Academic literature on the topic 'Phaeophycae'
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Journal articles on the topic "Phaeophycae"
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Pribadi, Tri Dewi Kusumaningrum, and Yudi Nurul Ihsan. "Carbon Content In Macroalgae Species Against Temperature Regime." Omni-Akuatika 15, no. 2 (October 10, 2019): 1. http://dx.doi.org/10.20884/1.oa.2019.15.2.727.
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Temperature rise due to climate change have an impact on various ecosystems, including coastal ecosystems. Temperature rise also affects plant metabolism, such as carbon uptake. Macroalgae is the dominant community in the intertidal zone, and potential to absorb carbon. A series of experiments on several dominant macroalgae species from the south coast of West Java have been done to see the effect of temperature regime on carbon content. The treatment of temperatures of 24, 27, 30, and 33 °C was carried out for 72 hours against 6 macroalgae species representing Chlorophycae, Phaeophycea and Rhodophyceae to investigate carbon content. The results showed that the macroalgae of Phaeophyceae division showed higher carbon content in comparison to the macroalgae of the other divisions. The temperature that significantly affects chloropyll was 33 oC against all the species being tested.
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Liang, Yanshuo, Han-Gil Choi, Shuangshuang Zhang, Zi-Min Hu, and Delin Duan. "The organellar genomes of Silvetia siliquosa (Fucales, Phaeophyceae) and comparative analyses of the brown algae." PLOS ONE 17, no. 6 (June 16, 2022): e0269631. http://dx.doi.org/10.1371/journal.pone.0269631.
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The brown alga Silvetia siliquosa (Tseng et Chang) Serrão, Cho, Boo & Brawly is endemic to the Yellow-Bohai Sea and southwestern Korea. It is increasingly endangered due to habitat loss and excessive collection. Here, we sequenced the mitochondrial (mt) and chloroplast (cp) genomes of S. siliquosa. De novo assembly showed that the mt-genome was 36,036 bp in length, including 38 protein-coding genes (PCGs), 26 tRNAs, and 3 rRNAs, and the cp-genome was 124,991 bp in length, containing 139 PCGs, 28 tRNAs, and 6 rRNAs. Gene composition, gene number, and gene order of the mt-genome and cp-genome were very similar to those of other species in Fucales. Phylogenetic analysis revealed a close genetic relationship between S. siliquosa and F. vesiculosus, which diverged approximately 8 Mya (5.7–11.0 Mya), corresponding to the Late Miocene (5.3–11.6 Ma). The synonymous substitution rate of mitochondrial genes of phaeophycean species was 1.4 times higher than that of chloroplast genes, but the cp-genomes were more structurally variable than the mt-genomes, with numerous gene losses and rearrangements among the different orders in Phaeophyceae. This study reports the mt- and cp-genomes of the endangered S. siliquosa and improves our understanding of its phylogenetic position in Phaeophyceae and of organellar genomic evolution in brown algae.
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de Ruyter van Steveninck, ED. "Deep water vegetations of Lobophora variegata (Phaeophycae) in the coral reef of Curagao: population dynamics in relation to mass mortality of the sea urchin Diadema antillarum." Marine Ecology Progress Series 36 (1987): 81–90. http://dx.doi.org/10.3354/meps036081.
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Pena Martín, Carolina, Amelia Gómez Garreta, and Manuel B. Crespo. "Sobre la presencia de Dictyota mediterranea (Schiffner) G. Furnari (Dictyotales, Phaeophyceae) en la Península Ibérica." Acta Botanica Malacitana 29 (December 1, 2004): 255–60. http://dx.doi.org/10.24310/abm.v29i0.7234.
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On the presence of Dictyota mediterranea (Schiffner) G. Furnari (Dictyotales, Phaeophyceae) in the Iberian Peninsula.Palabras clave. Dictyota mediterranea, Dictyotales, Phaeophyceae, algas marinas, corología, anatomía.Key words. Dictyota mediterranea, Dictyotales, Phaeophyceae, marine algae, chorology, anatomy.
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Jelic Mrcelic, Gorana, Merica Sliskovic, and Boris Antolic. "Macroalgae fouling community as quality element for the evaluation of the ecological status in Vela Luka Bay, Croatia." Acta Societatis Botanicorum Poloniae 81, no. 3 (2012): 159–65. http://dx.doi.org/10.5586/asbp.2012.028.
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One year qualitative and quantitative study of communities of three major taxonomic groups has been carried out at test panles placed in the upper infarlittoral zone of coastal area of Vela Luka Bay, Croatia. A list of 44 taxa was recorded. <em>Chaetomorpha </em>sp., <em>Ulva </em>sp., <em>Fosliella farinosa</em>, <em>Sphacelaria cirrosa</em>, <em>Polysiphonia scopulorum </em>were the most frequent dominant taxa. Among 27 algal taxa with noticeable presence only three were classified as ESG (Ecological State Groups) I. Low diversity and species richness together with massive presence of the green algae (as <em>Ulva </em>sp.) and negligible presence of ESG I taxa, may lead to erroneous conclusion that Vela Luka Bay is eutrophicated area. Low values of biomass and <em>R/P </em>(Rhodophyceae by Phaeophyceae ratio) Index together with dominance of Phaeophyta also support conclusion that there is no negative impact of nutrient enrichment on macrophyta fouling community in Vela Luka Bay.
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Riadi, Hassane, and Mohamed Kallaz. "Inventaire bibliographique des algues benthiques du littoral marocain. I. Chlorophyceae et Phaeophyceae." Acta Botanica Malacitana 23 (December 1, 1998): 23–41. http://dx.doi.org/10.24310/abm.v23i0.8548.
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L'inventaire bibliographique des Chlorophyceae et Phaeophyceae marines benthiques du littoral marocain a révélé 213 espéces dont 93 Chlorophyceae (6 ordres, 15 familles et 31 genres) et 110 Phaeophyceae (11ordres, 20 familles et 50 genres).
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Flores-Moya, Antonio, Juan Soto, Alberto Sánchez, María Altamirano, Gracia Reyes, and Francisco Conde. "Catálogo de las Phaeophyceae de Andalucía (S. España)." Acta Botanica Malacitana 20 (December 1, 1995): 5–18. http://dx.doi.org/10.24310/abm.v20i.8804.
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Catálogo de las Phaeophyceae de Andalucía (S. España). Se presenta el listado de las Phaeophyceae de las costas andaluzas a partir de datos bibliográficos (desde 1807 hasta 1995). Los taxa se desglosan por provincias. El catálogo contiene 108 especies y taxa infraespecíficos.
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Suryandari, Retno. "Checklist of Macroalgae at Krakal and Drini Beach, Gunungkidul." Proceeding International Conference on Science and Engineering 1 (October 31, 2017): 31–38. http://dx.doi.org/10.14421/icse.v1.266.
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Macroalgae are multicellular plants that do not produce seeds or flowers. All macroalgae are multicellular and do not have a specialized body structure and do not have reproductive mechanism like terrestrial plants. Macroalgae is divided into 3 groups namely Chlorophyta (green algae), Rhodophyta (red algae), and Phaeophyceae (brown algae). Green algae and red algae belong to the Plantae kingdom with green algae (Chlorophyta) and included in the Subkingdom Viridiplantae and red algae (Rhodophyta) into the Biliphyta subkingdom. Brown algae (Phaeophyta) belong to the Chromista kingdom. Based on the research, macroalgae found in Drini and Krakal Gunungkidul are green algae, red algae and brown algae. Green algae found and identified are Anadyomene plicata C. Agardh, Chaetomorpha antennina (Bory) Kṻtzing, Chaetomorpha linum (O.F. Mṻller) Kṻtzing, Boergesenia forbesii (Hardvey) Feldmann, Cladophoropsis herpestica (Montagne) M. Howe, Boodlea composita (Harvey) F. Brand, Caulerpa peltata J.V. Lamoroux, Enteromorpha intestinalis (Linnaeus) Nees, Ulva lactuca Linnaeus. Red algae species found and successfully identified are Acrocystis nana Zanardini, Acanthophora spicifera (M. Vahl) Børgesen, Laurencia papilosa (C. Agardh) Greville, Actinotrichia fragilis (Forsskål) Børgesen, Galaxaura rugosa (J. Ellis & Solander) J.V. Lamoroux, Amphiora anceps (Lamark) Decaisne, Gelidiela acerosa (Forsskål) Feldmann & Hamel, Gracilaria canaliculata Sonder, Gelidiopsis intricata (C.Agardh) Vickers. Brown algae species found and identified are Lobophora variegata (J.V.Lamouroux) Womersley ex E.C.Oliveira, Padina minor Yamada, Sargassum crassifolium J. Agardh, Turbinaria ornata (Turner) J. Agardh. The species that classified as a new record in Indonesia are Cladophoropsis herpestica (Montagne) M. Howe and Gracilaria spinulosa (Okamura) Chang & B.M.Xia.
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Novianty, Hilda, Emienour Muzalina Mustafa, and Suratno Suratno. "Heavy Metals Content in Phaeophyceae from Malang Rapat Waters, Bintan." ILMU KELAUTAN: Indonesian Journal of Marine Sciences 26, no. 1 (February 15, 2021): 57–62. http://dx.doi.org/10.14710/ik.ijms.26.1.57-62.
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The use of brown-macroalgae (Phaeophyceae) as an alginate source is very broad, covering the food and non-food industry, because of that it is necessary to know the safety of these natural resources, one of which is safe from heavy metal contamination. The purpose of this study was to determine heavy metals concentrations accumulated in several types of Phaeophyceae (brown macroalgae) as an alginate source from Malang Rapat waters, Bintan. The method used was descriptive non-experimental. The determination of the location of sampling was done by purposive sampling method. Samples were taken through free collection, identified species and measured of metal contamination concentrations for As, Cd, and Pb. The data obtained were analyzed descriptively. The results showed that Phaeophyceae found in Malang Rapat waters were Turbinaria conoides, Sargassum aquifolium, Padina australis, Hormophysa cuneiformis with each metal concentration contamination of As 13.95 to 23.30 µg.g-1 dry weight; Cd from 0.33 to 1.08 µg.g-1 dry weight and Pb from 4.72 to 9.92 µg.g-1 dry weight. This study showed that all metal contamination ranges in all Phaeophyceae were on the verge of the maximum limit set by the National Standardization Agency of Indonesia Indonesian (SNI) No 7387 of 2009 and National Agency of Drug and Food Control of RI (BPOM) Regulation No 5 of 2018 for dried macroalgae product so that Phaeophyceae from Malang Rapat waters - Bintan was not safe to be used as raw material for alginate source or other processed products of brown-macroalgae.
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Ouriques, Luciane C., and Zenilda L. Bouzon. "Organização estrutural e ultra-estrutural das células vegetativas e da estrutura plurilocular de Hincksia mitchelliae (Harvey) P. C. Silva (Ectocarpales, Phaeophyceae)." Rodriguésia 59, no. 4 (October 2008): 673–85. http://dx.doi.org/10.1590/2175-7860200859404.
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RESUMO O presente estudo tem por objetivo contribuir para o estudo de caracteres sub-celulares que poderão ser utilizados na taxonomia das Phaeophyceae filamentosas, fornecendo dados sobre a estrutura e ultra-estrutura das células vegetativas e do estágio reprodutivo plurilocular de H. mitchelliae. Para tanto, estudos de microscopia de luz e eletrônica de transmissão foram realizados. As células vegetativas e reprodutivas de H. mitchelliae são uninucleadas, revestidas por uma parede celulósica, outros polissacarídeos e proteínas. A presença de um núcleo por célula, a organização dos tilacóides nos cloroplastos, formando bandas com três tilacóides, dispostos longitudinalmente ao eixo maior da organela e ausência de tilacóide no pirenóide foram similares a outras Phaeophyceae. H. mitchelliae também exibiu características ultra-estruturais que estão geralmente associadas a outras espécies, de ordens menos avançadas de Phaeophyceae como a presença de um proeminente pirenóide, dictiossomos perinucleares e plasmodesmos. A morfologia e a organização dos cloroplastos, bem como a presença ou ausência de pirenóide são características importantes dentro das Phaeophyceae. A formação de um novo pirenóide, em estágio de diferenciação, foi observada nos cloroplastos das células vegetativas. Ambas as células apresentaram núcleo com um grande nucléolo, sugerindo uma alta atividade metabólica. Muitos corpos osmiofílicos, os fisóides, foram vistos no citoplasma das células vegetativas e reprodutivas. As células da estrutura plurilocular madura de H. mitchelliae diferiram das células vegetativas por apresentar tamanho reduzido, citoplasma denso e desprovidas de vacúolos.
Dissertations / Theses on the topic "Phaeophycae"
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Reynes, Lauric. "Connectivité et structure génétiques des populations d'Ericaria Zosteroides (Fucales) et Laminaria rodriguezii (Laminariales) des côtes françaises." Electronic Thesis or Diss., Aix-Marseille, 2021. http://www.theses.fr/2021AIXM0205.
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Les forêts d’algues brunes (Phaeophyceae) sont soumises à des combinaisons de pressions d’origine anthropique. Le devenir de ces écosystèmes dépendra de la capacité des populations de ces espèces à évoluer dans cet environnement changeant. A travers ma thèse, j’ai étudié les facteurs susceptibles de contrôler la diversité génétiques des forêts marines en me focalisant sur deux espèces endémiques du bassin méditerranéen, la Fucales Ericaria zosteroides et le kelp des milieux profonds Laminaria rodriguezii. Dans une première partie, je me suis intéressé à la connectivité des populations par une méthode de séquençage partiel du génome (RAD-seq). L’analyse de la structure génétique indique une connectivité réduite, que ce soit pour les populations de E. zosteroides ou L. rodriguezii. En couplant structure génétique et modélisation des courants marins, j’ai étudié la dispersion des propagules en prenant comme cas d’étude, les populations de E. zosteroides en Provence. Les résultats obtenus montrent que la structure génétique est davantage prédite par les courants marins que par l’isolement spatial. Dans une deuxième partie, je me suis intéressé au mode de reproduction de L. rodriguezii, cette espèce étant l’une des rares du genre Laminaria à se reproduire par reproduction végétative et sexuée. Les résultats obtenus confirment l’impact de la clonalité sur la diversité génomique de L. rodriguezii, avec des niveaux variables selon les populations. Outre les questionnements fondamentaux soulevés par ces résultats, l’existence d’une forte structure génétique à courte distance pour des populations éparses, a des implications importantes pour la conservation de ces espècesMarine forests of brown algae (Phaeophyceae) are impacted by a combination of anthropic pressures. The fate of these ecosystems will depend on the adaptive abilities of populations facing this changing environment. Through my PhD, I studied the factors likely to control the genetic diversity of marine forests by focusing on two endemic species of the mediterranean basin, the Fucoid Ericaria zosteroides and the deep-sea kelp Laminaria rodriguezii. In the first part, I studied the connectivity of populations by a method of reduced representation sequencing of genomes (RAD-seq). The analysis of the genetic structure indicates a reduced connectivity for both E. zosteroides and L. rodriguezii populations. By coupling genetic structure and modeling of marine currents, I studied the role of propagules dispersal, taking as a study case, the populations of E. zosteroides in Provence. The results indicate that the genetic structure is predicted by ocean currents rather than spatial isolation. In the second part, I studied the mode of reproduction of the kelp L. rodriguezii, this species being one of the few of the genus Laminaria to reproduce by vegetative and sexual reproduction. The results obtained indicate an impact of clonality on the genomic diversity of L. rodriguezii, with contrasting levels depending on the populations. In addition to the fundamental questions raised by these results, the existence of a strong genetic structure at short distances for populations divided into habitat patches has important implications for the conservation of these species
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Heesch, Svenja, and n/a. "Endophytic phaeophyceae from New Zealand." University of Otago. Department of Botany, 2005. http://adt.otago.ac.nz./public/adt-NZDU20060901.141241.
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The aims of this study were to find endophytic brown algae in marine macroalgae from New Zealand, isolate them into culture and identify them using morphological as well as molecular markers, to study the prevalence of pigmented endophytes in a representative host-endophyte relationship, and to reveal the ultrastructure of the interface between the obligate parasite Herpodiscus durvillaeae (LINDAUER) SOUTH and its host Durvillaea antarctica (CHAMISSO) HARRIOT.
Three species of pigmented endophytic Phaeophyceae were isolated from New Zealand macrophytes. They were distinguished based on morphological characters in culture, in combination with their distribution among different host species and symptoms associated with the infection of hosts. ITS1 nrDNA sequences confirmed the identity of two of the species as Laminariocolax macrocystis (PETERS) PETERS in BURKHARDT & PETERS and Microspongium tenuissimum (HAUCK) PETERS. A new genus and species, Xiphophorocolax aotearoae gen. et sp. ined., is suggested for the third group of endophytic Phaeophyceae. Three genetic varieties of L. macrocystis as well as two varieties each of M. tenuissimum and X. aotearoae were present among the isolates. L. macrocystis and X. aotearoae constitute new records for the marine flora of the New Zealand archipelago, on genus and species level. The red algal endophyte Mikrosyphar pachymeniae LINDAUER previously described from New Zealand is possibly synonymous with Microspongium tenuissimum.
The prevalence of infection by Laminariocolax macrocystis was investigated in three populations of Macrocystis pyrifera along the Otago coast. Two of the populations situated inside and at the entrance of Otago Harbour showed high infection rates (average between 95 and 100%), while an offshore population was less infected (average of 35%).
The phylogenetic affinities of the parasitic brown alga Herpodiscus durvillaeae, an obligate endophyte of Durvillaea antarctica (Fucales, Phaeophyceae) in New Zealand, were investigated. Analyses combined nuclear encoded ribosomal and plastid encoded RuBisCO genes. Results from parsimony, distance and likelihood methods suggest a placement of this species within the order Sphacelariales. Even though H. durvillaeae shows a reduced morphology, molecular data were supported by two morphological features characteristic for the Sphacelariales: the putative presence of apical cells and the transistory blackening of the cell wall with 'Eau de Javelle'.
Ultrastructural sections showed evidence for a symplastic contact between the cells of the parasite H. durvillaeae and its host D. antarctica. Within the host cortex, parasite cells attack the fields of plasmodesmata connecting host cells. In these areas, parasite cells squeeze between the host cells and form secondary plasmodesmata connecting the primary plasmodesmata of the host cells with the cytoplasma of the parasite cell.
Moreover, despite being described as lacking pigments, H. durvillaeae possesses a rbcL gene, and its plastids show red autofluorescence in UV light, suggesting the presence of a possibly reduced, but functional photosynthetic apparatus. Vestigial walls between developing spores in the 'secondary unilocular sporangia' of H. durvillaeae confirm the identity of these sporangia as plurilocular gametangia, derived from reduced gametophytes which were entirely transformed into gametangia.
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Givernaud, Thierry. "Recherches sur la Pheophycée Sargassum muticum (Yendo) Fensholt en Basse-Normandie : étude des peuplements, influence de l'environnement sur le développement, régénération in vitro, essais de valorisation." Caen, 1988. http://www.theses.fr/1988CAEN2027.
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Etude des peuplements le long des côtes et estimation de la biomasse exploitable. Etude au laboratoire de l'influence des principaux facteurs du milieu sur la croissance et du développement de l'algue. Morphogénèse des boutures, capacité de régénération. Valorisation par mise au point à une technique d'obtention d'un extrait liquide dont on étudie l'activité sur des plantes horticoles
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Fraser, Ceridwen, and n/a. "Phylogeography of the kelp genus Durvillaea (Phaeophyceae: Fucales)." University of Otago. Department of Zoology, 2009. http://adt.otago.ac.nz./public/adt-NZDU20091002.131226.
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Durvillaea, a kelp genus occurring only in the Southern Hemisphere, presents an ideal system for studies of marine connectivity and postglacial recolonisation. Durvillaea contains five currently-recognised species, four of which are non-buoyant. Whereas all non-buoyant species are restricted to the south-western Pacific, the sole buoyant species (D. antarctica) has a far wider, circumpolar distribution, strongly suggesting that long-distance dispersal in D. antarctica is achieved by rafting. This contrast in predicted dispersal ability among Durvillaea species provides an opportunity for natural phylogeographic comparisons, thereby assessing the effectiveness of rafting as a long-distance dispersal mechanism. Additionally, the inability of D. antarctica to survive in ice-affected areas, combined with its broad distribution, make it an ideal candidate for studies of postglacial recolonisation.
Phylogenetic and biogeographic relationships within Durvillaea were here assessed using sequence data from mitochondrial (COI), chloroplast (rbcL) and nuclear (18S) DNA. Genetic data were obtained from more than 500 specimens, including representatives from across the geographic range of each recognised species of Durvillaea. Mitochondrial data for Durvillaea were found to be highly phylogenetically informative, with 117 variable sites observed over a 629 bp fragment of COI. Chloroplast and nuclear markers, on the other hand, showed less variation than COI, but nonetheless contributed useful phylogenetic information. Phylogenetic analyses were performed using both Maximum Likelihood and Bayesian approaches.
Contrasting patterns of genetic diversity were observed across the range of D. potatorum in Australia, with genetic homogeneity throughout western sites versus relatively high levels of diversity in eastern populations. Based on these results, I hypothesise that D. potatorum recolonised much of the western part of its range postglacially, perhaps being entirely eliminated from western Tasmania during the last glacial period by altered oceanographic systems. Additionally, 'western' and 'eastern' D. potatorum haplotypes formed deeply-divergent clades, likely reflecting geographic isolation on either side of the Bassian Isthmus during Pleistocene marine regressions.
Substantial genetic diversity was observed across the range of the circumpolar species D. antarctica. Within New Zealand, phylogenetic and morphological analyses of D. antarctica indicate that two morphotypes ('cape' and 'thonged' forms) likely represent reproductively isolated species, with the 'cape' lineage apparently restricted to southern New Zealand. Whereas the 'cape' lineage showed little genetic variation throughout its range, the 'thonged' lineage exhibited marked phylogeographic structure, with high genetic diversity and a clear north - south genetic disjunction delineated by the Canterbury Bight.
On a broader, circumpolar scale, D. antarctica showed contrasting patterns of genetic diversity, with high levels of variation in low-latitude regions (e.g., continental coasts of New Zealand and Chile), versus near-homogeneity at high, subantarctic latitudes. These phylogeographic contrasts strongly suggest that D. antarctica recolonised much of the subantarctic region only recently, most plausibly following extirpation by ice scour at the Last Glacial Maximum (LGM). Locations of putative recolonised islands relative to 'refugial' areas indicate that Antarctic sea ice was likely more extensive at the LGM than previous studies have suggested.
Latitudinal contrasts in genetic diversity were also observed among Chilean populations of D. antarctica, with a single mitochondrial haplotype detected throughout Chilean Patagonia versus high diversity in central Chile (32�-42�S). The Patagonian populations appear to have recolonised the region postglacially, following recession of the Patagonian Ice Sheet after the LGM. These populations show transoceanic ancestry, with a closer relationship to populations in the subantarctic and southern New Zealand regions than to those in central Chile. Substantial phylogeographic structure was evident across small spatial scales in central Chile, and the correspondence of major genetic disjunctions among central Chilean sites with the presence of long stretches of unsuitable substrate (beaches) strongly suggests that habitat discontinuity drives genetic isolation in this dispersive species.
Broad-scale molecular phylogenetic analyses indicate that the current taxonomy of Durvillaea species requires substantial revision. Previously-recognised 'morphotypes' of Durvillaea (of D. potatorum in Australia, and D. antarctica in New Zealand), for example, were here found to be genetically distinct, likely representing reproductively-isolated species.
This phylogeographic research on Durvillaea kelp sheds new light on the historical impacts of climate change on Southern Hemisphere marine environments, and on the processes driving evolution in a marine macroalga.
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Nehr, Zofia. "Analyse génétique et fonctionnelle du mutant de morphogenèse étoile de l'algue brune ectocarpus siliculosus." Paris 6, 2013. http://www.theses.fr/2013PA066766.
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Les Phaeophyceae ont acquis la multicellularité indépendamment des autres lignées multicellulaires, elles offrent donc la possibilité d’étudier des mécanismes de développement nouveaux et originaux. Ectocarpus siliculosus est l’espèce modèle pour les algues brunes, et les étapes de développement du sporophyte ont été décrites précisément. Pour comprendre leurs bases génétiques et moléculaires, une approche de génétique directe a été adoptée. Le mutant étoile est le premier mutant de morphogenèse décrit de manière exhaustive, sa mutation, simple locus et récessive, découple le tempo et la position de ramification en raison d’un défaut de différenciation cellulaire qui conduit à la sur-ramification. Le rhizoïde du gamétophyte est lui aussi affecté, il rappelle le phénotype du sporophyte. Les deux phénotypes semblent génétiquement liés, et il est probable qu’ils soient dus à la mutation etl. Le locus ETL a été identifié par une approche de clonage positionnel. Le génome du mutant étoile a été séquencé (illumina) ce qui a permis par comparaison avec le génome du sauvage de prédire les mutations candidates dans le locus ETL. La seule mutation non-silencieuse affecte une protéine avec deux domaines fonctionnels : un domaine BAR/IMD et un domaine RhoGAP. Les domaines BAR sont impliqués dans la reconnaissance des membranes et sont capables d’inhiber les domaines RhoGAP qui sont des régulateurs des RhoGTPases. Ce gène s’exprimant dans les cellules apicales du filament de l’algue, il pourrait maintenir la croissance apicale polarisée par l’interaction, aux apex, entre ses deux domaines protéique. Le gène ETL est le premier gène de morphogenèse cloné chez E. Siliculosus, il ouvre d’immenses perspectives en terme de caractérisation fonctionnelle et d’approches « evo-devo »Multicellularity has occurred independently in Phaeophyceae and in other multicellular lineages. Therefore these organisms offer the opportunity to study novel and alternative developmental processes. Ectocarpus siliculosus is the model species for brown algae and the development of its early sporophyte has been described precisely. To understand the genetic and molecular basis of this development, a forward genetic approach has been carried out. The mutant étoile is the first morphogenetics mutant exhaustively described. Its single locus and recessive mutation, leads to a defect in cell differentiation that decouples branching tempo and position leading to a hyperbranched phenotype. Gametophyte rhizoïde is modifoed as well, it resembles the étoile early sporophyt phenotype. The two phenotypes are genetically linked and thought to be induced by the etl mutation. The ETL locus has been identified by a map-based approach. The illumina sequencing of the mutant genome allowed to propose candidate mutations. The only non-silent mutation affects a protein with two functional domains: a BAR/IMD domain and RhoGAP domain. BAR/IMD domains can recognize lipid membranes and are able to inhibit RhoGAP domains which are regulators for RhoGTPases. As ETL is expressed in the filamentous apical cells, it could maintain tip-growth in the apices through interaction between its two domains. ETL gene is the first morphogenetic gene that has been cloned, and hence it opens hudge perspectives for functional characterization and evo-devo studies
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Rodrigues, Maria Elisa Cairrão Rodrigues. "Fucus spp. (Phaeophyceae, Heterokontophyta) como indicador de contaminação ambiental." Master's thesis, Universidade de Aveiro, 2003. http://hdl.handle.net/10773/21745.
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Mestrado em ToxicologiaO género Fucus apresenta vasta distribuição na zona costeira Ibérica, tendo sido descritas cinco espécies para Espanha e quatro para Portugal (Fucus spiralis L., F. vesiculosus L., F. ceranoides L. e F. serratus L.). Possui enorme importância, tanto ecológica como comercial, essencialmente na produção de produtosnaturais medicinais. As espécies deste género surgem em diversos locais, incluindo os expostos a descargas de efluentes urbanos, industriais e aos lixíviados de terrenos agrícolas, encontrando-se normalmente nas zonas rochosas, onde sofrem zonação notória, que é controlada por complexas interacções fisiológicas e biológicas. O objectivo principal deste trabalho consistiu em efectuar os estudos de base necessários à utilização de espécies do género Fucus como bioindicadores em programas de biomonitorização em zonas costeiras e estuarinas da costa Noroeste de Portugal. Para atingir este objectivo foram desenvolvidos três trabalhos específicos: 1) analisar a variação morfológica de três espécies de Fucus (F. ceranoides, F. spiralis e F. vesiculosus), recolhidos na costa Noroeste Atlântica de Portugal entre o estuário do rio Minho e a Ria de Aveiro durante um ano, e o estabelecimento de correlações com os parâmetros ambientais; 2) avaliar o potencial de bioacumulação de mercúrio das espécies de Fucus [F. ceranoides, F. spiralis (F. spiralis var. platycarpus e F. spiralis var. spiralis) e F. vesiculosus]; 3) desenvolver e validar a metodologia necessária à utilização da actividade de glutationa S-transferase (GST) de Fucus spp. como biomarcador de contaminação ambiental. Através da Análise Canónica de correspondência foi possível perceber que o factor ambiental preponderante na variação dos parâmetros morfométricos parece ser a temperatura, estando este intimamente relacionado com o pH e a salinidade, em todas as espécies analisadas. A quantificação de mercúrio em três partes estruturais (receptáculos, lâmina e base) das espécies de Fucus, permitiu observar que os receptáculos continham menor concentração do que a base e a lâmina. Os valores obtidos para o sedimento apresentaram-se concordantes com os obtidos no material biológico (apesar dos espécimes consistentemente registarem concentrações superiores). Estes resultados sugerem que as espécies e variedades de Fucus estudadas são boas bioindicadores da contaminaçãopor mercúrio, em ecossistemas marinhos e estuarinos. F. ceranoides, F. spiralis var. platycarpus e F. vesiculosus apresentaram os valores mais baixos da actividade da GST nos locais de referência. As estações de amostragem, localizadas em áreas com reconhecida contaminação por hidrocarbonetos aromáticos policíclicos (HAPs), apresentaram valores mais elevados de actividade de GST, sugerindo indução dos mecanismos de destoxificação. Este facto não foi, no entanto, observado em F. spiralis var. spiralis.
The genus Fucusexhibits a wide distribution on the Iberian coast. Five species have been described for Spain and four for Portugal (Fucus spiralis L., F. vesiculosus L., F. ceranoides L. and F. serratus L.). This genus is of enormous importance, both from ecological and commercial (essentially in the production of natural medicinal products) points of view. Fucus spp. exists in several sites, including those receiving urban and industrial effluent discharges and leachates from farmland. The species of the Fucus genus are mainly found in rocky areas, where conspicuous zonation occurs, which is controlled by complex physiological and biological interactions. The main aim of this study was to launch the necessary basis to validate the use of the Fucusspecies as bioindicators in coastal and estuarine environments. To achieve this objective three steps with specific objectives were outlined: 1) analysis of morphologic variation in three species of Fucus (F. ceranoides, F. spiralis and F. vesiculosus), collected during a year, from the Portuguese Northwestern Atlantic coast (between the estuary of Minho river and the Aveiro tidal lagoon), and the establishment of correlations with environmental parameters; 2) evaluation of the potential of Fucus [F. ceranoides, F. spiralis (F. spiralis var. platycarpus and F. spiralis var. spiralis) and F. vesiculosus] to bioacumulate mercury; 3) to develop and validate the necessary methodologies for the application of Fucus spp. glutatione S-transferase as a biomarker of environmental contamination. Canonical correspondence analysis indicates that the dominant factor influencing morphometric parameters is temperature, always in close correlation with pH and salinity. Quantification of mercury in the three structural parts considered (receptacles, stipe and holdfast) showed that the receptacles consistently showed the lowest concentrations throughout the entire sampling campaign. Values obtained for the sediment were always consistent with the ones obtained for specimens, (the latter always presented higher concentrations). This leads to the conclusion that Fucuscan be considered a good bioindicator for mercury contamination in coastal and estuarine environments. As expected, F. ceranoides, F. spiralis var. platycarpus and F. vesiculosus registered the lowest values of GST activity in the reference stations. Sampling stations located in areas were contamination by polycyclic aromatic hydrocarbons (PAHs) is well known, showed higher values of activity for this enzyme, suggesting that detoxification mechanisms were induced.However, a different pattern was observed for F. spiralis var. spiralis.
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Mungioli, Mariana. "Estudos morfológicos e moleculares de algas pardas filamentosas (Phaeophyceae) no litoral sudeste do Brasil." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-25052017-092433/.
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As algas pardas filamentosas (Phaeophyceae) constituem um grupo essencialmente marinho com morfologia extremamente simples. A identificação taxonômica dessas algas é bastante difícil quando empregados apenas caracteres morfológicos devido à grande plasticidade fenotípica que apresentam. No Brasil, nenhum estudo sistemático foi feito com seus representantes empregando-se dados moleculares. Neste contexto, a diversidade de algas pardas filamentosas dos gêneros Acinetospora, Asteronema, Bachelotia, Ectocarpus, Hincksia e Feldmannia foi investigada pela primeira vez no Brasil sob uma abordagem molecular, complementada com dados morfológicos. As coletas abrangeram a região sudeste do Brasil, incluindo a área de ressurgência dos litorais do Rio de Janeiro e Espírito Santo, que abriga quase que a totalidade de táxons de algas pardas filamentosas citadas para o país. Foi utilizado o marcador mitocondrial do tipo DNA Barcode, COI-5P e o marcador plastidial para inferências filogenéticas, o rbcL. Os estudos moleculares e morfológicos permitiram identificar 10 táxons para o litoral sudeste brasileiro: oito da ordem Ectocarpales: Acinetospora filamentosa, \"Feldmannia\" irregulares, \"Feldmannia irregulares\" 1, \"Feldmannia irregulares\" 2, \"Feldmannia\" mitchelliae, \"Hincksia\" conífera e Hincksia sandriana (família Acinetosporaceae) e Ectocarpus fasciculatus (família Ectocarpaceae) e dois da ordem Scytothamnales: \"Asteronema\" breviarticulatum (família Asteronemataceae) e Bachelotia antillarum (família Bachelotiaceae). A família Acinetosporaceae não é monofilética e se dividiu em dois agrupamentos, Acinetosporaceae 1, que incluiu a maioria dos representantes brasileiros e a espécie tipo da família, Acinetospora crinita, e para o qual o nome da família deve ser retido; e Acinetosporaceae 2, que incluiu os autênticos gêneros Feldmannia, Hincksia e Pylaiella com suas respectivas espécies-tipo, Feldmannia lebelli, Hincksia hincksiae e Pylaiella litorallis, respectivamente, e para o qual, uma nova família deverá ser proposta. Hincksia sandriana foi a única espécie estudada que se agrupou no clado do autêntico gênero Hincksia e é citada pela primeira vez para o Brasil, constituindo um caso de introdução recente. Para os demais representantes agrupados em Acinetosporaceae 1, excluindo Acinetospora, um novo gênero para a ciência deverá ser proposto. Os táxons \"H.\" conífera, \"F.\" irregulares, \"F. irregulares\" 1, \"F. irregulares\" 2 e \"F.\" mitchelliae não pertencem aos autênticos gêneros Feldmannia e Hincksia, já que não se agruparam com as respectivas espécies-tipo dos gêneros, e, portanto, devem ser transferidos para o novo gênero. As análises com os dois marcadores moleculares demonstraram que \"F.\" irregulares, \"F. irregulares\" 1 e \"F. irregulares\" 2, previamente citados sob uma única espécie (F. irregulares), representam três entidades taxonômicas independentes. Sequências do COI-5P de F. irregulares da Itália, considerada próxima à localidade tipo (Mar Adriático), confirmaram que parte do material analisado deve ser mantido sob o epíteto irregulares, enquanto duas novas espécies devem ser propostas para a ciência para acomodar \"F. irregulares\" 1 e \"F. irregulares\" 2. As análises moleculares com o COI-5P dividiu \"F.\" mitchelliae em três agrupamentos com alta divergência genética e variabilidade morfológica indicando que \"F.\" mitchelliae forma um complexo. Uma sequência de \"F.\" mitchelliae procedente dos EUA (Carolina do Norte), próxima à localidade tipo (Massachusetts), gerada no presente estudo, confirmou que o material brasileiro deve ser descrito sob o epíteto mitchelliae, porém acomodado sob um novo gênero. Nossos resultados moleculares demonstraram claramente que o gênero Acinetospora não é monofilético. Acinetospora filamentosa é citada pela primeira vez para o Oceano Atlântico e foi revelada por meio de dados moleculares, tanto pelo COI-5P quanto pelo rbcL. A espécie Acinetospora crinita referida previamente para o litoral sudeste do Brasil não foi recoletada neste estudo. Diferenças morfológicas nas estruturas pluriloculares entre as duas espécies e ausência de monosporângios em A. filamentosa, descritos como típico apenas para A. crinita, confirmaram a ocorrência de A. filamentosa para o Atlântico. Nossos resultados com o rbcL revelaram que a família Asteronemataceae não é monofilética. O táxon \"Asteronema\" breviarticulatum se agrupou com Asterocladon lobatum, espécie tipo do gênero, e deve ser alocado na família Asterocladaceae, assim como transferido para o gênero Asterocladon propondo-se uma combinação nova para resolver o posicionamento taxonômico dessa espécie. A alta divergência genética verificada para os marcadores COI-5P e rbcL demonstraram que Bachelotia antillarum é uma espécie críptica. A utilização da ferramenta molecular no estudo de algas pardas filamentosas na região sudeste do Brasil foi fundamental para desvendar a sua diversidade, que comprovadamente estava subestimada, assim como melhor delimitar seus gêneros e espécies e revelar espécies crípticas. Os dados aqui apresentados são pioneiros e constituem uma fonte relevante de informação sobre a taxonomia e sistemática deste grupo de algas pardas. Mais investigações por meio de uma ampla revisão, especialmente da família Acinetosporaceae, uma maior amostragem no litoral brasileiro e inclusão de mais gêneros de algas pardas filamentosas nas análises podem ainda mudar o panorama da classificação desse grupoFilamentous brown algae (Phaeophyceae) constitute an essentially marine group that display an extremely simple morphology. The taxonomic identification of these algae is very difficult when based only on morphological characters, due to the high incidence of phenotypic plasticity. In Brazil, no systematic study using molecular data has investigated their representatives. In this context, this study aims to investigate the diversity of filamentous brown algae of the genera Acinetospora, Asteronema, Bachelotia, Ectocarpus, Hincksia and Feldmannia for the first time in Brazil, applying the molecular approach coupled with morphological data. The sampling sites covered the southeastern region of Brazil, including the upwelling area of the Rio de Janeiro and Espírito Santo coasts, which include almost all the filaments of brown algae mentioned for the country. The DNA barcode mitochondrial marker, COI-5P, and the plastid marker for phylogenetic inferences, rbcL, were sequenced. The molecular and morphological studies allowed the recognition of 10 taxa on the Brazilian southeastern coast, out of which eight taxa correspond to the order Ectocarpales, and two to the order Scytothamnales. Ectocarpales is represented by the families Acinetosporaceae (Acinetospora filamentosa, \"Feldmannia\" irregularis, \"Feldmannia irregularis\" 1, \"Feldmannia irregularis\" 2, \"Feldmannia\" mitchelliae, \"Hincksia\" conifer and Hincksia sandriana), and Ectocarpaceae (Ectocarpus fasciculatus). The order Scytothamnales, in turn, includes the families Asteronemataceae (\"Asteronema\" breviarticulatum) and Bachelotiaceae (Bachelotia antillarum) The Acinetosporaceae family is non-monophyletic and was divided into two clusters: Acinetosporaceae 1 for which the family name should be retained, included the type species of the family (Acinetospora crinite) and most of the Brazilian representatives; and Acinetosporaceae 2 for which a new family should be proposed, included the genera Feldmannia, Hincksia and Pylaiella represented by their respective type species, Feldmannia lebelli, Hincksia hincksiae and Pylaiella litorallis. Hincksia sandriana was the only species studied that grouped in the clade of the authentic genus Hincksia. Besides, this is the first record of H. sandriana for Brazil, which constitutes a case of recent introduction. For the other representatives of Acinetosporaceae 1, except Acinetospora, a new genus for science should be proposed. The taxa \"H.\" conifer, \"F.\" irregularis, \"F. irregularis\" 1, \"F. irregularis\" 2 and \"F.\" mitchelliae do not belong to the authentic genera Feldmannia and Hincksia, since they did not group with the respective generitypes. Therefore, should be transferred to the new genus. Analyzes applying both molecular markers showed that \"F.\" irregularis, \"F. irregularis\" 1 and \"F. irregularis\" 2, previously cited as a single species (F. irregularis), constitute three independent taxonomic entities. COI-5P sequences of F. irregularis from Italy, close to the type locality (Adriatic Sea), demonstrate that part of the analyzed material should be maintained under the epithet irregularis, whereas two new scientific species should be proposed to accommodate \"F. irregularis \"1 and \" F. irregularis \"2. COI-5P molecular analyzes divided \"F.\" mitchelliae into three clusters with high genetic divergence and morphological variability indicating that \"F.\" mitchelliae corresponds to a species complex. A sequence of \"F. mitchelliae from the United States (North Carolina), near the type locality (Massachusetts), obtained and included in the present study, confirmed that the Brazilian material should be described under the epithet mitchelliae and transferred to a new genus. Our molecular results have clearly demonstrated that the genus Acinetospora is non-monophyletic. Acinetospora filamentosa is for the first time mentioned for the Atlantic Ocean and was revealed by molecular data, both by COI-5P and rbcL. The species Acinetospora crinite recorded on the southeastern coast of Brazil was not collected in this study. Morphological differences in plurilocular structures between two species and absence of monosporangia in A. filamentosa, described as typical only for A. crinite, confirmed the occurrence of A. filamentosa for the Atlantic. Our results with the rbcL revealed that the family Asteronemataceae is non-monophyletic. \"Asteronema\" breviarticulatum was grouped with Asterocladon lobatum, the type species of the genus, and should be transferred to the genus Asterocladon and to the family Asterocladaceae. Consequently, a new combination should be proposed to solve taxonomic placement of this species. The high genetic divergence observed for the COI-5P and rbcL markers demonstrated that Bachelotia antillarum is a cryptic species. The use of the molecular tool in the study of filamentous brown algae in the southeastern region of Brazil was fundamental to uncover their diversity, previously underestimated, as well as to allow a better delimitation of their genera and species. The innovative data presented here constitute a relevant source of information to the taxonomy and systematics of filamentous brown algae. More investigations through a broad review, especially of the Acinetosporaceae family, a wider sampling in the Brazilian coast and the inclusion of more genera of filamentous brown algae in the analyses can still change the classification scenario of this group
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Figueiredo, Camila Silva de. "Contribuição à quimiotaxonomia e ficoquímica de Canistrocarpus cervicornis (Kützing) De Paula & De Clerk (Dictyotaceae) : coletada nos litorais paraibano e fluminense." Universidade Federal da Paraíba, 2013. http://tede.biblioteca.ufpb.br:8080/handle/tede/8056.
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Marine biodiversity is presented as a promising source of new substances with high biological potential. Among the many organisms that inhabit the marine environment, we stress the brown algae belonging to the family Dictyotaceae. Genus Canistrocarpus was recently established, and some algae Dictyota formerly were reclassified as Canistrocarpus. This work describes the results of the phycochemical study of Canistrocarpus cervicornis (formerly classified as Dictyota pulchella), and the evaluation of the phycochemical profile of C. cervicornis collected on the coast of Paraíba and the coast of Rio de Janeiro, which contributed to the correct name of Dictyota pulchella as Canistrocarpus cervicornis. Alga samples were collected at Bessa Beach (coordinates 07º04'01 '' S and 34º49'35 '' W), city of João Pessoa (PB) in August 2010 and December 2012. The material was dried at room temperature and extraction was performed with CH2Cl2 : MeOH (2:1). The material was dried at room temperature in fresh air and extraction was performed with CH2Cl2: MeOH (2:1). The extract obtained the first collection was subjected to vacuum filtration on silica gel with solvent hexane, ethyl acetate and methanol in increasing gradient of polarity. The fraction hexane : ethyl acetate (85:15) was subjected to column chromatography yielded one new natural product, the dolastane diterpene 4,7-diacetoxy dichotenone A. The extract resulting from the second collection was divided in two parts. The first part was subjected to column chromatography resulted in the isolation of a known dolastane diterpene, 4-acetoxy-14-hidroxydolast-1(15),7,9-triene. A second aliquot of the extract was acetylated and subjected to column chromatography, which led to the isolation of three diterpenes, one dolastane unpublished in the literature, 4-desoxy-amijidictyol and two known secodolastanes, isolinearol acetate and indicol. Chemical constituents isolated were identified by spectroscopic methods 1H and 13C-1D and 2D NMR, optical rotation and comparison with literature data. This study contributed to the chemotaxonomy of the tribe Dictyoteae, especially C. cervicornis.
A biodiversidade marinha apresenta-se como uma fonte promissora de novas substâncias com grande potencial biológico. Dentre os diversos organismos que habitam o ambiente marinho, merecem destaque as algas pardas pertencentes à família Dictyotaceae e gênero Canistrocarpus. Este gênero foi instituído recentemente, e algumas algas anteriormente denominadas Dictyota foram reclassificadas como Canistrocarpus. O presente trabalho descreve os resultados do estudo ficoquímico de Canistrocarpus cervicornis (anteriormente classificada como Dictyota pulchella), envolvendo a avaliação do perfil ficoquímico de C. cervicornis coletada no litoral da Paraíba e no litoral do Rio de Janeiro. Este estudo contribuiu para a correta denominação da então D. pulchella em C. cervicornis. As amostras da alga foram coletadas na Praia do Bessa (coordenadas 07º04’01’’ S e 34º49’35’’ W) na cidade de João Pessoa (PB), em agosto de 2010 e em dezembro de 2012. A secagem foi realizada a temperatura ambiente, em local arejado e a extração procedida com CH2Cl2:MeOH (2:1). O extrato resultante da primeira coleta foi submetido a uma filtração a vácuo em sílica gel com os solventes hexano, acetato de etila e metanol em gradiente crescente de polaridade. A fração hexano:acetato de etila (85:15) foi submetida a cromatografia em coluna, de onde se obteve um novo produto natural, o diterpeno dolastano 4,7-diacetoxi de dichotenona A. O extrato resultante da segunda coleta foi dividido em duas partes. Uma alíquota foi submetida à cromatografia em coluna, de onde se obteve o diterpeno dolastano conhecido 4-acetoxi-14-hidroxidolasta-1(15),7,9-trieno. A segunda alíquota do extrato foi acetilada e submetida a cromatografias em coluna, o que levou ao isolamento de três diterpenos, sendo um dolastano inédito na literatura, o 4-desoxi-amijidictyol e dois secodolastanos conhecidos, o acetato de isolinearol e o indicol. Os constituintes químicos isolados foram identificados por análises espectroscópicas de RMN 1H e 13C uni e bidimensionais, rotação ótica, e comparação com dados da literatura. Este estudo contribuiu para a quimiotaxonomia da tribo Dictyoteae, em especial de C. cervicornis.
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Motuhi, Sofia-Elena. "Valorisation de substances naturelles marines de Nouvelle-Calédonie d'intérêt en traitement anticancéreux." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1B050.
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Les systèmes de complexes récifaux de l’archipel de la Nouvelle-Calédonie sont explorés depuis près de quarante années pour leur exceptionnelle biodiversité. En effet, de part une position sous-tropicale unique, proche de zones tectoniques actives et du sous-continent Australien, les récifs et lagons néo-calédoniens abritent une importante faune et flore marine relativement protégée des perturbations climatiques. Ces organismes marins se sont avérés être un réservoir considérable de molécules des plus originales et ayant une forte propension à présenter un intérêt thérapeutique notamment dans le cadre du traitement du cancer. L’objectif de cette thèse était de poursuivre cette quête en puisant les substances naturelles dans des macroalgues de Nouvelle-Calédonie. La modulation de la mort cellulaire programmée a notamment été ciblée. Ainsi, les travaux réalisés sur sept espèces de macroalgues rouges (Rhodophyceae) et brunes (Phaeophyceae) collectées dans le lagon Sud de la Nouvelle-Calédonie (arrêté N°197-2016/ARR/DENV) ont permis de révéler leur potentiel dans l’inhibition de la prolifération de cellules cancéreuses en culture. Une espèce de macroalgue rouge a plus particulièrement été travaillée et a conduit à la caractérisation de deux molécules bioactives, dont une n’avait pas été décrite auparavant. L’étude de leur mécanisme d’action cellulaire a révélé que celles-ci pouvaient constituer de nouvelles pistes thérapeutiques intéressantes dans la recherche de nouveaux traitements en chimiothérapie en tant qu’agents antimitotiques inhibiteurs de kinase. Des activités biologiques très intéressantes ont également été révélées pour des fractions issues de deux espèces de macroalgues brunes démontrant une sélectivité significative pour les cellules cancéreuses. Inscrite dans la continuité de multiples bioprospections menées dans les lagons de Nouvelle-Calédonie à la recherche de produits naturels marins d’intérêt thérapeutique, cette thèse de doctorat témoigne du potentiel de plusieurs espèces de Rhodophyceae et Phaeophyceae jusqu’alors très peu explorées chimiquementMarine zones associated with coral reef systems of the New Caledonia archipelago have been investigated for almost forty years with respect to their plant and invertebrate biodiversity and chemodiversity. In particular, thanks to their unique subtropical position close to tectonically active zones and to the Australian subcontinent, the complex reef systems of New Caledonia’s lagoons are home to a highly diverse marine fauna that is relatively protected from climatic disturbances. This is reflected by the score of novel bioactive molecules that have been discovered and characterized, several of which have been actively investigated for their antineoplastic and antitumoral potential activities. We paid particular attention to macroalgal species that induce programmed cell death, as an approach to detecting original anticancer bioactivities. Seven species of red (Rhodophyceae) and brown (Phaeophyceae) macroalgae collected in the South lagoon of New Caledonia (decree N°197-2016/ARR/DENV) have demonstrated interesting in vitro anticancer activity. In particular, one red macroalgal species led to the characterization of two bioactive natural products, the structure of one of which has not been described to date. Biological tests have shown that these two compounds could be promising candidates as antimitotic kinase inhibitors agents for the development of targeted anticancer chemotherapies. Interesting biological activities have also been revealed from several molecular isolates from two species of brown macroalgae, showing high selectivity towards non-cancerous cells. In the continuing investigations of the therapeutic potential of natural products isolated from New Caledonian marine organisms, this doctoral thesis has highlighted the therapeutic potential of several species of Rhodophyceae and Phaeophyceae which has hitherto been largely unexplored
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Oppliger, Zan Luz Valeria. "Reproduction des grandes algues brunes des côtes Chiliennes et Bretonnes en marge de leur aire de distribution." Paris 6, 2010. http://www.sb-roscoff.fr/images/stories/sbr/Edition-communication/theses/PHD-Thesis-oppliger.pdf.
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Le développement, la reproduction et la survie d’un organisme, dépendent de son environnement physique et/ou écologique. La sélection en faveur de certains traits d’histoire de vie découle donc de la stabilité de l’environnement (i. E. Reproduction sexuée versus asexuée). La stratégie de reproduction d’une espèce est par conséquent susceptible de se modifier en fonction des changements environnementaux, pouvant survenir en limite d’aire de distribution qui se caractérisent par des fluctuations abiotiques plus importantes. Les grandes algues brunes (Phaeophyceae, Laminariales) sont des espèces structurant les communautés benthiques marines. Elles présentent un cycle de reproduction hétéromorphe avec alternance de phase haploïde microscopique (gamétophyte) et de phase diploïde macroscopique (sporophyte). Les connaissances sur la biologie et la distribution géographique de la plupart de ces espèces n’étaient basées jusqu’à présent que sur l’étude des sporophytes. Mes travaux de thèse ont permis de mettre en évidence l’importance de ces gamétophytes dans le maintien des populations, en comparant les modes de reproduction de trois espèces de laminaires. Les résultats suggèrent que le déterminisme du sexe est principalement génétique et que l’effet de la température de l’eau de mer sur la phase microscopique peut expliquer les distributions géographiques de certaines espèces. Par ailleurs, différents stratégies reproductives ont été observées au sein et entre espèces suggérant l’existence de phénomènes d’adaptations locales. En particulier, en limite d’aire de distribution des espèces, nos résultats montrent l’existence de la parthénogenèse géographique.
Books on the topic "Phaeophycae"
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Kitayama, Taiju. A Taxonomic study of the japanese Sphacelaria (Sphacelariales, Phaeophyceae). Tokyo: National Science Museum, 1994.
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Marine algae of the northern Gulf of California: Chlorophyta and Phaeophyceae. Washington, D.C: Smithsonian Institution Scholarly Press, 2010.
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Norris, James N. Marine algae of the northern Gulf of California: Chlorophyta and Phaeophyceae. Washington, D.C: Smithsonian Institution Scholarly Press, 2010.
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Norris, James N. Marine algae of the northern Gulf of California: Chlorophyta and Phaeophyceae. Washington, D.C: Smithsonian Institution Scholarly Press, 2010.
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Parente, Manuela. Studies on the families Lithodermataceae, Nemodermataceae, Punctariaceae and Scytosiphonaceae (Phaeophyta) in the Azores. Portsmouth: University of Portsmouth, 2002.
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Farrell, Paul. A study of the recently introduced macroalga Undaria pinnatifida (Harvey) Suringar (Phaeophyceae laminariales) in the British Isles. Portsmouth: University of Portsmouth, Institute of Marine Sciences, 2003.
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Athanasiadis, A. Taxonomisk litteratur och biogeografi av skandinaviska rödalger och brunalger =: Bibliography and biogeography of Scandinavian Rhodophyta and Phaeophyta. Göteborg: Algologia, 1996.
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Hakubutsukan, Ōsaka Shiritsu Shizenshi. Nihon-san kaisō hyōhon mokuroku.: List of seaweed specimens in the herbarium of the Osaka Museum of Natural History. Chlorophyceae and phaeophyceae. Ōsaka-shi: Ōsaka Shiritsu Shizenshi Hakubutsukan, 1988.
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Seto, Kō. Nihon-san kaisō hyōhon mokuroku: Ryokusō kassō hen : List of seaweed specimens in the herbarium of the Osaka Museum of Natural History. Chlorophyceae and phaeophyceae. Ōsaka-shi: Ōsaka Shiritsu Shizenshi Hakubutsukan, 1988.
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Seaweeds Of The British Isles Fucophyceae Phaeophyceae V. Pelagic Publishing Ltd, 1987.
Find full textBook chapters on the topic "Phaeophycae"
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Kawai, Hiroshi, and Eric C. Henry. "Phaeophyta." In Handbook of the Protists, 1–38. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-32669-6_31-1.
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Kawai, Hiroshi, and Eric C. Henry. "Phaeophyta." In Handbook of the Protists, 267–304. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-28149-0_31.
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Dahlgren, Gertrud, and Meinrad Küttel. "Abteilung Phaeophyta (Braunalgen)." In Systematische Botanik, 45–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-71611-9_13.
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Wehr, John D. "Brown Algae (Phaeophyceae) in Rivers." In River Algae, 129–51. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-31984-1_6.
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Peters, Akira F., and Britta Schaffelke. "Streblonema (Ectocarpales, Phaeophyceae) infection in the kelp Laminaria saccharina (Laminariales, Phaeophyceae) in the western Baltic." In Fifteenth International Seaweed Symposium, 111–16. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-1659-3_15.
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Schmid, Christine E. "Cell-cell-recognition during fertilization in Ectocarpus siliculosus (Phaeophyceae)." In Fourteenth International Seaweed Symposium, 437–43. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1998-6_57.
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Maier, Ingo. "Environmental and Pheromonal Control of Sexual Reproduction in Laminaria (Phaeophyceae)." In Proceedings in Life Sciences, 66–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-72604-0_9.
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Schnetter, Reinhard, Ingrid Hörnig, and Gisela Weber-Peukert. "Taxonomy of some North Atlantic Dictyota species (Phaeophyta)." In Twelfth International Seaweed Symposium, 193–97. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-4057-4_27.
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Kawashima, Yukio, and Hiroshi Tokuda. "Callus formation in Ecklonia cava Kjellman (Laminariales, Phaeophyta)." In Thirteenth International Seaweed Symposium, 375–80. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-2049-1_53.
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Parente, M. I., R. L. Fletcher, and A. I. Neto. "New records of brown algae (Phaeophyta) from the Azores." In Island, Ocean and Deep-Sea Biology, 153–57. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-017-1982-7_15.
Full textConference papers on the topic "Phaeophycae"
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Moreira, Ramón, Santiago Vilas Arufe, Jorge Sineiro, and Francisco Chenlo. "Effect of air drying temperature on phytochemical properties of brown seaweed Bifurcaria bifurcata." In 21st International Drying Symposium. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/ids2018.2018.7496.
Full textAbstract:
The purpose of this study was to determine the effects of convective air-drying at different temperatures (35, 50, 60 and 75°C) on the color of Bifurcaria bifurcata (BB) seaweed powders obtained after milling, the antioxidant activity and polyphenolic and carbohydrate content of the aqueous extracts obtained by ultrasound-assisted extraction. BB seaweed powders exhibited significant color differences between powders obtained from BB dried at 35ºC (yellowish-green) and 50–75 °C (brown). High air drying temperature (above 60ºC) significantly reduced the total polyphenolic, carbohydrate content and scavenging activity of aqueous extracts of BB. Keywords: Phaeophyceae Antioxidant activity Carbohydrates Color Polyphenols
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Lemesheva, V. S., E. M. Lukasheva, A. A. Tsarev, A. V. Kushnareva, T. E. Bilova, K. Birkmeier, K. Ealing, A. Zinz, A. A. Frolov, and E. R. Tarakhovskaya. "Characterization of the proteome of functionally differentiated thallus zones of Fucusvesiculosus L. (Phaeophyceae)." In IX Congress of society physiologists of plants of Russia "Plant physiology is the basis for creating plants of the future". Kazan University Press, 2019. http://dx.doi.org/10.26907/978-5-00130-204-9-2019-261.
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Чадова, Оксана Андреевна, and Петр Владимирович Веланский. "FATTY ACID COMPOSITION OF ENDOPHYTIC MICROALGAE LAMINARIOCOLAX AECIDIOIDES, STREBLONEMA CORYMBIFERUM AND STREBLONEMA SP. (ECTOCARPALES, PHAEOPHYCEAE)." In Наука. Исследования. Практика: сборник избранных статей по материалам Международной научной конференции (Санкт-Петербург, Апрель 2021). Crossref, 2021. http://dx.doi.org/10.37539/srp296.2021.41.36.008.
Full textAbstract:
Впервые исследован жирнокислотный состав полярных и нейтральных липидов бурых эндофитных микроводорослей Laminariocolax aecidioides, Streblonema corymbiferum и Streblonema sp. Показано, что в состав полярных липидов входят главным образом полиненасыщенные жирные кислоты, такие как 18:3ω-3, 18:4ω-3 и 20:5ω-3. Во фракциях нейтральных липидов всех образцов доминировали насыщенные жирные кислоты 14:0 и 16:0, мононенасыщенная 18:1ω-9 и полиненасыщенная 18:2ω6. Отмечена высокая концентрация 16:1ω-7 в нейтральной фракции Streblonema sp. Во всех липидных фракциях эндофитов, кроме нейтральных липидов S. corymbiferum, обнаружены гидроксилированные жирные кислоты 22:0Δ2-OH и 24:0Δ2-OH. The fatty acid composition of polar and neutral lipids of brown endophytic microalgae Laminariocolax aecidioides , Streblonema corymbiferum and Streblonema sp. was investigated for the first time. It was shown that the composition of polar lipids of endophytes includes mainly polyunsaturated fatty acids, such as 18:3ω-3, 18:4ω-3 and 20: 5ω-3. Saturated 14:0 and 16:0, monounsaturated 18:1ω-9 and polyunsaturated 18:2ω6 dominated the neutral lipids of all samples. A high concentration of 16:1ω-7 was observed in the neutral fraction of Streblonema sp. Hydroxylated fatty acids 22:0Δ2-OH and 24:0Δ2-OH were found in all lipid fractions, except for neutral lipids of S. corymbiferum .
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Wang, Ruipeng, Zeyu Zhang, Xiuli Wang, and Hongyue Wang. "Microsatellite analysis of genetic diversity and population genetic structure of the sporophytes of Undaria pinnatifida (phaeophyceae) in Dalian of China." In 2010 International Conference on Bioinformatics and Biomedical Technology. IEEE, 2010. http://dx.doi.org/10.1109/icbbt.2010.5478976.
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Mansur, K. F. R., P. A. S. Longo, S. G. L. Siqueira, and F. P. P. Leite. "HISTÓRIA DE VIDA E DINÂMICA POPULACIONAL DE HYALE NIGER (HASWELL, 1879) (AMPHIPODA, HYALIDAE) ASSOCIADA A SARGASSUM SP. (PHAEOPHYTA, FUCALES) EM UMA ÁREA COM HISTÓRICO DE CONTAMINAÇÃO." In X Congresso Brasileiro sobre Crustáceos. Sociedade Brasileira de Carcinologia, 2018. http://dx.doi.org/10.21826/2178-7581x2018085.
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Al-AShwal, Aisha Ahmed, Noora Al-Naimi, Jassim Al-Khayat, Bruno Giraldes, Najat Al-Omari, Noora Al-Fardi, Caesar Sorino, and Ekhlas Abdelbari. "Distribution and Diversity of Benthic Marine Macroalgae in Islands around Qatar." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0052.
Full textAbstract:
Extending into the Arabian Gulf, Qatar is surrounded by a number of islands mostly scattered by the eastern coastline. With the unique physical characteristics of the Gulf, which is a highly saline sea with high seawater temperatures, there is an urge need to investigate the macroalgae living in such harsh environment. Macroalgae plays an important role in the food web as they are primary producers and providers of food for other organisms. They also provide shelter and habitat in the marine ecosystem for herbivorous fish and other invertebrate animals. Additionally, macroalgae plays an outstanding role in reducing CO2 from the atmosphere and increasing the level of dissolved oxygen in their immediate environment. However, there are few studies on marine macroalgae in Qatar and no previous studies found related to macroalgae from the islands around Qatar. The present work contributes to the macroalgae research by providing the first survey of distribution and diversity of benthic marine macroalgae in islands around Qatar. The marine benthic green, red and brown macroalgae of intertidal and subtidal in marine zone areas around Qatar were collected during Qatar’s Islands project, which started 2018. The collected macroalgae are documented and a total of 67 species of macroalgae are recorded for all islands around Qatar, 24 Chlorophyta (Green algae), 25 Rhodophyta (Red algae) and 18 species Phaeophyta (Brown algae). The Red algae are dominant taxon in term of species richness, accounting for an average of 37% of the species at all study sites. The islands which had more species are Al-Beshaireya 58 Species, Al-Aaliya 53 Species, Sheraouh 48 Species, Janan 43 Species and Bu Felaita 37 Species. Our results show that islands located at eastern and southeastern coast of Qatar have more diversity of algae species than those located at the western and northwestern coast.