1) make an analysis of biomass, floristic composition and richness on macroalgal of different types of artificial substrates as well as patterns of heterogeneity created from combinations of fragments of artificial substrates tested in an attempt to get closer to the phenomena occurring in rock natural, 2) evaluation of texture and heterogeneity of the substrate with two different water flow in an artificial stream, and 3) evaluation of texture and heterogeneity of the substrate over the fluctuation time of 109 days in natural streams. The results showed that the overall abundance of macroalgal communities was quite low and similar between the treatment of texture and variety in both experiments, suggesting that levels of roughness and complexity of the substrate showed no relevant influence on the coverage percentages of the communities investigated. The velocity, in turn, influenced both the abundance and wealth, these decreasing at higher intensity. Richness was lower, particularly at higher surface... (Complete abstract click electronic acces below)

APA, Harvard, Vancouver, ISO und andere Zitierweisen

36

Krupek, Rogerio Antonio [UNESP]. „Análise da variação espaço-temporal em diferentes escalas sobre a distribuição ecológica das comunidades de macroalgas de duas bacias de drenagem da região centro-sul do estado do Paraná“. Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/100631.

Der volle Inhalt der Quelle

Annotation:

Made available in DSpace on 2014-06-11T19:30:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-04Bitstream added on 2014-06-13T18:41:18Z : No. of bitstreams: 1 krupek_ra_dr_rcla.pdf: 699780 bytes, checksum: a064995df1e9361f54c1d222e4471c1a (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
O presente trabalho teve como objetivo principal analisar a influência da heterogeneidade espaçotemporal, em diferentes escalas, sobre a distribuição de comunidades de macroalgas em uma área localizada na região centro-sul do estado do Paraná. Para ambos os estudos (espacial e temporal) seguiram-se os mesmos procedimentos amostrais. As escalas espaciais avaliadas foram: bacia de drenagem (Rio das Pedras e Rio Marrecas), mesohábitat (remanso e corredeira) e microhábitat (unidades amostrais com área de 0,05 m2), além dos níveis de sombreamento (aberto e sombreado). As amostragens foram realizadas em locais que apresentavam visível crescimento de algas. Um número igual de unidades amostrais “sem alga” também foi aleatoriamente avaliado. Dentro de cada unidade amostral foram avaliados os parâmetros bióticos (riqueza e abundância de espécies) e as variáveis ambientais locais (irradiância, velocidade da correnteza, profundidade, riqueza e diversidade do substrato). Em adição, para cada riacho, foram tomadas medidas das seguintes variáveis ambientais regionais: temperatura da água, oxigênio dissolvido, condutividade, pH e turbidez. No estudo espacial, um total de dez riachos foram avaliados por bacia de drenagem, sendo identificados 29 táxons. As diferenças entre as escalas espaciais estiveram muito mais relacionadas com características particulares de cada grupo (divisão e tipo morfológico) do que propriamente com a composição das espécies. A única distinção observada na estrutura das comunidades esteve relacionada com os diferentes níveis de sombreamento, o que evidencia a importância do regime de luz como fator determinante na distribuição espacial destes organismos. Em adição, a velocidade da correnteza também foi importante neste aspecto, já que maior desenvolvimento algal foi observada nestes ambientes. Em síntese, as características locais...
This study aimed to analyze the influence of spatial and temporal heterogeneity at different scales, the distribution of macroalgal communities in an area located in the mid-southern of Parana state. For both studies (spatial and temporal) followed the same sampling procediments. The spatial scales evaluated were: drainage basin (Pedras river and Marrecas river), mesohabitat (riffles and pools) and microhabitat (sampling units an area of 0,05 m2), beyond to shading levels (open and shaded). The sampling units were positioned in places that hat visible growth of algae. A same number of sample units “without algae” also were randomly evaluated. Within each sampling unit were evaluated biotic parameters (richness and abundance of species) and the local variables (irradiance, current velocity, depth, richness and diversity of substrate). In addition, for each stream were taken of the following regional variables: water temperature, oxygen saturation, specific conductance, pH and turbidity. In the spatial study, a total of ten streams were evaluated by drainage basin, being identified 29 taxa. The differences between the spatial scales were more related to particular characteristics of each group (division and morphological type) than properly with the species composition. The only difference observed in community structure was related to the different levels of shading, which shows the importance of light as a determining factor in the spatial distribution of these organisms. In addition, the current velocity was also important in this aspect, as greater algal development was observed in these environments. In summary, the local characteristics had the greatest influence that the regional variables in the spatial distribution of macroalgal communities evaluated. For the temporal study, one stream was monthly evaluated in each drainage basin. A total of 16 taxa were identified. Although... (Complete abstract click electronic access below)

APA, Harvard, Vancouver, ISO und andere Zitierweisen

37

Pacheco, Mariana Rodrigues. „Macroalgas marinhas associadas a bancos de rodolitos do infralitoral do Espírito Santo, Brasil“. Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-11052011-144911/.

Der volle Inhalt der Quelle

Annotation:

Macroalgas têm sido descritas no Brasil desde a região entremarés até cerca de 120 metros de profundidade na plataforma continental. O objetivo deste trabalho foi a caracterização da flora marinha bêntica em bancos de rodolitos entre 20-30 metros de profundidade, do infralitoral sul do estado do Espírito Santo. Os métodos utilizados neste projeto incluíram a coleta meticulosa de material através de mergulho autônomo, que preserva o material mais frágil em contraste com a utilização de dragagem. Estudos no infralitoral do estado do Espírito Santo são muito escassos. Esta flora é conhecida principalmente pela análise de material arribado nas praias e proveniente de algumas dragagens e mergulhos. Este trabalho procura contribuir para o inventário da flora de algas marinhas brasileiras, assim como contribuir para o conhecimento da biodiversidade de macroalgas enfocando especialmente a flora do infralitoral através de um estudo sistemático, descrevendo e ilustrando os aspectos mais importantes das espécies encontradas. Foram identificados 138 táxons de algas marinhas, sendo 77,5% (107 táxons) representantes do Filo Rhodophyta, 11,6% (16 táxons) representantes do Filo Chlorophyta e 10,9% (15 táxons) representantes da Classe Phaeophyceae. Observou-se também que a riqueza de espécies de macroalgas no inverno decresce acentuadamente em relação ao período de verão. Esta redução na riqueza de espécies pode ser explicada pela instabilidade gerada nos bancos de rodolitos no período de inverno, pela maior frequência de tempestades. Dois gêneros são referidos pela primeira vez para o Atlântico ocidental, Tsengia K. C.Fan & Y.P. Fan (Halymeniales/Rhodophyta) e Pugetia Kylin (Gigartinales/Rhodophyta). Foram registradas duas novas ocorrências para a flora marinha brasileira, Erythrocladia endophloea M.A. Howe e uma espécie ainda não identificada de Pseudobryopsis Berthold. Dezesseis novas ocorrências foram registradas para o estado do Espírito Santo: Acrochaetium liagorae Børgesen, Anotrichium yagii (Okamura) Baldock, Caulerpa brachypus Harvey, Ceramium affine Setchell & N.L.Gardner, Chondria dasyphylla (Woodward) C. Agardh, Dasya caraibica M.A. Howe, Dasya rigidula (Kützing) Ardissone, Derbesia vaucheriaeformis (Harvey) J. Agardh, Erythrocladia pinnata W.R. Taylor, Gracilaria blodgettii Harvey, Griffithsia globulifera Harvey ex Kützing, Nitophyllum cf. punctatum (Stackhouse) Greville, Rhipiliopsis stri (S. Earle & J.R. Young) Farghaly & Denizot, Streblonema invisibile Hoyt, Udotea unistratea D.S. Littler & M.M. Littler e Yuzurua poiteaui (J.V. Lamouroux) Martin-Lescanne var. gemmifera (Harvey) Sentíes, M.T. Fujii & Díaz-Larrea. Para Platoma cyclocolpum (Montagne) F. Schmitz, Platoma sp. e Dudresnaya sp., espécies de rara ocorrência na costa brasileira, são fornecidas informações sobre estruturas reprodutivas e estádios de pós-fertilização. Estas novas adições na flora indicam a importância da realização de pesquisas em áreas pouco estudadas da costa brasileira. O infralitoral ainda representa uma lacuna no conhecimento das algas e outros organismos marinhos. Estudos que utilizam mergulho autônomo geralmente fornecem novidades para a comunidade científica, principalmente no que diz respeito às espécies frágeis que não resistem aos métodos de dragagem.
In Brazil, macroalgae have been reported from the intertidal to about 120 meters depth on the continental shelf. The aim of this study was to characterize the marine benthic flora in banks of rhodoliths between 20-30 meters depth, in the subtidal zone of southern Espirito Santo state. The methods utilized in this project included a careful collection of material through SCUBA diving, which preserves the more fragile material in contrast to the use of dredging. Studies on the sublittoral flora of the state of Espirito Santo are very scarce. This flora has been studied mainly through material casted ashore on the beaches and through some material from dredging and diving. This study seeks to contribute to the inventory of the Brazilian marine algae flora and also contribute to the knowledge of the biodiversity of the algae, focusing on sublittoral flora, by a systematic study, through descriptions and illustrations of the most important characteristics of sampled species. This research resulted in the identification of 138 taxons of marine algae being 77,5% (107 taxons) Rhodophyta, 11,6% (16 taxons) Chlorophyta and 10,9% (15 taxons) Phaeophyceae. It was also observed that macroalgae species richness decreases sharply during winter season, in comparison to summer period. This reduction in species richness could be attributed to the instability generated in the rhodoliths banks during winter, by the increasing of storm conditions. In this work we recorded two new genera for the tropical Western Atlantic, Tsengia K. C.Fan & Y.P. Fan (Halymeniales/Rhodophyta) and Pugetia Kylin (Gigartinales/Rhodophyta), and two new records for the Brazilian marine flora: Erythrocladia endophloea M.A. Howe and a species of Pseudobryopsis Berthold not yet identified. Sixteen new occurences were also registered for the state of Espírito Santo: Acrochaetium liagorae Børgesen, Anotrichium yagii (Okamura) Baldock, Caulerpa brachypus Harvey, Ceramium affine Setchell & N.L.Gardner, Chondria dasyphylla (Woodward) C. Agardh, Dasya caraibica M.A. Howe, Dasya rigidula (Kützing) Ardissone, Derbesia vaucheriaeformis (Harvey) J. Agardh, Erythrocladia pinnata W.R. Taylor, Gracilaria blodgettii Harvey, Griffithsia globulifera Harvey ex Kützing, Nitophyllum cf. punctatum(Stackhouse) Greville, Rhipiliopsis stri (S. Earle & J.R. Young) Farghaly & Denizot, Streblonema invisibile Hoyt, Udotea unistratea D.S. Littler & M.M. Littler and Yuzurua poiteaui (J.V. Lamouroux) Martin-Lescanne var. gemmifera (Harvey) Sentíes, M.T. Fujii & Díaz-Larrea. There were provided informations about reproductive structures and stages of postfertilization from Platoma cyclocolpum (Montagne) F. Schmitz, Platoma sp. and Dudresnaya sp., species that occur rarely in Brazilian coast. These new additions to the flora indicate the importance of conducting research in less studied areas of the Brazilian coast. The subtidal zone still represents a gap in the knowledge of the algae and other marine organisms. Studies using SCUBA diving often yields new references especially regarding fragile species that can not resist to the dredging method.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

38

Tonetto, Aurélio Fajar [UNESP]. „Efeitos da irradiância e da composição espectral da luz sobre o estabelecimento e desenvolvimento de comunidades de macroalgas lóticas em substratos artificiais“. Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/87902.

Der volle Inhalt der Quelle

Annotation:

Made available in DSpace on 2014-06-11T19:23:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-02Bitstream added on 2014-06-13T20:49:52Z : No. of bitstreams: 1 tonetto_af_me_rcla.pdf: 1077078 bytes, checksum: f064a230b49104d5525789cc80a0787e (MD5)
Os efeitos provocados pela variação quantitativa e qualitativa da luz incidente sobre a estrutura das comunidades de macroalgas lóticas em riachos da região Centro-Sul do estado do Paraná foram investigados a partir de experimentos utilizando-se amostradores com substratos artificiais que modulam a quantidade e qualidade da luz incidente. Os resultados reveleram que as respostas das divisões algais isoladamente foram mais claras do que àquelas observadas para as comunidades de macroalgas como um todo. As algas verdes mostraram-se melhores adaptadas as condições com maiores energias luminosas. A espécie de cianobactéria registrou clara preferência por comprimentos de onda mais longos (faixa do vermelho). As algas vermelhas apesar de apresentarem baixos valores de abundância, aparentemente, preferiram condições levemente sombreadas e, como as cianobactérias, apresentaram maiores valores de abundância quando submetidas a luz vermelha. Neste contexto, o aparato fotossintético característico de cada divisão algal parece ser determinante para os seus comportamentos ecológicos, uma vez que desempenham funções adaptativas diante das diferentes condições de luminosidade
The effects of light intensity and quality on the structure of lotic macroalgal communities in streams from the mid-southern region of Paraná State were investigated using artificial substrata that simulate different levels of light and specific wavelengths. The results showed that the abundance values of each algal divisions were clearer to that observed to global macroalgae communities. The green algae were better adaptated on higher light energies conditions. The cianobacteria species reported a clear preference to longer wavelengths (red light). Red algae, on the other hand, despite of the low abundance values, apparently prefer lightly shaded conditions and like blue-green algae, they showed better colonization on the red light. In this context, the characteristic photosynthetic apparatus of each division seems to be determinant to the ecological behavior of these communities once they play an important adaptative role face to the different light conditions

APA, Harvard, Vancouver, ISO und andere Zitierweisen

39

Almeida, Fernanda Vital Ramos de [UNESP]. „Flora e distribuição ecológica de comunidades de macroalgas lóticas de fragmentos florestais da região noroeste do estado de São Paulo“. Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/87904.

Der volle Inhalt der Quelle

Annotation:

Made available in DSpace on 2014-06-11T19:23:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-02Bitstream added on 2014-06-13T18:50:15Z : No. of bitstreams: 1 almeida_fvr_me_rcla.pdf: 5323757 bytes, checksum: 55eb2e9b9c051e2271a31350a6e1ee7e (MD5)
Vários estudos envolvendo flora e distribuição de comunidades de macroalgas lóticas já foram desenvolvidos na região noroeste do estado de São Paulo; entretanto, nunca foi realizada qualquer abordagem sobre macroalgas lóticas em fragmentos florestais remanescentes, aspecto mais relevante deste estudo. Foram testadas as seguintes hipóteses: (1) entre as regiões/biomas estudados no estado de São Paulo, o atual trabalho deve apresentar maior similaridade florística com Floresta Tropical, por ser mais próxima e composta também por Floresta Estacional Semidecidual; (2) características intrínsecas de cada corpo d’água devem exercer maior influência na riqueza e abundância das comunidades de macroalgas do que parâmetros mais gerais de cada fragmento, como forma, tamanho e matriz adjacente, e da ordem de grandeza do riacho e sua respectiva bacia de drenagem. Este trabalho teve como objetivo geral realizar o levantamento florístico e analisar a distribuição ecológica das comunidades de macroalgas lóticas de fragmentos florestais remanescentes de Floresta Estacional Semidecidual da região noroeste do estado de São Paulo (20o00’13”-21o37’14”S, 48o32’26”- 50o26’02”O). Foram amostrados 17 riachos pertencentes a 12 fragmentos, no intervalo de junho a agosto de 2007 e 2008, período mais favorável para a região (estação seca). Foram identificadas 16 espécies de macroalgas, pertencentes a 14 gêneros. A maioria das espécies (69%) foi encontrada em um único ponto. Cyanophyta e Chlorophyta foram os grupos predominantes (44 e 37,5%), seguidos por Rhodophyta (12,5%) e Heterokontophyta (6%). Phormidium retzii (Cyanophyta) foi a espécie mais frequente, ocorrendo em seis pontos de amostragem. Apenas duas espécies representaram novos registros para a região: Trichocoleus sociatus (Cyanophyta) e Vaucheria pseudogeminata (Heterokontophyta); a última representa...
Several studies involving the flora and distribution of lotic macroalgal communities have been carried out in the northwest region of São Paulo State, southeastern Brazil. However, the lotic macroalgae in remnant forest fragments have never been studied, the most relevant aspect of this study. The following hypotheses have been tested: 1) among the biomes/regions previously studied in São Paulo State, the flora of the northwest region is expected to reveal the highest floristic similarity with the Tropical Forest, since it is the nearest biome and also composed by semidecidual seasonal forest; 2) particular characteristics of each water body are expected to be more influential on the species richness and abundance of macroalgal communities than more general parameters of each forest fragment, such as surrounding matrix, stream order and position in the respective drainage basin. This study aimed at surveying the flora and describing the ecological distribution the of lotic macroalgal communities from remnant forest fragments composed of semidecidual seasonal forest in the northwest region of São Paulo State (20o00’13”-21o37’14”S, 48o32’26”-50o26’02”O). 17 streams were sampled in 12 forest fragments from June to August of 2007 and 2008 during the typical most favorable period in the region (dry season). 16 species have been surveyed, belonging to 14 genera. 69% of species were found in a single site. Cyanophyta and Chlorophyta were the predominant algal groups (44 amd 37.5%), followed by Rhodophyta (12.5%) and Heterokontophyta (6%). Phormidium retzii (Cyanophyta) was the most frequent species, occurring in six sampling sites. Only two species were new records for the region: Trichocoleus sociatus (Cyanophyta) and Vaucheria pseudogeminata (Heterokontophyta); the later represents the first report for Brazil. The regional flora was more similar (nine species in common, 56%)... (Complete abstract click electronic access below)

APA, Harvard, Vancouver, ISO und andere Zitierweisen

40

Martins, Ana Margarida Ferreira. „Phycobiliproteins extraction from the red macroalga Gracilaria vermiculophylla“. Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/19031.

Der volle Inhalt der Quelle

Annotation:

Mestrado em Biotecnologia
Recentemente, o interesse pelos produtos obtidos de fontes naturais tem crescido em relação aos produtos sintéticos. Assim sendo, produtos extraídos de fontes naturais têm sido alvo de especial atenção pela indústria e pelo meio académico. Alguns desses compostos interessantes podem ser encontrados nas macroalgas vermelhas, nomeadamente a R-ficoeritrina, uma das ficobiliproteínas mais valiosas presentes na macroalga. Contudo, a maior dificuldade encontrada na extração e purificação desta proteína fotossintética está associada à necessidade de metodologias de extração e purificação mais eficazes, de mais baixo impacto económico e ambiental, capaz de remover as proteínas da biomassa, mantendo a sua estrutura conformacional e principais atividades. Neste trabalho, um conjunto de parâmetros experimentais de extração foram otimizados, nomeadamente o solvente em causa. Várias soluções aquosas de líquidos iónicos foram testadas na extração de ficobiliproteínas a partir da macroalga vermelha Gracilaria vermiculophylla. Depois de otimizado o tempo de extração, a razão sólido-líquido, o solvente, pH e concentração de solvente, foi possível chegar a uma metodologia capaz de extrair mais 30% de ficobiliproteínas quando comparado com o método convencional reportado na literatura.
In the past few years, there has been an increased demand for natural compounds over the synthetic ones. Thus, products extracted from natural sources have gained significant interest among industries and academia. Several of these interesting compounds are present in red macroalgae namely R-phycoerythrin, a phycobiliprotein. However, the major drawback is associated with the demand for more effective, with low economic and environmental impact extraction and purification methodology capable to remove the protein from the biomass, while maintaining its structure conformation and main activities. Therefore, the search for efficient extraction technologies is of utmost importance. In this work, a set of different parameters of extraction was optimized, such as the solvent used. Aqueous solutions of ionic liquids were screened for the phycobiliproteins extraction from the Gracilaria vermiculophylla. Once optimized the time of extraction, the solid-liquid ratio, the solvent, the solvent concentration, and the pH, it was possible to design an efficient methodology capable to enhance the phycobiliproteins extraction in 30% when compared with the conventional extraction methodology.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

41

Azevedo, Vítor Manuel Madureira. „Lipidomic study of the red marine macroalgae as source of bioactive compounds“. Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17513.

Der volle Inhalt der Quelle

Annotation:

Mestrado em Mestre em Bioquímica, ramo da Bioquímica Clínica
Marine macroalgae, or seaweeds, have gained an increased interest in recent times for the use in various biotechnological applications, due to the added-value of their chemical constituents. Among them, glycolipids and phospholipids display several commercial applications in a wide spectrum of industries, such as food, pharmaceutical and cosmetic. In an effort to further understand the lipid composition of macroalgae, the present work reports, for the first time, the isolation and characterization of the polar lipid profile of the red macroalgae Porphyra dioica cultivated on a land-based integrated multi-trophic aquaculture (IMTA) system, using a lipidomic-based approach employing hydrophilic interaction liquid chromatography-eletrospray ionization mass spectrometry (HILIC-ESI-MS). The fatty acid profile of this species of seaweed was also determined, accounting for season variability and its life cycle. The polar lipid profile of P. dioica revealed the presence of over 69 molecular species, corresponding to glycolipids (sulfoquinovolsyldiacylglycerols, sulfoquinovosylmonoacylglycerols, digalactosyldiacylglycerols) and glycerophospholipids (lyso- and phosphatidylglycerols), lyso- and phosphatidylcholines), as well as phytyl derivatives. Some of these polar lipids contain polyunsaturated fatty acids (PUFAs), namely arachidonic acid (C20:4) and eicosapentaenoic acid (C20:5), thus revealing the ability of P. dioica to biosynthesize this long chain PUFAs. P.dioica from the winter season revealed to be richer in PUFA content, accounting for 37.0% of total fatty acid (TFA) content, as opposed to P. dioica from the summer season (25.0% of TFA content). Eicosapentaenoic acid (EPA) content was revealed to be being significantly higher in the winter season (25.2% of TFA content). The diploid sporophyte conchocelis phase of P. dioica showed to possess the highest amount of PUFAs (47.0% of TFA content), with arachidonic acid being the most abundant fatty acid (21.2% of TFA content). Several of the lipids identified have been reported to possess nutritional and health benefits, thus allowing the valorisation of P. dioica from IMTA as a source of bioactive compounds, adequate for the use in a wide range of different applications and as a functional food, rich in omega-3 fatty acids.
As macroalgas têm vindo a ganhar um interesse cada vez maior para o uso em diversas aplicações biotecnológicas, devido ao valor acrescentado dos seus diferentes constituintes. Entre estes, os glicolípidos e os fosfolípidos podem ser usados comercialmente em diferentes indústrias, tais como as indústrias alimentar, farmacêutica e cosmética. Com o objetivo de compreender melhor a composição lipídica das macroalgas, o presente trabalho relata, pela primeira vez, a caracterização do perfil de lípidos polares da macroalga vermelha Porphyra dioica, cultivada num sistema de aquacultura multi-trófica integrada (IMTA), utilizando para esse fim uma abordagem lipidómica baseada na espectrometria de massa (HILIC-ESI-MS). Foi também determinado o perfil de ácidos gordos da referida espécie de alga, tendo em consideração a variabilidade sazonal e o seu ciclo de vida. O perfil de lípidos polares da alga P. dioica revelou a presença de mais de 69 espécies moleculares diferentes, correspondendo a classes de glicolípidos (sulfoquinovosildiacilgliceróis, sulfoquinovosilmonoacilgliceróis e digalactosildiacilgliceróis), fosfolípidos (liso- e fosfatidilglicerol, liso- e fosfatidilcolinas) e derivados fitil. Alguns destes lípidos polares contêm ácidos gordos polinsaturados (PUFAs) na sua composição, nomeadamente o ácido araquidónico (C20:4) e ácido eicosapentaenóico (C20:5), revelando, assim, a capacidade da alga P. dioica em biossintetizar este tipo de ácidos gordos polinsaturados de cadeia longa. Considerando a variação sazonal do conteúdo em ácidos gordos, a P. dioica cultivada no inverno revelou ser mais rica em PUFAs, correspondendo a 37.0% do conteúdo total de ácidos gordos, contrariamente à P. dioica cultivada no verão (25.0%). O conteúdo em ácido eicosapentaenóico (EPA) é significativamente maior na estação de inverno (25.2%). O perfil em ácidos gordos também variou com o ciclo de vida P. dioica, sendo que na fase de conchocelis a quantidade de PUFA é significativamente mais elevada (47.0% de conteúdo de ácidos gordos), sendo o ácido araquidónico o ácido gordo mais abundante (21.2% de conteúdo de ácidos gordos).Várias classes de lípidos polares foram identificados como possuindo benefícios nutricionais e para a saúde, permitindo assim a valorização da alga vermelha P. dioica produzida em IMTA como uma fonte de compostos bioativos, adequados para o uso numa grande variedade de aplicações como um alimento funcional, rica em ácidos gordos polinsaturados ómega-3.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

42

Marshall, Rhoda A. „Halocarbon production by red macroalgae (Rhodophyta)“. Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326295.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

43

Medeiros, Amanda da Silva. „Diversidade de macroalgas da Baía do Almirantado, ilha Rei George, Península Antártica, baseada em 'DNA barcoding' e outros marcadores moleculares“. Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-24032014-090801/.

Der volle Inhalt der Quelle

Annotation:

Baseado em estudos morfológicos, as macroalgas marinhas da Baía do Almirantado (Ilha Rei George, Península Antártica) estão representadas por 55 táxons, sendo 30 Rhodophyta, 16 Phaeophyceae e 9 Chlorophyta. Recentemente foi proposta a utilização de 'DNA barcode' para uma rápida e acurada identificação de espécies de macroalgas. Sendo a região 5\' do gene mitocondrial cox 1utilizado para identificação de algas vermelhas e pardas; o gene plastidial tufA utilizado na identificação de algas verdes; e o domínio V do gene 23S rRNA - UPA, universal plastid amplicon, utilizado na identificação de organismos fotossintetizantes. O objetivo desse trabalho foi obter sequências do tipo 'DNA barcodes' e de outros marcadores filogenéticos para a formação do primeiro banco de dados moleculares para as macroalgas da Baía do Almirantado, Antártica. Cerca de 100 espécimes de macroalgas foram coletados, em diversos pontos da baía, durante as OPERANTARes XXV e XXIX, que ocorreram durante dezembro de 2006 a junho de 2007 e dezembro de 2010 a janeiro de 2011, respectivamente. No presente trabalho, foi obtido um total de 209 sequências, cobrindo 29 espécies das 55 citadas para o local, sendo que 157 sequências são para marcadores moleculares do tipo 'DNA barcode', das quais 95 sequências são para o marcador do cloroplasto UPA, 39 sequências para o marcador mitocondrial cox1 e 23 sequências para o tufA. As sequências consenso dos 'DNA barcodes' foram submetidas à análise de distância para determinar os agrupamentos genéticos. Após a análise dos agrupamentos obtidos para os 'DNA barcodes', foram selecionados espécimes, representando cada táxon, para o sequenciamento dos marcadores filogenéticos rbcL, SSU ou ITS totalizando 52 sequências. Neste estudo, foram obtidos dados moleculares para 8 espécies de Chlorophyta, 9 espécies de Phaeophyceae e 14 espécies de Rhodophyta. Entre as espécies de Chlorophyta, Prasiola sp. e Protomonostroma rosulatum (citada anteriormente como P. undulatum), de Phaeophyceae Chordaria linearis e as Rhodophyta Acanthococcus antarticus, Plumariopsis peninsularis e Callophyllis sp. (citada anteriormente como Callophyllis atrosanguinea) são novas citações para a Baía do Almirantado. Sendo que a espécie Callophyllis sp. é possivelmente uma nova espécie. Outras duas espécies previamente citadas, baseado nos resultados moleculares, não ocorrem no local, Desmarestia chordalis e Pyropia woolhousiae. Com os resultados obtidos neste trabalho o número de espécies que ocorrem na Baía do Almirantado passa a 57 táxons
Based on morphological studies, the marine macroalgae of Admiralty Bay ( King George Island , Antarctic Peninsula ) are represented by 55 taxa: 30 Rhodophyta, 16 Phaeophyceae and 9 Chlorophyta. It was recently proposed the use of DNA barcodes for quick and accurate identification of seaweeds. The 5\' end region of mitochondrial cox1 gene is used to identify brown and red algae, the plastid gene tufA is used in identifying green algae, and the V domain of the 23S rRNA gene - UPA universal plastid amplicon is used to identify photosynthetic organisms in general. The aim of this study was to obtain sequences of DNA barcodes and other phylogenetic markers for the formation of the first molecular database for macroalgae of Admiralty Bay, Antarctica. About 100 specimens of macroalgae were collected at various points of the bay during the OPERANTARs XXV and XXIX , which occurred during December 2006 to June 2007 and December 2010 and January 2011 respectively. In this study, we obtained a total of 209 sequences, covering 29 of the 55 species cited for the site. Of those 157 sequences are DNA barcodes, of which 95 are for the marker sequences of chloroplast UPA, 39 sequences for the mitochondrial markercox1 and 23 sequences for the tufA. The consensus sequences of the DNA barcodes were subjected to distance analysis to determine the genetic groupings.After analyzing the clusters obtained for the DNA barcodes, specimens representing each taxon were selected to the sequencing of phylogenetic markers rbcL, SSU and/or ITS sequences totaling 52 sequences for those markers. In this study, molecular data were obtained for 8 species of Chlorophyta , 9 species of Phaeophyceae and 14 species of Rhodophyta. Among the Chlorophyta species, Prasiola sp. and Protomonostroma rosulatum> (previously cited as P. undulatum), the Phaeophyceae Chordaria linearis and the Rhodophyta Acanthococcus antarticus, Plumariopsis peninsularis and Callophyllis sp. (previously cited as Callophyllis atrosanguinea) are new records for the Admiralty Bay. And the species Callophyllis sp. is possibly a new species. Other two species previously mentioned, based on molecular results, Desmarestia chordalis and Pyropia woolhousiae do not occur at the site. With the results obtained in this work the number of species that occur in Admiralty Bay are of 57 taxa.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

44

Mellor, A. „The uptake of metals by marine macroalgae“. Thesis, Queen's University Belfast, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268333.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

45

Evans, Oliver Graham Evans. „Modeling the Light Field in Macroalgae Aquaculture“. University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1542810712432336.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

46

Marques, Luiza Grecco e. „Aminoácidos tipo micosporina: novas metodologias e distribuição em macroalgas da costa brasileira“. Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-20072015-155636/.

Der volle Inhalt der Quelle

Annotation:

A radiação ultravioleta (RUV) causa efeitos deletérios em ecossistemas aquáticos e terrestres. Um dos mecanismos de defesa criados pelos organismos para evitar estes danos é o acúmulo de compostos que absorvem RUV, dentre os quais os aminoácidos tipo micosporina (MAAs, do inglês mycosporine-like amino acids) representam uma classe importante. As MAAs são substâncias solúveis em água caracterizadas pela presença de uma unidade ciclo-hexenona ou ciclo-hexenimina conjugada com nitrogênio substituído por um aminoácido, aminoálcool ou grupo amino, apresentando absorção máxima entre 308 e 362 nm e altos coeficientes de absortividade molar. Dado o importante papel desempenhado pelas MAAs na fisiologia e bioquímica celular de algas, seja atuando como protetoras de RUV ou como antioxidantes, o objetivo desta tese foi expandir o corpo de conhecimentos disponíveis sobre a ocorrência e distribuição destes compostos em macroalgas brasileiras. Para atingir tal meta, foi necessário desenvolver procedimentos analíticos de isolamento por cromatografia líquida de alta eficiência (high procedure liquid chromatography, HPLC), de modo a gerar padrões que pudessem ser utilizados para a qualificação e quantificação de MAAs em extratos de algas. Foi necessário também desenvolver dois novos métodos de análise por HPLC acoplada a espectrometria de massas (HPLC-MS) - sendo um utilizado como método diagnóstico, capaz de indicar se há MAAs presentes em determinada amostra, e outro utilizado como método para quantificação. Todos os métodos trouxeram bons resultados, e os métodos por HPLC-MS foram utilizados para o estudo de diversas macroalgas coletadas na região intertidal de praias do litoral Sul do estado do Espírito Santo - Brasil. Apesar da localização restrita, é o maior estudo desta natureza realizado até então com algas do litoral brasileiro. Além disso, 11 dos 32 gêneros e 34 das 45 espécies presentes nesta tese nunca haviam sido alvo de nenhum estudo relacionado a MAAs. Nessas amostras, foi possível encontrar oito MAAs: chinorina, palitina, porphyra-334, asterina-330, palitinol, micosporina-2-glicina, o par cis/trans usujireno/paliteno e uma molécula desconhecida com relação massa-carga de 317 m/z ([M+H]+). Dentre elas, as três primeiras foram quantificadas de forma absoluta, e pôde-se perceber que as rodófitas apresentam níveis de MAAs sensivelmente maiores que as clorófitas e feófitas. Em relação à variedade, foi possível notar que, dentre as amostras que possuem dados do conteúdo de MAAs na literatura (seja para a espécie ou para o gênero), praticamente todas apresentam maior variedade de MAAs do que o anteriormente descrito. Foi encontrada a maior variedade de MAAs já descrita para uma alga parda: seis MAAs diferentes nas espécies Dictyopteris delicatula e Padina gymnospora coletadas na praia de Castelhanos - ES. Pôde-se detectar, pela primeira vez, a presença de MAAs em 32 espécies de macroalgas. Algumas espécies mostram-se fontes muito interessantes de MAAs para diferentes usos pela indústria, seja para a obtenção de compostos puros ou para a utilização de seus extratos como ingredientes de formulações de filtros solares. A molécula desconhecida, cujo íon quasimolecular [M+H]+ apresenta m/z 317, foi tentativamente identificada como sendo a micosporina-glicina-alanina. Este é o primeiro trabalho a descrever a ocorrência desta molécula in natura.
Ultraviolet radiation (UVR) exerts deleterious effects on aquatic and terrestrial ecosystems. One defense mechanism created by organisms to avoid this damage is the accumulation of UV-absorbing compounds, among which the mycosporine-like amino acids (MAAs) represent an important class. MAAs are water-soluble compounds characterized by the presence of a cyclohexenone or cyclohexenimine ring conjugated with amino acids, amino alcohols or other amino groups, presenting absorption maxima ranging from 309 nm to 362 nm and high molar extinction coefficients. Given their important role in algae physiology and cellular biochemistry, as photoprotective compounds or antioxidants, the objective of this thesis is to expand the available knowledge on the occurrence and distribution of MAAs in Brazilian macroalgae. To achieve this goal, it was necessary to develop an isolation methodology by high procedure liquid chromatography (HPLC), so as to generate standards for qualifying and quantifying MAAs in macroalgae extracts. It was also necessary to develop two new analysis methods by HPLC coupled to mass spectrometry (HPLC-MS) - one utilized as a diagnosis method, capable of indicating if there are MAAs in a given sample; and the other utilized as quantification method. All methods gave good results, and the ones relying on HPLC-MS were used to study several macroalgae collected at the intertidal region of beaches located in the south coast of Espírito Santo State - Brazil. This is the biggest study of this nature ever done with Brazilian macroalgae; besides that, 11 out of 32 genera and 34 out of 45 species herein tested had never had their content of MAA assessed. In these samples, it was possible to find eight MAAs: shinorine, palythine, porphyra- 334, asterina-330, palythinol, mycosporine-2-glycine, the cis/trans pair usujirene/palythene and an unknown molecule with mass-to-charge ratio of 317 m/z ([M+H]+). Among them, absolute quantification was performed for the first three ones, and it was possible to notice that red algae have higher MAA levels than green and brown algae. In terms of variety, it could be seen that, amongst the samples that have MAA data available in the literature (either for the species or for the genus), nearly all present a higher MAA variety than the previously described one. The highest variety ever recorded from brown algae is presented in this work: six different MAAs in Dictyopteris delicatula and Padina gymnospora, both collected at Castelhanos Beach - ES. For the first time, it was possible to detect MAAs in 32 species of macroalgae. Some species seem to be very interesting sources of MAAs for industrial purposes, either for obtaining pure compounds or for utilizing their extracts as ingredients of sunscreen formulas. The unknown molecule, with mass-to-charge ratio of 317 m/z ([M+H]+), was tentatively identified as mycosporine-glycine-alanine. This is the first work to describe the occurrence of this molecule in natura.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

47

Gaubert, Julie. „Caractérisation et sources de variation du métabolome : le cas de l’algue brune Lobophora des écosystèmes coralliens de Nouvelle-Calédonie“. Electronic Thesis or Diss., Sorbonne université, 2018. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2018SORUS530.pdf.

Der volle Inhalt der Quelle

Annotation:

Les macroalgues marines constituent un riche réservoir de composés, aussi appelés métabolites spécialisés, qui jouent diverses fonctions écologiques et font partie des traits adaptatifs. Leur concentration peut varier en fonction de facteurs biotiques et abiotiques mais peu d’études sur les réponses globales des métabolites (métabolome) sont disponibles. C’est dans ce contexte que s’inscrit cette étude doctorale centrée sur les sources potentielles de variations du métabolome chez une algue brune commune des récifs coralliens, Lobophora. Pour cela, quatre espèces de Lobophora présentant des morphologies et des habitats variés ont été sélectionnées dans le lagon de Nouvelle-Calédonie. Nous avons dans un premier temps cherché à caractériser et identifier des métabolites via des approches de chimie traditionnelle. Les lobophorénols, précédemment identifiés chez L. rosacea, ont été retrouvés chez cette espèce ainsi que des molécules polyoléfines chez toutes les espèces étudiées. Plusieurs tests de bioactivité sur diverses souches biologiques ont été mis en place sur des fractions algales dans une visée de valorisation et des résultats positifs ont été obtenus lors du criblage antibactérien contre Staphylococcus aureus. Dans un deuxième temps, les sources de variations du métabolome ont été étudiées à plusieurs échelles par des approches de métabolomique non ciblée. Il ressort de ces diverses études que le métabolome de Lobophora est hyper-variable. Les espèces présentent une empreinte métabolomique propre, sans variation intra-thalle. Leur métabolome varie à l’échelle spatiale, en fonction des sites d’étude et des habitats testés, et au cours du temps en lien avec les facteurs environnementaux, tels que température et salinité. En outre, des conditions de faible pH entraînent également des changements métabolomiques comme nous avons pu le tester en conditions naturelles (site de Bouraké) et en conditions contrôlées. Parmi les marqueurs chimiques liés à ces conditions changeantes nous avons identifié les lobophorénols et plusieurs de leurs potentiels dérivés, des dérivés d’acides gras oxygénés polyinsaturés et des composés polyoléfines. Bien que la métabolomique ait été appliquée avec succès pour discriminer les espèces ou détecter l’effet d’un stress environnemental, les présents travaux ont également souligné la difficulté à travailler sur le genre Lobophora, riche en graisses et pigments, et la limitation dans l’annotation des marqueurs en raison du peu de références disponibles pour ce groupe d’organismes marins encore peu étudiés via cette approche
Marine macroalgae represent a rich source of compounds, also known as specialized metabolites that play diverse ecological functions and are part of adaptive traits. Their concentration can vary according to biotic and abiotic factors but just a few studies on the overall responses of metabolites (metabolome) are available. In this context, the present doctoral study focuses on the potential sources of metabolomic variations in a common coral reef‘s brown alga, Lobophora. To this end, four Lobophora species with various morphologies and habitats have been selected within the New Caledonian lagoon. We first sought to characterize and identify metabolites via traditional chemical approaches. Lobophorenols, previously identified in L. rosacea, were found in this species as well as polyolefin molecules in all studied species. Several bioactivity tests on various biological targets have been set up on algal fractions in a valorization goal and positive results were obtained during antibacterial screening against Staphylococcus aureus. In a second step, the sources of metabolomic variations were studied at several scales by non-targeted metabolomics approaches. These various studies showed that the metabolome of Lobophora is highly variable. The species have their own metabolomic fingerprinting, without intra-thallus variation. Their metabolome varies spatially, depending on the study sites and tested habitats, and over time in relation to environmental factors, such as temperature and salinity. In addition, low pH conditions also lead to metabolomic changes, both in natural conditions (Bouraké site) and under controlled conditions. Among the chemomarkers linked to these changing conditions, we identified lobophorenols as well as several of their potential derivatives, some oxygenated polyunsaturated fatty acid derivatives and polyolefin compounds. Although metabolomics has been successfully applied to discriminate species or to detect the effect of environmental stress, the present work also highlighted the difficulty of working on Lobophora genus, rich in fats and pigments, and the limitation in markers annotation due to the lack of available references for this group of marine organisms still under-researched using this approach

APA, Harvard, Vancouver, ISO und andere Zitierweisen

48

Nunes, da Silva Ramos Filipe José. „Identification of Suitable Areas for Offshore Macroalgae Cultivation“. Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-243911.

Der volle Inhalt der Quelle

Annotation:

Research in sustainable macroalgae aquaculture has been gaining hype (e.g. Seafarm) to provide advancements in new significant sources of food, feed, materials and bio-energy. Despite the fact that in Asia the offshore production of macroalgae is established for many decades, in Europe is still in its infancy. The issue on where to find suitable cultivation areas without conflicting with current uses to respect the environment and the socio-economic activities is a great challenge. This Master of Science thesis aimed to find suitable offshore areas in order to facilitate implementations of macroalgae cultivations in the Swedish West Coast. Thirteen criteria in environmental, economic and social sustainability aspects were identified and employed (e.g. Depth, Distance to Ports, and Natural and Preserved areas (NPAs)), and the tools Geographic Information Systems (GIS) and Multi-criteria Analysis (MCA) were used in the form of GIS-MCDA, an integrated method available in Idrisi. To aggregate the criteria, Boolean and Weighted Linear Combination (WLC) techniques were applied. The results showed that Boolean areas cover 537 km2 (6,98% of the study area). The best suitable areas, possessing the maximum suitability index 10, that resulted from two WLC models comprise 5 km2 (0,07% of the study area) and 26 km2 (0,34% of the study area) including and excluding the criterion NPAs as constraint, respectively. The results further indicated that GIS-MCDA models excelled in providing an overview for effective spatial decision-making. Both techniques play a role in suitability analysis and complement each other in finding an optimal site which could be carefully selected out of the identified areas. It is recommended that areas with a suitability index 10 be chosen inside Boolean suitable areas. Moreover, this study could act as a driving force to build a resilient planning framework that would boost sustainable placement and development of offshore macroalgae cultivations.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

49

Myhrum, Sletmoen Ingeborg, und Matilda Carlsson. „Optimization of a biogas plant with macroalgae, Grenada“. Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-281695.

Der volle Inhalt der Quelle

Annotation:

For several years, blooming of algae around the Caribbean islands, including Grenada, has been an issue. This influenced AlgaeFuel Technology into looking at the possibility of biogas production with macroalgal biomass in Grenada. Grenada is dependent on fossil fuels to meet its energy needs. Using the algae for producing biogas could possibly decrease greenhouse gas emissions. There are different factors affecting the production of biogas and therefore, the purpose of this project is to optimize a biogas plant with the use of macroalgal biomass, with focus in Grenada. A literature review was made to gain more knowledge about biogas production through anaerobic digestion, particularly by using macroalgae as biomass. An experiment was made through building four biogas plants in mini format with guidelines from the Swedish University of Agriculture Science. Each plant was fed with different combination of biomass to be compared in biogas production. The result from the experiment gave no clear differences in biogas production which most likely was due to errors during the experiment. Optimizing of a biogas plant includes several aspects. Pretreatment has shown to be an effective way of increasing the methane yield and the biogas production rate. Temperature regulation is significant in order to achieve a more efficient biogas production. The effect of pretreatment and temperature regulation needs to be compared with their energy consumption for a sustainable biogas production. Continues supply of biomass need to be secured which can be done by storing of algae in seasons with abundance and utilization of alternative types of biomass. A combination of biomass through co-digestion is an effective way of increasing the methane yield and also make the biogas plant more efficient in the longer run. In Grenada it is important to prioritize sustainable solutions that can fulfill Grenada’s vision towards 2030, with 100 percent renewable energy. Utilization of macroalgal biomass for biogas production in Grenada can be a solution to both decrease the negative impact of algae bloom and increase the share of renewable energy.
Under flera år har algblomning runt de Karibiska öarna, däribland Grenada, varit ett problem. Detta influerade AlgaeFuel Technology till att se närmare på möjligheterna för biogasproduktion med makroalger som biomassa i Grenada. Grenada är beroende av fossila bränslen för att möta sitt energibehov. Att använda algerna för produktion av biogas kan möjligtvis minska utsläpp av växthusgaser. Det finns olika faktorer som påverkar biogasproduktion och syftet med detta projekt är därför att optimera en biogasanläggning med användning av makroalger som biomassa, med fokus i Grenada. En litteraturstudie gjordes för att få mer kunskaper om biogasproduktion genom syrefri rötning, särskilt med användning av makroalger som biomassa. Ett experiment gjordes genom att bygga fyra biogasanläggningar i miniformat med riktlinjer från Svenska lantbruksuniversitetet. Varje anläggning var matad med fyra olika kombinationer av biomassa för att bli jämförd i produktion av biogas. Resultatet från experimentet gav inga tydliga skillnader i biogasproduktion vilket troligen berodde på felkällor under experimentet. Vid optimering av en biogasanläggning inkluderas flera aspekter. Förbehandling har visat sig att vara ett effektivt sätt att öka utbytet av metan och hastigheten av biogasproduktionen. Temperaturreglering är viktigt för att uppnå en mer effektiv biogasproduktion. Effekten av förbehandling och temperaturreglering behöver jämföras med deras energikonsumtion för att få en hållbar biogasproduktion. En kontinuerlig tillgänglighet av biomassa behövs, vilket kan uppnås genom lagring av alger under säsonger med överflöd samt användning av alternativ biomassa. En kombination av biomassa genom samrötning är ett effektivt sätt att öka metanutbytet och även göra biogasanläggningen mer effektiv i det långa loppet. I Grenada är det viktigt att prioritera hållbara lösningar som kan uppnå deras vision fram mot 2030 med 100 procent förnyelsebar energi. Att använda makroalger som biomassa för biogasproduktion i Grenada kan vara en lösning för att båda minska dom negativa effekterna från algblomning och öka andelen förnyelsebar energi.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

50

França, Lucas Vagueiro de. „Macroalgae as feedstock for cultivation of marine bacteria“. Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14921.

Der volle Inhalt der Quelle

Annotation:

Mestrado em Biotecnologia - Biotecnologia Industrial e Ambiental
Alginate, laminarin and mannitol amount up to 60% of dry weight in brown macroalgae. The presence of alginate and laminarin-degrading enzymes and mannitol metabolic machinery have been confirmed by Matís, a partner in European BlueGenics project. Thus, in a biorefinery perspective, R. marinus can potentially perform the saccharification and fermentation of brown macroalgae carbohydrates to yield commercial valuable biocompounds, as thermostable enzymes and glycosidic carotenoids. Rhodothermus marinus is a moderate thermophilic (65ºC) and slight halophilic (1.0% NaCl) marine bacterium. Therefore, one of the objectives of this project was to decrease the NaCl concentration in the fermentation medium, since chloride leads to a lower equipment lifetime due to stainless steel corrosion of bioreactors. The main objective of this work was the study of the bacterium R. marinus pattern of growth when cultivated in the main brown macroalgal carbohydrates. This work was performed with five R. marinus strains, two of which were successfully acclimatized to cultivation in Medium 166, cryopreserved in glycerol and recultivated in liquid media, being subject of study in the assays with different carbon and sodium sources in shake flask. The growth studies with different carbon sources suggested that (i) strain 5 presented higher glucose consumption and growth, even though none of the strains consumed all the glucose available in the media; (ii) although none of strains consumed mannitol, strain 5 seemed to be more robust to its presence; and (iii) the growth differences between the controls and the assays with alginate and pretreated alginate were not significant enough to infer if any alginate consumption occurred. It was tested a partial and total substitution of NaCl by Na2SO4. The process was not successful, since Na2SO4 seem to represent a stress factor to both R. marinus strains. Interestingly, the strain 5, when cultivated in Medium 166 containing only a half of NaCl standard concentration, presented a similar growth pattern to control. In the operational conditions imposed in shake flask cultivations containing two tested brown macroalgae (orginial and pretreated) as feedstock for growth, mannitol was not consumed. It was not possible to monitor the alginate and laminarin saccharification and fermentation. Although, the results showed that brown macroalgae are a potential feedstock under the biorefinery concept, since some R. marinus growth was observed. The more promising result to BlueGenics project was obtained from shake flask cultivations of strain 5 in Medium 166 with 0.500% NaCl and 10.0 g.L-1 glucose, since the growth with low chloride content determinates the feasibility of the scale-up of the process to bioreactor . Because of that, the assay was validated in 3L controlled bioreactor. The process presented a μmax of 0.208 h-1, a maximum biomass concentration of 8.75 gX.L-1, a volumetric biomass production rate of 0.295 g.L-1.h-1 and a volumetric glucose uptake rate of 0.293 g.L-1.h-1. Some feeding strategies were tested but further assays have to be performed in order to optimize the bioprocess.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Dissertationen zum Thema „Macroalgue“

Geben Sie eine Quelle nach APA, MLA, Chicago, Harvard und anderen Zitierweisen an