Academic literature on the topic 'Microalgae'
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Journal articles on the topic "Microalgae"
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Ramírez, M. E., Y. H. Vélez, L. Rendón, and E. Alzate. "Potential of microalgae in the bioremediation of water with chloride content." Brazilian Journal of Biology 78, no. 3 (October 23, 2017): 472–76. http://dx.doi.org/10.1590/1519-6984.169372.
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Abstract In this work it was carried out the bioremediation of water containing chlorides with native microalgae (MCA) provided by the Centre for study and research in biotechnology (CIBIOT) at Universidad Pontificia Bolivariana. Microalgae presented an adaptation to the water and so the conditions evaluated reaching a production of CO2 in mg L-1 of 53.0, 26.6, 56.0, 16.0 and 30.0 and chloride removal efficiencies of 16.37, 26.03, 40.04, 25.96 and 20.25% for microalgae1, microalgae2, microalgae3, microalgae4 and microalgae5 respectively. Water bioremediation process was carried out with content of chlorides in fed batch system with an initial concentration of chlorides of 20585 mg L-1 every 2 days. The Manipulated variables were: the flow of MCA3 (10% inoculum) for test one; NPK flow for test two, and flow of flow of MCA3+0.5 g L-1 NPK. Chloride removal efficiencies were 66.88%, 63.41% and 66.98% for test one, two and three respectively, for a total bioprocess time of 55 days.
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Postaue, Najla, Leila Cristina Moraes, and Rosa Maria Farias Asmus. "CHORUME COMO FONTE DE NUTRIENTE NA PRODUÇÃO DA BIOMASSA MICROALGAL." e-xacta 12, no. 2 (March 9, 2020): 11. http://dx.doi.org/10.18674/exacta.v12i2.2746.
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A biomassa de microalgas tem apresentado potencial para produção de biodiesel, contudo a viabilidade do cultivo de microalgas depende de fonte de nutrientes de baixo custo. O presente estudo objetivou utilizar o chorume como fonte de nutrientes para microalgas. Os experimentos foram conduzidos visando avaliar a obtenção da biomassa microalgal, conversão de lipídios e rendimento em ésteres metílicos de ácidos graxos, para os meios de cultivos utilizando 5%, 12% e 20% de chorume, com concentrações de 0,02, 0,05 e 0,08 g N. L-1 e para meio de controle contendo 1% de, Nitrogênio (N), Fósforo (P) e Potássio (K), na concentração de 20 g L-1, 5 g L-1 e 20 g L-1, respectivamente. A microalga utilizada neste trabalho foi a de classe Chlorophyceae e família Coccomyxaceae. Os resultados demonstraram que o meio com concentração de 12% de chorume obteve melhores resultados, possibilitando alcançar 1,19 g de biomassa, conversão de 108,15 mg g-1 de lipídios e conteúdo de ésteres de 410,77mg g-1, a microalga utilizada apresentou ainda predominância dos ácidos graxos palmítico e oleico, apresentando baixa quantidade de ácidos graxos saturados o que pode fornecer ao combustível, resistência ao frio. E tais aspectos demonstraram que o chorume pode ser uma fonte promissora de nutrientes para o cultivo das microalgas estudadas. AbstractMicroalgae biomass has presented potential for biodiesel production, however the viability of microalgae cultivation depends on low cost nutrient source. The present study aimed to use leachate as a source of nutrients for microalgae. The experiments were conducted to evaluate the microalgal biomass, lipid conversion and yield in fatty acid methyl esters, for the culture media using 5%, 12% and 20% leachate, with concentrations of 0.02, 0.05 and 0.08 g N. L-1 and for control medium containing 1% Nitrogen (N), Phosphorus (P) and Potassium (K), at a concentration of 20 g L-1, 5 g L-1 and 20 g L-1, respectively. The microalgae used in this work was Chlorophyceae class and Coccomyxaceae family. The results showed that the medium with a concentration of 12% of leachate obtained better results, allowing to reach 1.19 g of biomass, conversion of 108.15 mg g-1 of lipids and esters content of 410,77 mg g-1. The microalgae used also presented predominance of palmitic and oleic fatty acids, presenting low amount of saturated fatty acids which can provide the fuel with cold resistance. And these aspects demonstrated that the leachate can be a promising source of nutrients for the cultivation of the studied microalgae.
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Gonzalez, Luz E., and Yoav Bashan. "Increased Growth of the Microalga Chlorella vulgariswhen Coimmobilized and Cocultured in Alginate Beads with the Plant-Growth-Promoting Bacterium Azospirillum brasilense." Applied and Environmental Microbiology 66, no. 4 (April 1, 2000): 1527–31. http://dx.doi.org/10.1128/aem.66.4.1527-1531.2000.
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ABSTRACT Coimmobilization of the freshwater microalga Chlorella vulgaris and the plant-growth-promoting bacteriumAzospirillum brasilense in small alginate beads resulted in a significantly increased growth of the microalga. Dry and fresh weight, total number of cells, size of the microalgal clusters (colonies) within the bead, number of microalgal cells per cluster, and the levels of microalgal pigments significantly increased. Light microscopy revealed that both microorganisms colonized the same cavities inside the beads, though the microalgae tended to concentrate in the more aerated periphery while the bacteria colonized the entire bead. The effect of indole-3-acetic acid addition to microalgal culture prior to immobilization of microorganisms in alginate beads partially imitated the effect of A. brasilense. We propose that coimmobilization of microalgae and plant-growth-promoting bacteria is an effective means of increasing microalgal populations within confined environments.
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Barbara Araújo, Wesley Machado, Luiz Rodrigo Ito Morioka, Mayara Mari Murata, Josemeyre Bonifácio Da Silva, and Helio Hiroshi Suguimoto. "Uso de Microalgas como Bioestimuladoras da Germinação de Sementes." UNICIÊNCIAS 26, no. 1 (June 23, 2022): 58–62. http://dx.doi.org/10.17921/1415-5141.2022v26n1p58-62.
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As microalgas possuem diversas aplicações biotecnológicas e dentro da agricultura podem ser utilizadas como biofertilizantes, bioestimuladoras da germinação de semente, biopesticidas e bioinsetisidas. Para estudar experimentalmente o uso da microalga Chlorella sorokiniana na germinação de sementes, é necessário obter informações na literatura sobre as metodologias de aplicação de microalgas em experimentos de campo que visem este processo. O presente trabalho teve como objetivo coletar informações por meio de uma revisão de literatura, sobre as metodologias e formas de aplicação das microalgas na germinação de sementes. O trabalho de revisão foi realizado na base de dados do Google Acadêmico com os seguintes termos de busca avançada: *seeds germination and biostimulant agent and Chlorella microalgae* -wastewater, nos anos de 2018 a 2022. Foram encontrados 164 artigos científicos dentro da temática estudada e foram selecionados somente aqueles trabalhos que apresentavam em suas metodologias as informações sobre a aplicação de microalgas em experimentos de campo e germinação de sementes, totalizando 5 artigos. As microalgas comprovadamente apresentam efeitos positivos na germinação de sementes de feijão, agrião, beterraba, tomate e pepino. Contudo é evidente a necessidade de se investir em pesquisas que considerem as diferentes variáveis nesta ação bioestimuladora, como espécies de microalgas, tipo de extratos (cultura inteira, sobrenadante, biomassa seca ou úmida), extração dos compostos bioativos da microalga, além de quantidade e método de aplicação. Palavras-chave: Chlorella sorokiniana. Agricultura Sustentável. Compostos Bioativos. Métodos de Extração. Abstract Microalgae have several biotechnological applications and in agriculture it can be used as biofertilizers, seed germination biostimulators, biopesticides and bioinsecticides. In order to study the use of microalgae Chlorella sorokiniana in seed germination, it is necessary to obtain information in the literature regarding methodologies for applying microalgae in field experiments. The present work aimed to collect information through a literature review, on methodologies and forms of microalgae application in seed germination. The review was carried out at Google Scholar database using the keywords: *seeds germination and biostimulant agent and Chlorella microalgae* -wastewater, from 2018 to 2022. 164 scientific articles were found but only studies that presented information about microalgae application in field experiments and seed germination were selected, totalizing 5 articles. Microalgae showed positive effects on germination of beans, watercress, beetroot, tomato and cucumber seeds. However, it is evident the need to invest in research that considers different variables in biostimulating action, such as microalgae species, type of extracts (whole culture, supernatant, dry or wet biomass), extraction of bioactive compounds, in addition to quantity and application method. Keywords: Chlorella sorokiniana. Sustainable Agriculture. Bioactive Compounds. Extraction Methods.
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Fernandes, Tomásia, and Nereida Cordeiro. "Microalgae as Sustainable Biofactories to Produce High-Value Lipids: Biodiversity, Exploitation, and Biotechnological Applications." Marine Drugs 19, no. 10 (October 14, 2021): 573. http://dx.doi.org/10.3390/md19100573.
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Microalgae are often called “sustainable biofactories” due to their dual potential to mitigate atmospheric carbon dioxide and produce a great diversity of high-value compounds. Nevertheless, the successful exploitation of microalgae as biofactories for industrial scale is dependent on choosing the right microalga and optimum growth conditions. Due to the rich biodiversity of microalgae, a screening pipeline should be developed to perform microalgal strain selection exploring their growth, robustness, and metabolite production. Current prospects in microalgal biotechnology are turning their focus to high-value lipids for pharmaceutic, nutraceutic, and cosmetic products. Within microalgal lipid fraction, polyunsaturated fatty acids and carotenoids are broadly recognized for their vital functions in human organisms. Microalgal-derived phytosterols are still an underexploited lipid resource despite presenting promising biological activities, including neuroprotective, anti-inflammatory, anti-cancer, neuromodulatory, immunomodulatory, and apoptosis inductive effects. To modulate microalgal biochemical composition, according to the intended field of application, it is important to know the contribution of each cultivation factor, or their combined effects, for the wanted product accumulation. Microalgae have a vital role to play in future low-carbon economy. Since microalgal biodiesel is still costly, it is desirable to explore the potential of oleaginous species for its high-value lipids which present great global market prospects.
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Gonzalez-Bashan, Luz E., Vladimir K. Lebsky, Juan P. Hernandez, Jose J. Bustillos, and Yoav Bashan. "Changes in the metabolism of the microalga Chlorella vulgaris when coimmobilized in alginate with the nitrogen-fixing Phyllobacterium myrsinacearum." Canadian Journal of Microbiology 46, no. 7 (July 1, 2000): 653–59. http://dx.doi.org/10.1139/w00-041.
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In an agroindustrial wastewater pond, a naturally occurring unicellular microalga, Chlorella vulgaris, was closely associated with the terrestrial plant-associative N2-fixing bacterium Phyllobacterium myrsinacearum. When the two microorganisms were artificially coimmobilized in alginate beads, they shared the same internal bead cavities, and the production of five microalgal pigments increased, but there were no effects on the number of the cells or the biomass of the microalga. The association, however, reduces the ability of C. vulgaris to remove ammonium ions and phosphorus from water. The bacterium produced nitrate from ammonium in synthetic wastewater with or without the presence of the microalga, and fixed nitrogen in two culture media. Our results suggest that interactions between microalgae and associative bacteria should be considered when cultivating microalgae for wastewater treatment.Key words: alginate, bacterial immobilization, microalgae, nitrogen fixation, Phyllobacterium, wastewater treatment.
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Ajala, E. O., M. A. Ajala, G. S. Akinpelu, and V. C. Akubude. "Cultivation and Processing of Microalgae for Its Sustainability as a Feedstock for Biodiesel Production." Nigerian Journal of Technological Development 18, no. 4 (February 9, 2022): 322–43. http://dx.doi.org/10.4314/njtd.v18i4.8.
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Microalgae are becoming sustainable alternative feedstocks to food crops for biodiesel production which can also solve the problems associated with the use of fossil fuels. However, several challenges about microalgae’s cultivation, harvesting, pre-treatment and extraction processes as well as the technology of biodiesel production affect its sustainability. This study proffers solutions to these challenges and recommended that hybrid culture systems with genetically engineered microalgal species would overcome the challenges of cultivation. The coagulation/flocculation method was adjudged the best harvesting process of the microalgae for its sustainability for biodiesel production. The pre-treatment by ultrasound coupled with enzymatic extraction was suggested best, due to their numerous advantages over other methods. A novel integrated ultrasound-enzyme-enzyme in-situ pre-treatment-extraction-transesterification design is considered a sustainable approach to utilising microalgae biomass for biodiesel production. The study concludes that the microalgae biomass is more than sufficient to meet the global energy demand and can be economically harnessed as a sustainable feedstock for biodiesel production.
HIGHLIGHTS
•Microalgae contain sufficient characteristics for their sustainability for biodiesel production.• Implementation of genetic strategies of microalgal species by cultivating in a hybrid system is the key to microalgae sustainability.• Harvesting of microalgae by coagulation/flocculation method would promote its efficient lipid recovery.• Microalgae are novel feedstocks with a rigid cell wall, its lipid extraction requires the use of effective and efficient pre-treatment.• The ultrasound-enzymatic extraction and enzymatic transesterification in an in-situ process can sustainably utilise microalgae biomass for biodiesel production.
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Journal, Baghdad Science. "Microalgae Chlorella Vulgaris Harvesting Via Co-Pelletization with Filamentous Fungus." Baghdad Science Journal 15, no. 1 (March 4, 2018): 31–36. http://dx.doi.org/10.21123/bsj.15.1.31-36.
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The objective of this study was to progress another method for coagulation/flocculation of the microalga Chlorella vulgaris via pellet-forming of the fungal species Aspergillus niger which was isolated from municipal wastewater mud and the facultative heterotrophic microalga "C.vulgaris was used. The main factors studies were spore inoculums, organic carbon concentration in medium as well as pH variation which had considerably positive effects on microalgae/fungi co-pelletization formation. The process parameters are an inoculum1×104 spores/ML, 15 g/l sucrose as carbon source and pH ranged from 5 - 7.0 were found optimal for efficient microalgae/fungi co-pelletization formation. For autotrophic growth, when pH of culture broth was adjusted to 5.0 -7.0 with organic carbon addition (15 g/L sucrose), almost complete harvesting efficiency of the microalga was achieved. Furthermore, it was observed that diameter and the concentration of microalgae/fungi pellets were pretentious by the shaker rotation. The new harvesting technology established in this study will decrease the microalga harvesting cost and will be possible to adapt this technique to all microalgal species as an alternative to other old-style harvesting approaches.
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Wang, Hui, Haywood D. Laughinghouse, Matthew A. Anderson, Feng Chen, Ernest Willliams, Allen R. Place, Odi Zmora, Yonathan Zohar, Tianling Zheng, and Russell T. Hill. "Novel Bacterial Isolate from Permian Groundwater, Capable of Aggregating Potential Biofuel-Producing Microalga Nannochloropsis oceanica IMET1." Applied and Environmental Microbiology 78, no. 5 (December 22, 2011): 1445–53. http://dx.doi.org/10.1128/aem.06474-11.
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ABSTRACTIncreasing petroleum costs and climate change have resulted in microalgae receiving attention as potential biofuel producers. Little information is available on the diversity and functions of bacterial communities associated with biofuel-producing algae. A potential biofuel-producing microalgal strain,Nannochloropsis oceanicaIMET1, was grown in Permian groundwater. Changes in the bacterial community structure at three temperatures were monitored by two culture-independent methods, and culturable bacteria were characterized. After 9 days of incubation,N. oceanicaIMET1 began to aggregate and precipitate in cultures grown at 30°C, whereas cells remained uniformly distributed at 15°C and 25°C. The bacterial communities in cultures at 30°C changed markedly. Some bacteria isolated only at 30°C were tested for their potential for aggregating microalgae. A novel bacterium designated HW001 showed a remarkable ability to aggregateN. oceanicaIMET1, causing microalgal cells to aggregate after 3 days of incubation, while the total lipid content of the microalgal cells was not affected. Direct interaction of HW001 andN. oceanicais necessary for aggregation. HW001 can also aggregate the microalgaeN. oceanicaCT-1,Tetraselmis suecica, andT. chuiias well as the cyanobacteriumSynechococcusWH8007. 16S rRNA gene sequence comparisons indicated the great novelty of this strain, which exhibited only 89% sequence similarity with any previously cultured bacteria. Specific primers targeted to HW001 revealed that the strain originated from the Permian groundwater. This study of the bacterial communities associated with potential biofuel-producing microalgae addresses a little-investigated area of microalgal biofuel research and provides a novel approach to harvest biofuel-producing microalgae by using the novel bacterium strain HW001.
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Baldisserotto, Costanza, Sara Demaria, Ornella Accoto, Roberta Marchesini, Marcello Zanella, Linda Benetti, Francesco Avolio, Michele Maglie, Lorenzo Ferroni, and Simonetta Pancaldi. "Removal of Nitrogen and Phosphorus from Thickening Effluent of an Urban Wastewater Treatment Plant by an Isolated Green Microalga." Plants 9, no. 12 (December 18, 2020): 1802. http://dx.doi.org/10.3390/plants9121802.
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Microalgae are photosynthetic microorganisms and are considered excellent candidates for a wide range of biotechnological applications, including the removal of nutrients from urban wastewaters, which they can recover and convert into biomass. Microalgae-based systems can be integrated into conventional urban wastewater treatment plants (WW-TP) to improve the water depuration process. However, microalgal strain selection represents a crucial step for effective phytoremediation. In this work, a microalga isolated from the effluent derived from the thickening stage of waste sludge of an urban WW-TP was selected and tested to highlight its potential for nutrient removal. Ammonium and phosphate abatements by microalgae were evaluated using both the effluent and a synthetic medium in a comparative approach. Parallelly, the isolate was characterized in terms of growth capability, morphology, photosynthetic pigment content and photosystem II maximum quantum yield. The isolated microalga showed surprisingly high biomass yield and removal efficiency of both ammonium and phosphate ions from the effluent but not from the synthetic medium. This suggests its clear preference to grow in the effluent, linked to the overall characteristics of this matrix. Moreover, biomass from microalgae cultivated in wastewater was enriched in photosynthetic pigments, polyphosphates, proteins and starch, but not lipids, suggesting its possible use as a biofertilizer.
Dissertations / Theses on the topic "Microalgae"
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Latil, de Ros Derek. "Microalgae as a new source of chitosans." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/402113.
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Chitosans are a family of linear polysaccharides generally obtained from the chemical deacetylation of chitin derived from crustacean shells that have been reported to have a wide range of bioactivities. However, the development of products taking advantage of these bioactivities has lagged behind expectations. The historic main reason is the poor reproducibility of the biological effects of chitosans due to a harsh chemical deacetylation process that impairs the structure of the polysaccharides inducing variability. Another reason is the immunologic responses that these polymers may produce in the presence of traces of crustacean proteins. It is therefore necessary to gather chitosans from other non-animal sources using a more environmentally friendly and reproducible process. Publications have commented that some microalgae species might contain chitin and even chitosan in their cell walls. Hence, in order to confirm these hypotheses, a screening method has been developed to detect each of these polymers specifically amongst the wide diversity of microalgae species of Greenaltech’s library. Thanks to this screening method, natural chitins and chitosans have been found in several genera. The methodology has been validated with the extraction and physicochemical characterization of chitins and chitosans from Chlorella, something that, to our knowledge, had never been done before. At the same time, the enzymatic deacetylation process behind the natural production of chitosan in Chlorella has been studied emphasizing the identification of active chitin deacetylases. Finally, as part of an exploratory biofunctional study of microalgal chitosans, the antimicrobial, wound healing and nanocapsule-forming properties have been analyzed.
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Carbonell, Chacón Sergi. "Microalgae cultivation in view of resource and energy recovery." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/669859.
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El rabdomiosarcoma (RMS) és el sarcoma de parts toves més comú en la infància i el seu origen rau en les cèl·lules embrionàries precursores del múscul esquelètic. Histològicament se subdivideix en dos tipus: l'embrionari (RMSe) i l'alveolar (RMSa), diferint en presentació clínica, pronòstic i resposta a la teràpia, i és el RMSa el que presenta pitjor pronòstic. El neuroblastoma (NBL) és el tumor sòlid extracranial més habitual en la infància i el tercer càncer pediàtric més recurrent. Representa un 15% de les morts pediàtriques per càncer. Hi ha diversos factors que determinen l'afectació del tumor: l'edat al moment del diagnòstic, l'estadi, alteracions cromosòmiques, la histologia i l'estat de l'oncogèn N-MYC.
La supervivència tant del RMS com del NBL se situa al 70%, però aquesta es redueix fins al 30% en els casos de RMS amb malaltia metastàtica i recidiva, i fins al 20% en els casos de NBL d'alt risc. Aquests casos s'associen a la disseminació del tumor a causa de la metàstasi, quan els tractaments regulars no són efectius. És en aquest context on existeix la necessitat d'estudi dels factors que regulen el procés metastàtic per tal d'identificar noves dianes terapèutiques i així millorar la supervivència d'aquest grup de pacients.
Les integrines són receptors transmembrana cel·lulars amb capacitat de transmetre senyal de l'exterior a l'interior de la cèl·lula i viceversa, que en modifiquen la plasticitat, adhesió i invasió cel·lular i estan implicades en processos patològics com la metàstasi. Anteriorment a aquesta tesi doctoral, el nostre grup d'investigació va suggerir per primera vegada la integrina α9β1 com una proteïna clau en la invasió de les cèl·lules de RMS. En aquesta tesi doctoral es demostra el paper de la integrina α9β1 en la invasió del RMS tant in vitro com in vivo mitjançant la seva inhibició genètica. Es mostra per primera vegada el paper del miR-7 i el miR-324 com a reguladors de la integrina α9β1. També es descriu com l'expressió de la integrina α9β1 en els tumors de RMS resulta en una tendència a una menor supervivència dels pacients, i posicionen la integrina α9β1 com a un marcador de mal pronòstic en el RMS.
El caràcter invasiu de la integrina α9β1 es demostra també en el NBL, on l'expressió de la proteïna en les seves línies cel·lulars és molt elevada i contundent.
S'ha dissenyat molècules blocadores contra la integrina α9β1 a partir d'un dels seus múltiples lligands, tot dirigint el treball cap a una recerca translacional per intentar cobrir les necessitats de la clínica en el tractament del RMS i el NBL. Els inhibidors seleccionats presenten efectes antiinvasius en les línies cel·lulars de RMS i NBL positives per la integrina α9β1. S'ha dut a terme un model murí de metàstasi de RMS amb l'administració dels dos inhibidors més prometedors. Un d'ells ha demostrat ser efectiu in vivo, en el qual s'ha observat un retard en l'aparició de metàstasi i una menor incidència de metàstasi comparat amb el grup control.
En resum, en aquesta tesi doctoral es descriu el paper de la integrina α9β1 en el RMS i el NBL i es demostra el rol d'aquesta en la metàstasi. A més, es desenvolupa un nou inhibidor contra la integrina α9β1, que presenta un fort efecte antiinvasiu tant in vitro com in vivo. Així doncs, es proposa la integrina α9β1 com una nova diana terapèutica contra el procés metastàtic en el càncer pediàtric.Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in childhood and it is derived from primitive mesenchyme that retained its capacity for skeletal muscle differentiation. Histologically, it can be divided into two main subtypes: embryonal rhabdomyosarcoma (RMSe) and alveolar rhabdomyosarcoma (RMSa), with differing in clinical presentation, prognosis and responses to therapy, with RMSa having the worst prognosis. Neuroblastoma (NBL) is the most common extracranial solid tumor in childhood and the third most recurrent pediatric cancer. It accounts for around 15% of all pediatric oncology deaths. Several factors determine tumor involvement: the age at the time of diagnosis, the stage, chromosomal disorders, histology and the state of the N-MYC oncogene. Survival rates for RMS and NBL are 70%, but fall to 30% in cases of metastatic RMS and recurrence, and to 20% in cases of high risk NBL. These cases are associated with the dissemination of the tumor due to metastasis, when regular treatments are not effective. It is in this context where there is a need to study the factors that regulate the metastatic process in order to identify new therapeutic targets and thus improve the survival of this group of patients. Integrins are cellular transmembrane receptors capable of transmitting signal from the outside to the inside of the cell and viceversa. They can modify plasticity, adhesion and cell invasion and are involved in pathological processes such as metastasis. Prior to this doctoral thesis, our research group suggested α9β1 integrin as a key protein in the invasion of RMS cells for the first time. In this work, we demonstrate the role of α9β1 integrin in invasion both in vitro and in vivo through its genetic inhibition. The role of miR-7 and miR-324 as regulators of the α9β1 integrin is shown for the first time. How the expression of α9β1 integrin in RMS tumors results in a tendency for poorer survival for patients is also described, and α9β1 integrin is positioned as a poor prognostic marker in the RMS. The invasiveness of α9β1 integrin is also demonstrated in the NBL, where there is high protein expression in its cell lines. Blocking molecules have been designed against α9β1 integrin from one of its multiple ligands, and work directed towards translational research in order to cover the clinical needs of the treatment of RMS and NBL. Selected inhibitors have antiinvasive effects on α9β1 integrin RMS and NBL cell lines. A murine metastases model of RMS has been performed with the administration of the two most promising inhibitors. One of these has been shown to be effective in vivo, with a delay in the appearance of metastasis and a lower incidence of metastasis compared to the control group. To sum up, this thesis describes the role of α9β1 integrin in the RMS and NBL and demonstrates its role in metastasis. In addition, a new inhibitor is developed against α9β1 integrin, which has a strong antiinvasive effect both in vitro and in vivo. Accordingly, α9β1 integrin is proposed as a new therapeutic target against the metastatic process in pediatric cancer.
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Haponska, Monika. "Biorefining of microalgae: from harvesting to biofuel production." Doctoral thesis, Universitat Rovira i Virgili, 2018. http://hdl.handle.net/10803/663366.
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Aquesta tesi es centra en la modernització del procés de bio-refinat de microalgues mitjançant tecnologia de
membrana. El projecte busca l'optimització de: recol·lecció, ruptura cel·lular, fraccionament de carbohidrats, proteïnes
i lípids i desenvolupament d'un reactor de membrana catalítica per a la transesterificació per obtenir biodièsel. La
reducció de costos es pot aconseguir trobant solucions més barates i millors per a cada pas.
En la primera etapa, es va realitzar la filtració utilitzant membranes polimèriques d'ABS de fabricació pròpia, així com
altres disponibles comercialment, per comprovar el seu rendiment en la deshidratació de microalgues. Aquest estudi
inclou la preparació i caracterització de membranes d'ABS usant diferents tècniques. A més, es va realitzar la
comparació de dos mètodes de filtració, flux creuat i dinàmic per comparar la viabilitat de les membranes afectades
per embrutiment.
En la segona etapa, es va realitzar la deshidratació a escala pilot de dues espècies de microalgues, Chlorella
sorokiniana i Dunaliella tertiolecta per sedimentació i filtració dinàmica. L'objectiu va ser reduir els costos de
deshidratació de microalgues amb un cost menor al de centrifugació. bio-refinat de microalgues aigües avall.
En la quarta etapa, es va realitzar la comparació de nous reactors de membrana catalítica i inert per a la producció de
biodièsel amb òxid d'estronci com a catalitzador heterogeni. Els principals objectius van ser identificar un catalitzador
adequat, triar la tècnica d'immobilització adequada, establir la membrana amb la mida de porus adequat i controlar la
reacció i el procés de separació.microalgues amb diferents característiques de paret cel·lular. L'objectiu d'aquest treball va ser millorar el procés de bio-refinat de microalgues aigües avall.
En la quarta etapa, es va realitzar la comparació de nous reactors de membrana catalítica i inert per a la producció de
biodièsel amb òxid d'estronci com a catalitzador heterogeni. Els principals objectius van ser identificar un catalitzador
adequat, triar la tècnica d'immobilització adequada, establir la membrana amb la mida de porus adequat i controlar la
reacció i el procés de separació.Esta tesis se centra en la modernización del proceso de biorefinado de microalgas mediante tecnología de membrana. El proyecto busca la optimización de: recolección, ruptura celular, fraccionamiento de carbohidratos, proteínas y lípidos y desarrollo de un reactor de membrana catalítica para la transesterificación para obtener biodiesel. La reducción de costos se puede lograr encontrando soluciones más baratas y mejores para cada paso. En la primera etapa, se realizó la filtración utilizando membranas poliméricas de ABS de fabricación propia, así como otras disponibles comercialmente, para comprobar su rendimiento en la deshidratación de microalgas. Este estudio incluye la preparación y caracterización de membranas de ABS usando diferentes técnicas. Además, se realizó la comparación de dos métodos de filtración, flujo cruzado y dinámico para comparar la viabilidad de las membranas afectadas por ensuciamiento. En la segunda etapa, se realizó la deshidratación a escala piloto de dos especies de microalgas, Chlorella sorokiniana y Dunaliella tertiolecta por sedimentación y filtración dinámica. El objetivo fue reducir los costos de deshidratación de microalgas con un costo menor al de centrifugación. En la tercera etapa, se estudió la disrupción celular y el fraccionamiento para la recuperación de lípidos, azúcares y proteínas usando explosión de vapor, flujo cruzado y filtración dinámica de membrana. Se probaron varias especies de microalgas con diferentes características de pared celular. El objetivo de este trabajo fue mejorar el proceso de biorrefinado de microalgas aguas abajo. En la cuarta etapa, se realizó la comparación de nuevos reactores de membrana catalítica e inerte para la producción de biodiesel con óxido de estroncio como catalizador heterogéneo. Los principales objetivos fueron identificar un catalizador adecuado, elegir la técnica de inmovilización adecuada, establecer la membrana con el tamaño de poro adecuado y controlar la reacción y el proceso de separación.
his thesis focuses on the modernization of the downstream process of microalgae biorefining by membrane technology. The project concerns the optimization of: harvesting, cell disruption, carbohydrates, proteins and lipids fractionation and development of catalytic membrane reactor for transesterification to obtain biodiesel. Cost reduction of the overall process can be achieved by finding cheaper solutions for each step. In the first stage the filtration using own-made ABS polymeric membranes as well as the commercially available ones was run to check their performance for microalgae dewatering. This study included ABS membranes preparation and characterization using different techniques. Also, the comparison of two filtration methods, cross-flow and dynamic was performed to compare the viability of membranes affected by a fouling and a cake formation. In a second stage, the pilot scale dewatering of two microalgae specie, Chlorella sorokiniana and Dunaliella tertiolecta by sedimentation followed by dynamic filtration was performed. The objective of the combined process was to reduce microalgae dewatering costs since sedimentation offers a very cheap operation and membrane filtration offers total rejection with high final concentrations at a lower cost than centrifugation. In a third stage cell disruption and fractionation for lipids, sugars and proteins recovery was studied. Acid-catalysedT
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Vidotti, Annamaria Dória Souza. "Cultivo heterotrófico axênico de Chlorella vulgaris = inibição por substrato = Axenic heterotrophic cultivation of Chlorella vulgaris : substrate inhibition." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266695.
Full textAbstract:
Orientador: Telma Teixeira FrancoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química.
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Resumo: Rotas heterotróficas a partir de microalgas apresentam ganhos significativos de produtividade em biomassa quando comparadas aos sistemas fotossintéticos convencionais, estando a glicose e o acetato entre as fontes de carbono mais comuns desse tipo de cultivo. Neste contexto, o objetivo do presente estudo foi desenvolver cultivos heterotróficos axênicos para a microalga Chlorella vulgaris, utilizando a glicose e o acetato de sódio como fontes de carbono exógeno, avaliando o efeito de inibição por substrato, bem como a modelagem dos perfis de crescimento de biomassa e consumo de substrato. A influência da concentração inicial de substrato na produção de biomassa pela C. vulgaris foi investigada, sendo obtidas cinéticas de crescimento do microrganismo submetido a concentrações iniciais de glicose entre 2 e 100 g.L-1, e de acetato de sódio, entre 2 e 20 g.L-1. Foi verificado que a concentração inicial de substrato influenciou significativamente o rendimento celular final, e que apesar dos dois substratos avaliados terem se mostrado fontes de carbono adequadas, a utilização de maiores concentrações iniciais, 100 g.L-1 e 20 g.L-1 de glicose e acetato de sódio, respectivamente, acarretaram na inibição do crescimento da C. vulgaris. Os modelos matemáticos testados representaram adequadamente a cinética de inibição, sendo que os resultados indicaram que a concentração ótima de glicose para o cultivo heterotrófico da C. vulgaris foi 5,8 ± 0,3 g.L-1 e de acetato de sódio foi 3,5 ± 0,2 g.L-1. Os resultados evidenciaram ainda que os procedimentos adotados no controle da contaminação foram efetivos para a manutenção da axenia dos cultivos. Pela comparação do desempenho cinético, foi constatada uma superioridade (maior que 50%) da glicose como substrato em comparação com o acetato de sódio. E no estudo de aumento de produtividade de biomassa para cultivos com acetato, foi obtido um aumento de 70% neste parâmetro com a batelada alimentada, e uma concentração final de biomassa 2,5 vezes maior do que a melhor concentração celular alcançada em shaker
Abstract: Heterotrophic microalgal routes show significant productivity gains in biomass when compared with the conventional photosynthetic systems, being glucose and acetate among the most common carbon sources such in this kind of cultivation. In this context the objective of this study was to develop axenic cultures for heterotrophic microalgae Chlorella vulgaris using glucose and sodium acetate as exogenous carbon sources, evaluating the effect of substrate inhibition, as well as the modeling of the biomass growth profiles and substrate consumption. The influence of the initial substrate concentration in the biomass production by C. vulgaris was investigated, being obtained kinetics growth of the microorganism subjected to initial glucose concentrations between 2 and 100 g/L-1, and sodium acetate between 2 and 20 g/L-1. It was found that the initial substrate concentration significantly affected the final cell yield and that although the two have been shown to be tested substrates carbon sources suitable, the use of larger initial concentrations of 100 and 20 g.L-1 of glucose and sodium acetate, respectively, resulted in inhibiting the growth of C. vulgaris. The mathematical models tested represented adequately the kinetics of inhibition, and the results indicated that the optimum concentration of glucose to heterotrophic cultivation of C. vulgaris is 5,8 ± 0,3 g.L-1 and for the sodium acetate this value is 3,5 ± 0,2 g.L-1. The results showed also that the procedures used in contamination control have been effective for the maintenance of the axenic of crops. By comparing the performance, kinetic superiority was observed (more than 50%) for the systems using glucose as substrate in comparison with the systems using sodium acetate. Finally, in the study of increasing of productivity of biomass for crops with acetate, was obtained a 70% increase in this parameter with the fed batch operation, and a final biomass concentration 2.5 times greater than the best cell concentration achieved in shake flasks
Mestrado
Desenvolvimento de Processos Químicos
Mestra em Engenharia Química
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Hom, Díaz Andrea. "Degradation of pharmaceutical compounds by microalgae: photobioreactor wastewater treatment, biomass harvesting and methanization." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/390962.
Full textAbstract:
Els contaminants emergents (ECs) són un ampli grup de compostos orgànics detectats
en diversos compartiments ambientals que degut a la seva presència en el medi
ambient i la seva difícil degradació han aixecat un gran interès en la comunitat
científica. Tot i que la seva concentració normalment està compresa entre els ng/L i els
μg/L, poden representar una amenaça per a la salut humana i el medi ambient ja que
són excretats per la orina i els fems, ja sigui en forma de compost actiu o com a
metabòlit, ja que no són completament assimilats. D’entre tots els emergents, els
compostos disruptors endocrins (EDCs) i els principis actius dels fàrmacs (PhACs)
generen especial preocupació. Està àmpliament acceptat que la seva principal font
d’entrada al medi ambient és a través dels efluents de les plantes depuradores
(WWTP), on els tractaments convencionals de llots actius no són capaços de
degradar-ne la majoria, sent capaços d’arribar a les aigües superficials, subterrànies i,
posteriorment, a l’aigua potable. Per tant, s’han de buscar tractaments alternatius. Un
d’aquests tractaments podria ser l’ús de les microalgues aprofitant la seva capacitat
pel tractament d’aigües residuals, eliminant els nutrients de l’aigua residual i la seva
posterior conversió en biocombustibles.
Aquesta tesi avalua diferents aspectes relacionats amb la degradació de contaminants
emergents i tractament d’aigües amb microalgues. A més de l’estudi d’un dels
principals colls d’ampolla dels sistemes de microalgues, la collita, que té l’avantatge de
clarificar l’aigua residual tractada i concentrar la biomassa algal per a la seva conversió
a biogàs. Tant, cultius purs com efluents de microalgues s’han considerat.
Primerament, s’ha estudiat la degradació individual de dos compostos estrogènics.
Aquests dos compostos estrogènics s’han introduït recentment a la llista de
substàncies prioritàries de la directiva de l’aigua: 17α-etinileestradiol (EE2) i 17β-
estradiol (E2). La seva degradació s’ha monitoritzat a partir dels cultius purs de
Chlamydomonas reinhardtii i Pseudokirchneriella subcapitata a nivell de laboratori. Per
tal d’obtenir més informació sobre els mecanismes de degradació s’ha fet la
identificació dels productes de transformació.
A més, la degradació d’una mescla de 10 fàrmacs (9 antibiòtics i un antidepressiu) s’ha
avaluat en cultius purs de microalgues a escala laboratori. S’ha realitzat la identificació
dels productes de transformació de tres PhACs seleccionats. Posteriorment, un dels
antibiòtics, la ciprofloxacina, s’ha analitzat. Els seus mecanismes d’eliminació han
estat estudiats en sistemes algals, tant en reactors a escala laboratori com en escala
pilot.
Per altra banda, s’ha dissenyat un fotobioreactor (PBR) d’algues tractant aigua residual
urbana i en operació durant 6 mesos. S’ha monitoritzat el seu seguiment i s’han provat
diferents condicions d’operació. A més, un cop a l’estat estacionari l’eliminació de
PhACs s’ha estimat i s’ha caracteritzat la població microbiana. També s’ha estudiat
l’eliminació del compost estrogènic E2 en el PBR.
En aquesta tesi també es remarca la importància de la collita de microalgues. Tres
tècniques de collita (i.e., sedimentació natural, coagulació-floculació i la tècnica
innovadora de co-pel·letització utilitzant el fong Trametes versicolor) s’han aplicat en
dos efluents reals de microalgues i a una suspensió pura de Chlamydomonas
reinhardtii.
Finalment, s’ha dut a terme la metanització de biomassa exhausta. Abans del procés
de digestió anaeròbia, per tal de solubilitzar la paret cel·lular les algues han estat
sotmeses a un pretractament enzimàtic. S’han provat enzims específics i no
específics, així com l’efecte combinat utilitzant una mescla d’enzims. Aquest estudi es
completa amb la valorització de biomassa fúngica que prové del tractament d’efluents.Emerging contaminants (ECs) are a wide range of organic compounds detected in many environmental compartments that have raised an increasing interest in the scientific community due to their ubiquitous presence in the environment and their difficult degradation. Even though their environmental concentration is usually in the range of ng/L to μg/L, they still represent a threat to human health and environment since they are excreted with urine and faeces either as active substances or metabolites, because they are not completely assimilated. Among emerging contaminants, endocrine disrupting compounds (EDCs) and pharmaceutical active compounds (PhACs) are of major concern. It is widely accepted that the main source to the environment are the effluents of wastewater treatment plants (WWTP), where conventional activated sludge treatments are not able to degrade most of them being able to reach surface, groundwater and subsequently, drinking water. Therefore, alternative treatments should be found. One of those alternatives might be the use of microalgae by taking advantage of their capacity for wastewater treatment removing the nutrients contained in the wastewater and further microalgal biomass conversion into biofuels. The present thesis assesses different factors related to microalgal degradation of emerging contaminants and wastewater treatment. As well as the study of one of the major bottlenecks on microalgal systems, the harvesting, which has the advantage to clarify the treated wastewater and concentrate the microalgal biomass for further biogas production. Pure microalgal cultures and real microalgal effluents have been considered. First of all, individual degradation of two estrogenic compounds has been studied. The two estrogenic compounds evaluated have been recently incorporated in the priority substances in the Water Framework Directive: 17α-ethinylestradiol (EE2) and 17β- estradiol (E2). Their degradation by Chlamydomonas reinhardtii and Pseudokirchneriella subcapitata pure cultures at laboratory scale conditions has been monitored. To obtain further insights in the mechanism of degradation the transformation products have been identified. Moreover, the removal of a mixture of 10 PhACs (9 antibiotics and an antidepressant) has also been assessed in pure microalgal cultures at laboratory scale conditions. Transformation products from three chosen PhACs have been identified. One of the antibiotics, ciprofloxacin, was further evaluated. The removal mechanisms have been studied in real algal ponds in both, laboratory and pilot scale reactors. On the other hand, an algal photobioreactor (PBR) treating urban wastewater has been designed and operated during 6 months. Its performance has been monitored and different operating conditions have been tested. Furthermore, PhACs removal has been evaluated during the steady state and microbial diversity has been identified. The estrogenic compound E2 removal in the PBR has been studied. The importance of microalgal harvesting has been highlighted in the thesis. Three different harvesting techniques (i.e., natural sedimentation, coagulation-flocculation and the novel technique of co-pelletization using Trametes versicolor fungus) have been evaluated using two real microalgal effluents and a pure Chlamydomonas reinhardtii suspension. Finally, methanization of exhausted biomass has been conducted. Prior the anaerobic digestion process microalgal biomass has been submitted to an enzymatic pretreatment for its cell wall solubilisation. Specific and non-specific enzymes have been tested as well as the synergistic effects between an enzymatic mixture. The study is completed valorising fungal biomass coming from the treatment of effluents.
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Brain, Chelsea Marie. "Bioprocessing in microalgae." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/3695.
Full textAbstract:
This thesis is a portfolio of three projects carried out with Scottish Bioenergy Ltd, in the area of microalgae biotechnology. The first small project saw the development of a rapid, simple and relatively low-cost technique based on UV absorbance for measurement of nitrate in two common freshwater and saltwater growth media. The test was successfully demonstrated in batches of Chlorella, measuring nitrate concentration as low as 40 μM and requiring only a 2 mL sample. The second large project investigated the use of a narrow spectrum Light Emitting Diode (LED) with a maximum wavelength (λmax) of 680 nm for the production of the high-value pigment phycocyanin in Arthrospira (Spirulina). The LEDs produced a substantial over 250 % increase in phycocyanin yield with no significant difference in growth rate in comparison to standard white LEDs, initially requiring an extended photoacclimation period. Although photobioreactor (PBR) systems incorporating the λmax 680 nm would require increased investment in capital and operational expenditure, particularly relating to increased LED cooling requirements, increased product yield and profitability makes a powerful case for switching to longer wavelength red LEDs. The third project was a feasibility study for the use of directed microevolution to generate a non-genetically modified copper-tolerant Arthrospira strain that may be used in a multi-process PBR system fed with distillery wastewater. Resistance 200-fold the typical optimal medium concentration was achieved. However, the extent of resistance was 3-fold lower than required and the length and unreliability made the process impractical for industrial use in generating resistant Arthrospira strains. The projects provided a methodology to assist the company in future research and development, knowledge on the feasibility of a strain development technique and identified an exciting new business opportunity for production of a high-value product in artificially illuminated PBR systems.
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Abida, Heni. "Characterization of lipid metabolism in the marine diatom Phaeodactylum tricornutum." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS231.
Full textAbstract:
L’océan domine la surface de notre planète et joue un rôle majeur dans la régulation de notre biosphère. Par exemple, les microorganismes photosynthétiques vivant dans l’océan produisent 50% de l’oxygène que nous respirons tous les ans, et une grande partie de notre alimentation et des ressources minérales en proviennent. En cette époque de crise écologique liée à l’accumulation anthropogénique de gaz à effet de serre dans l’atmosphère, il est impératif de développer des énergies plus durables que les carburants fossiles. Le biodiesel pourrait être une source de carburant viable et durable pour remplacer le pétrodiesel mais jusque-là, nos efforts visant à produire des lipides à base de microalgues se sont essentiellement concentrés sur des algues vertes. Dans cette thèse je propose des méthodes pour mieux caractériser une autre catégorie de microalgue : les diatomées. Les diatomées sont une composante importante du phytoplancton et contribuent 40% de la production marine de biomasse primaire. Les diatomées accumulent des lipides en réponse à la carence en nutriments, et même si elles semblent accumuler tout autant de lipides que les microalgues vertes, les voies métaboliques menant à l’accumulation de lipides sont encore peu connues.Dans cette thèse je décris notre caractérisation du glycerolipidome de la diatomée modèle Phaeodactylum tricornutum ainsi que notre étude du remodelage de lipides suite à la carence d’azote ou de phosphate. Des accessions de P. tricornutum isolées dans différentes régions de l’océan ont aussi été étudiées afin de comparer leurs réponses au stress nutritif. Nous avons trouvé que la réponse métabolique menant à l’accumulation de lipides en carence d’azote ou de phosphate est différente. En effet, la carence en azote semble déclencher le recyclage des galactoglycerolipides chloroplastiques ainsi qu’une augmentation de la biosynthèse de novo d’acides gras, alors que la carence en phosphate est plus sévère car nous avons observé une accumulation plus significative de triacylglycerols ainsi que la déplétion totale des phospholipides. De plus, nous avons observé des réponses au stress différentes entre les accessions de P. tricornutum, et en particulier concernant leur capacité à accumuler des lipides. Nous proposons l’hypothèse que ces différences sont liées à leur aptitude à recycler du carbone issu de molécules de stockage non lipidiques.Des approches génomiques ont permis de nombreuses avancées pour mieux comprendre le métabolisme des lipides de microalgues mais notre compréhension des voies de biosynthèse de lipides chez les diatomées est encore limitée. Il y a eu diverses tentatives de caractérisation de la réponse au stress de carence par approche transcriptomique mais l’étude de ces données est incomplète du fait de l’annotation insuffisante des gènes encodant les voies métaboliques pertinentes. Ainsi, dans cette thèse je décris nos tentatives d’annotation de gènes impliqués dans le métabolisme des lipides de P. tricornutum ainsi que les approches d’ingénierie génétique visant à mieux caractériser certains de ces gènes. J’ai également utilisé notre nouvelle annotation de gènes impliqués dans le métabolisme des lipides pour effectuer une étude comparative de plusieurs transcriptomes de P. tricornutum en conditions de carence trouvés dans la littérature. J’ai ainsi pu produire une liste de gènes potentiellement impliqués dans l’accumulation de lipides. Enfin, nous avons pu utiliser ces données pour aider l’interprétation de données génomiques et transcriptomiques issues de la diatomée oléagineuse Fistulifera solaris afin de mieux comprendre comment elle accumule des quantités importantes de lipides pour des applications dans le secteur des biotechnologies et des bioénergiesThe ocean dominates the surface of our planet and plays a major role in regulating the biosphere. For example, the microscopic photosynthetic organisms living in the ocean provide 50% of the oxygen we breathe every year, and much of our food and mineral resources are extracted from the ocean. In a time of ecological crisis linked to the accumulation of anthropogenic greenhouse gases in the atmosphere, we must investigate more sustainable energies than fossil fuels. Much attention has been given to biodiesel but so far most efforts to efficiently produce triacylglycerols in microalgae have focused on green algae. In this thesis I propose approaches to better understand another type of microalgae that is significantly divergent from green lineages: diatoms. Diatoms are a major phylum of phytoplankton in the ocean and account for 40% of marine primary productivity. While diatoms appear to be at least as effective as green algae for producing lipids, the fatty acid and glycerolipid biosynthetic pathways leading to their production have not yet been well characterized. Therefore, I propose to better characterize these pathways in the model diatom Phaeodactylum tricornutum in order to help unlock the potential of diatoms for lipid-based biotechnological applications.In this thesis, I discuss our attempts to establish a reference for the glycerolipidome of P. tricornutum and of our assessment of the lipid remodeling and accumulation that occurs in response to nitrogen- and phosphorus-starvation. A range of accessions of P. tricornutum isolated from different parts of the ocean were also examined to compare their responses to nutrient deprivation. We found that the metabolic response leading to lipid accumulation in different nutrient-deprived conditions are distinct. Nitrogen-deprivation appears to trigger the recycling of chloroplastic galactoglycerolipids as well as a strong increase in de novo fatty acid synthesis while the response to phosphorus-deprivation was more severe as we observed a higher triacylglycerol pool and the complete depletion of phospholipids. Furthermore, we observed several differences among accessions of P. tricornutum regarding their ability to accumulate triacylglycerol in response to nutrient starvation and propose the hypothesis that these differences are linked to their ability to recycle intracellular carbon from non-lipid storage molecules.Genome-enabled approaches have also allowed significant steps towards elucidating the lipid metabolism of microalgae in the past decade, but our understanding of diatom metabolic pathways is still limited compared to that of other microalgae and higher plants. There have been several attempts to characterize the stress response in P. tricornutum by using transcriptomic approaches but this data is difficult to exploit to its full potential without a better annotation of genes encoding the relevant pathways. Therefore, in this thesis I discuss our attempts to annotate P. tricornutum lipid metabolism genes. Based on this annotation I have attempted to better characterize a selection of genes by genetic engineering and have pursued a comparative study of several published transcriptomes of P. tricornutum in nutrient deprived conditions to produce a list of candidate genes likely to be involved in triacylglycerol accumulation. Finally, we used this data to help interpret genome and transcriptome data of the newly sequenced oleaginous diatom Fistulifera solaris to help understand how it accumulates unusually high amounts of triacylglycerol for applications in the biotechnology and bioenergy industry
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Franco, Acosta Liliana Marcela. "Estudo de fontes de carbono orgânicos no cultivo heterotrófico da microalga Chlorella vulgaris." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266696.
Full textAbstract:
Orientador: Telma Teixeira FrancoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Em cultivos heterotróficos, fontes orgânicas de carbono são utilizadas para fornecer energia e carbono ao micro-organismo. A glicose e uma das fontes mais utilizadas em cultivos de microalgas, gerando elevadas taxas de crescimento. Outras fontes como frutose, xilose, glicerol, sacarose, arabinose também podem ser utilizadas e a escolha entre essas fontes orgânicas e função principalmente das taxas de crescimento e do custo de aquisição. Visando elevadas produtividades e a redução do custo do cultivo heterotrófico da Chlorella vulgaris, diferentes fontes de carbono orgânico foram avaliadas (glicerol, sacarose, frutose e melaço de cana). Os máximos valores de concentração celular, pH e produtividade, foram para a sacarose hidrolisada na concentração inicial de 20 g.L-1 obtidos apos 122 horas de cultivo (5,3g.L-1; 8.80 e 0.040 g.L-1.h-1, respectivamente) e para o melaço de cana hidrolisado na concentração de 30 g.L-1 obtidos apos 60 horas de cultivo (3,92 g.L-1; 8,55 e 0,059 g.L-1.h-1, respectivamente). Glicerol, sacarose e frutose não foram consumidas pelas células. As melhores concentrações de sacarose hidrolisada (20 g.L-1) e melaço de cana hidrolisado (15 g.L-1) foram utilizados em fermentador de 3 L em regime de batelada alimentada, as velocidades especificas de crescimento para o melaço de cana aumentaram apos cada alimentação desde 0,0512 h-1 ate 0,0644 h-1. No entanto, para a sacarose hidrolisada a velocidade diminuiu de 0,0251 h-1 ate 0,0143 h-1. A concentração de lipídeos foi para a sacarose hidrolisada (23,77 %), e (10,72%) para o melaço de cana. Paralelamente, foram analisadas condições de estocagem da microalga Chlorella vulgaris, em ultrafreezer, empregando-se três criopreservantes: glicerol, metanol e DMSO, nas concentrações de 5 e 10%. Os resultados, apos 270 dias de estocagem, indicam que a microalga Chlorella vulgaris não sobrevive nas condições estabelecidas. No entanto, para uma estocagem de ate 180 dias pode-se empregar 10% de glicerol ou 10% de DMSO, necessitando somente 2 repiques da microalga apos o armazenamento para atingir sua velocidade normal de crescimento (0,2686 d-1), velocidade reportada para a microalga sem armazenamento no ultrafreezer
Abstract: In heterotrophic culture, sources of organic carbon are utilized to give energy and carbon to microorganisms. Glucose is one of the main sources utilized in micro algae culture which produces high growing rates. Another sources such as fructose, xylose, glycerol, saccharose and arabinosa, could also be utilized. The function of growing rates and acquisition costs is precisely to help us to choose the best one between these sources. With the idea of getting high productivities and to reduce costs of heterotrophic crops of Chlorella vulgaris, different sources of organic carbon where studied (glycerol, saccharose, fructose and sugar cane honeydew). The highest values of cellular concentration, pH and productivity, were obtain from hydrolyzed saccharose with an initial concentration of 20 g.L-1 after 122 hours of cultivation (5,3g.L-1; 8.80 y 0.040 g.L-1.h-1, respectively). Glycerol, saccharose y fructose were not consumed by the cells. The best concentrations of hydrolyzed saccharose (20 g.L-1) and hydrolyzed sugar cane honeydew (15 g.L-1) were utilized in 3 L fermenters in feed batch. The growing speed of the sugar cane honeydew increased after each feeding from 0,0512 h-1 to 0,0644 h-1. However, the growing speed for hydrolyzed saccharose decreased from 0,0251 h-1 to 0,0143 h-1. The concentration of fat acids for the hydrolyzed saccharose was 23,77 % and for the sugar cane honeydew was 10,72%. Storage conditions in ultrafreezer for the microalgae Chlorella vulgaris were studied at the same time using three different protectants such as glycerol, methanol and DMSO, all of them in 5% and 10% concentrations. The outcomes obtained after 270 days showed that the Chlorella vulgaris microalgae could not survive with the given conditions. However, 10% of glycerol or DMSO could be used in a 180-day storage and only 2 periodic transfer of the microalgae were needed after the storage to obtain the normal growing speed (0.2686 d- 1), which was the reported speed of the microalgae without ultrafreezer storage
Mestrado
Processos em Tecnologia Química
Mestra em Engenharia Química
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Gaignard, Clément. "Criblage, identification et caractérisations physico-chimiques d'exopolysaccharides de microalgues et Cyanobactéries." Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAC067.
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Le principal objectif de cette thèse était d’améliorer les connaissances sur la capacité des microalgues et Cyanobactéries à produire des Exopolysaccharides (EPS). Le criblage effectué sur 166 souches de la Roscoff Culture Collection (RCC) a permis d’identifier 45 nouvelles souches potentiellement productrices d’EPS. Des études biochimiques par Chromatographie Echangeuse d’Anions Haute Performance couplée à un Détecteur Ampérométrique Pulsé (CEAHP-DAP), et par Chromatographie Phase Gaz couplée à de la Spectrométrie de Masse (CPG/SM) ont confirmé la nature polysaccharidique de 20 nouveaux polymères identifiés. Au cours de ce travail, des cultures en Photobioréacteur (PBR) 1,4 et 5 L ont été menées sur quelques souches et de caractériser au plus fin leur EPS (compositions biochimiques et caractéristiques physico-chimiques). Cela a conduit, en autre, à l’identification d’un hétéroxylane issu d’une microalgue Glossomastix. Cet EPS est constitué d’une chaîne principale de β-(1,3)- et β-(1,4)-d-Xylp substituée en positions O-2 et O-3 par diverses chaînes et/ou résidus terminaux tels que d-Xylp-(1→6)-d-Galp, d-Xylp-(1→4)-d-Galp, d-Xylp-(1→3)-d-Galp, Galp-(1⟶SF-Xylp-(1⟶Xylp-(1⟶Glcp-(1⟶.Enfin, des analyses statistiques réalisées sur 81 compositions en monosaccharides d’EPS de microalgues ont permis pour la première fois d’établir un lien entre la composition biochimique et l’appartenance phylogénétique des microalguesThe main objective of this thesis was to improve knowledge on the capacity of microalgae and Cyanobacteria to produce Exopolysaccharides (EPS). Screening carried out on 166 strains from the Roscoff Culture Collection (RCC) made it possible to identify 45 new potentially EPS producers. Biochemical studies using High Performance Anion Exchange Chromatography with a Pulsed Amperometric Detector (HPAEC-PAD), and Gas Chromatography with Mass Spectrometry (GC/MS) confirmed the polysaccharide nature of 20 new identified polymers. During this work, cultures in 1,4 and 5 L Photobioreactors (PBR) were performed on few strains in order to characterize at best their EPS (biochemical compositions and physicochemical characteristics). This word led, in addition, to the identification of a heteroxylan from the microalga Glossomastix. Its EPS consists of a main chain of β-(1,3)- and β-(1,4)-d-Xylp substituted in O-2 and O-3 positions by various chains and/or terminal residues such as d-Xylp-(1→6)-d-Galp, d-Xylp-(1→4)-d-Galp, d-Xylp-(1→3)-d-Galp, Galp-(1⟶SF-Xylp-(1⟶Xylp-(1⟶Glcp-(1⟶. Finally statistical analyzes carried out on 81 monosaccharide compositions of microalgae EPS made it possible for the first time to establish a link between biochemical composition and phylogenetic membership of microalgae
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Bonnefond, Hubert. "Amélioration de microalgues à vocation énergétique par pression de sélection continue." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066719/document.
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Le monde fait face à une crise environnementale sans précédent, induite par l’action toujours plus marquée de l’homme sur son milieu. Depuis le début de l’ère industrielle, l’utilisation massive des énergies fossiles, a provoqué un dérèglement climatique planétaire. Les microalgues offrent la possibilité de produire des biocarburants avec une empreinte carbone réduite mais nécessitent encore de nombreuses améliorations pour être économiquement viables. Une de ces améliorations, à l’instar de l’agriculture moderne, réside dans la sélection de souches plus productives. Dans ce travail de thèse, nous avons développé la sélection par pression continue, consistant à utiliser les processus de l’évolution pour faire émerger des populations d’intérêt.Une première voie explorée a consisté à utiliser la température, paramètre crucial de la croissance des microalgues, comme moteur de sélection. En soumettant une culture à des variations diurnes de température durant une année, nous sommes parvenus à adapter une souche de Tisochrysis lutea à une gamme de températures plus large, la rendant donc plus tolérante aux variations de ce paramètre.La seconde voie a cherché à accroitre la capacité de Cylindrotheca closterium à emmagasiner ou au contraire à mobiliser son azote intracellulaire, propriété physiologiquement liée à sa capacité à produire des lipides. En forçant une population de microalgues à s'adapter à des apports discontinus d'azote (succession d'états de satiété et de carence), il a été possible de sélectionner les individus les plus riches en lipides.Enfin, nous avons modifié l'appareil pigmentaire de Tisochrisis lutea pour la rendre plus transparente à la lumière. En soumettant cette espèce à une succession de chocs lumineux, il a été possible de sélectionner les individus possédant les antennes photosynthétiques les plus petites, permettant une productivité accrueThe world faces an unprecedented environmental crisis, led by the action always more marked with the man on its environment. From the beginning of the industrial era, the massive use of the fossil fuels, caused a global climatic disorder
Books on the topic "Microalgae"
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Posten, Clemens, and Steven Feng Chen, eds. Microalgae Biotechnology. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-23808-1.
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Tamar, Berner, ed. Ultrastructure of microalgae. Boca Raton: CRC Press, 1993.
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D, Cohen Zvi Ph, ed. Chemicals from microalgae. London: Taylor & Francis, 1999.
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Tebbani, Sihem, Filipa Lopes, Rayen Filali, Didier Dumur, and Dominique Pareau. CO2Biofixation by Microalgae. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118984475.
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Jacob-Lopes, Eduardo, Leila Queiroz Zepka, and Maria Isabel Queiroz, eds. Energy from Microalgae. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-69093-3.
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Cooper, Vivienne Cassie. Microalgae: Microscopic marvels. Hamilton, N.Z: Riverside Books, 1996.
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Jacob-Lopes, Eduardo, Maria Isabel Queiroz, and Leila Queiroz Zepka, eds. Pigments from Microalgae Handbook. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-50971-2.
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Borowitzka, Michael A., John Beardall, and John A. Raven, eds. The Physiology of Microalgae. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-24945-2.
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Zafaralla, Macrina Tamayo. Microalgae of Taal Lake. Bicutan, Taguig, Metro Manila, Philippines: National Academy of Science and Technology, Dept. of Science and Technology, 1998.
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Moheimani, Navid R., Mark P. McHenry, Karne de Boer, and Parisa A. Bahri, eds. Biomass and Biofuels from Microalgae. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-16640-7.
Full textBook chapters on the topic "Microalgae"
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Tebbani, Sihem, Filipa Lopes, Rayen Filali, Didier Dumur, and Dominique Pareau. "Microalgae." In CO2Biofixation by Microalgae, 1–22. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118984475.ch1.
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Muthukumaran, M. "Microalgae." In Environmental Management Technologies, 201–14. New York: CRC Press, 2022. http://dx.doi.org/10.1201/9781003239956-12.
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Singh, Preeti, Rahul Kunwar Singh, and Dhananjay Kumar. "MICROALGAE." In Microbes for Climate Resilient Agriculture, 57–74. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2017. http://dx.doi.org/10.1002/9781119276050.ch4.
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Singh, Amit Kumar, and Abhay K. Pandey. "Microalgae." In Recent Advances in Environmental Management, 167–95. First edition. | Boca Raton, Florida : A CRC title, part of the Taylor & Francis imprint, a member of the Taylor & Francis Group, the academic division of T&F Informa plc, 2019.: CRC Press, 2018. http://dx.doi.org/10.1201/9781351011259-7.
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Pacheco, Diana, Ana Cristina Rocha, Tiago Verdelhos, and Leonel Pereira. "Microalgae." In Removal of Refractory Pollutants from Wastewater Treatment Plants, 531–48. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003204442-29.
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Vidya, D., K. Nayana, A. Srinivasa Rao, C. Periyasamy, K. Suresh Kumar, K. Arun Kumar, and P. V. Subba Rao. "Microalgae." In Algal Biotechnology, 277–91. Boca Raton: CRC Press, 2024. http://dx.doi.org/10.1201/9781003219194-22.
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Nag, Radhakanta, Bidhu Bhusan Makut, Pritikrishna Majhi, and Saubhagya Manjari Samantaray. "Microalgae." In Algal Biotechnology, 238–45. Boca Raton: CRC Press, 2024. http://dx.doi.org/10.1201/9781003219194-19.
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Kumar, Arun, and Jay Shankar Singh. "Integrated Microalgal Wastewater Remediation and Microalgae Cultivation." In Microalgae in Waste Water Remediation, 195–216. First edition. | Boca Raton : CRC Press, Taylor & Francis Group, 2021.: CRC Press, 2021. http://dx.doi.org/10.1201/9780429298080-11.
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Barteneva, Natasha S., Aigul Kussanova, Veronika Dashkova, Ayagoz Meirkhanova, and Ivan A. Vorobjev. "Using Virtual Filtering Approach to Discriminate Microalgae by Spectral Flow Cytometer." In Methods in Molecular Biology, 23–40. New York, NY: Springer US, 2023. http://dx.doi.org/10.1007/978-1-0716-3020-4_2.
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AbstractFluorescence methods are widely used for the study of marine and freshwater phytoplankton communities. However, the identification of different microalgae populations by the analysis of autofluorescence signals remains a challenge. Addressing the issue, we developed a novel approach using the flexibility of spectral flow cytometry analysis (SFC) and generating a matrix of virtual filters (VF) which allowed thorough examination of autofluorescence spectra. Using this matrix, different spectral emission regions of algae species were analyzed, and five major algal taxa were discriminated. These results were further applied for tracing particular microalgae taxa in the complex mixtures of laboratory and environmental algal populations. An integrated analysis of single algal events combined with unique spectral emission fingerprints and light scattering parameters of microalgae can be used to differentiate major microalgal taxa. We propose a protocol for the quantitative assessment of heterogenous phytoplankton communities at the single-cell level and monitoring of phytoplankton bloom detection using a virtual filtering approach on a spectral flow cytometer (SFC-VF).
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Liu, Jin, and Feng Chen. "Biology and Industrial Applications of Chlorella: Advances and Prospects." In Microalgae Biotechnology, 1–35. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/10_2014_286.
Full textConference papers on the topic "Microalgae"
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Kolesovs, Sergejs, and Pavels Semjonovs. "Mixotrophic and heterotrophic cultivation of different microalgae species on dairy by-products for further supplementation of poultry diet." In 81st International Scientific Conference of the University of Latvia. University of Latvia, 2023. http://dx.doi.org/10.22364/iarb.2023.03.
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Use of alternative cultivation substrates, for instance dairy industry by-products, can significantly reduce the production costs of microalgal biomass. However, dairy by-products are found to be problematic co-substrate for many microalgae, due to inability to hydrolyse lactose. The focus of this study was to assess the ability of microalgal strains to produce biomass in media supplemented with lactose, glucose and galactose. Among them only microalgae Chromochloris zofingiensis was capable to assimilate effectively all three sugars.
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Malcata, F. Xavier. "Engineering of microalgae toward biodiesel: Facts and prospects." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/jeul5047.
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Excessive release to the atmosphere of greenhouse-effect gases—arising from combustion of fossil fuels, has urged a worldwide search for alternative sources of environment-friendly fuels; microalgae constitute an interesting possibility, owing to their widespread presence in most habitats and unique ability to synthesize oil. Microalgae require indeed only sunlight and water to grow—both freely available; together with CO2 as source of carbon—which concomitantly conveys a path for its direct sequestering from the atmosphere; and low-cost inorganic sources of phosphorus and nitrogen. However, the efficiency of the associated metabolic processes is still poor—and this has so far hampered economic feasibility of such microbial factories for eventual manufacture of biodiesel. Recent advances in genetic engineering tools, systems and synthetic biology, and bioinformatics and omics have widened the portfolio of possibilities for tailor-made genome engineering of microalgae. A holistic approach is needed to metabolic engineering, in which various aspects of cellular metabolism—including transcription factors, transporters, competing pathways, and balance between growth and proliferation are to be taken into account. In attempts to harness the potential of genetic engineering upon microalga-mediated oil production, a realistic assessment of risks and opportunities is a must. The current state-of-the-art of metabolic engineering approaches will accordingly be presented, aimed at enhancing lipid productivity by microalgal strains; technical issues will be critically discussed as well. An overview of the challenges and prospects for technical applicability of such techniques will be tackled, focused on oil for esterification downstream as biodiesel—along with ethical concerns associated to large-scale utilization of such tools.
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Ma, Jian, and Oliver Hemmers. "Thermo-Economic Analysis of Microalgae Co-Firing Process for Fossil Fuel-Fired Power Plants." In ASME 2010 4th International Conference on Energy Sustainability. ASMEDC, 2010. http://dx.doi.org/10.1115/es2010-90186.
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A thermoeconomic analysis of microalgae co-firing process for fossil fuel-fired power plants is studied. A process with closed photobioreactor and artificial illumination is evaluated for microalgae cultivation, due to its simplicity with less influence from climate variations. The results from this process would contribute to further estimation of process performance and investment. The concept of co-firing (coal-microalgae or natural gas-microalgae) includes the utilization of CO2 from power plant for microalgal biomass culture and oxy-combustion of using oxygen generated by biomass to enhance the combustion efficiency. As it reduces CO2 emission by recycling it and uses less fossil fuel, there are concomitant benefits of reduced GHG emissions. The by-products (oxygen) of microalgal biomass can be mixed with air or recycled flue gas prior to combustion, which will have the benefits of lower nitrogen oxide concentration in flue gas, higher efficiency of combustion, and not too high temperature (avoided by available construction materials) resulting from coal combustion in pure oxygen. Two case studies show that there are average savings about $0.386 million/MW/yr and $0.323 million/MW/yr for coal-fired and natural gas-fired power plants, respectively. These costs saving are economically attractive and demonstrate the promise of microalgae technology for reducing greenhouse gas (GHG) emission.
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Mienis, Esther, and Imogen Foubert. "Effect of ultrasound disruption on lipid extraction from Nannochloropsis sp." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/kvad7452.
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Photoautotrophic microalgae are a novel source of biomass rich in lipids containing nutritionally interesting n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). However, microalgae incorporated into foods as whole biomass may lead to limited n-3 LC-PUFA uptake by the human body. Incorporation of microalgal oil instead of whole biomass is an interesting alternative. The extraction efficiency of these lipids can be enhanced by adding a cell disruption step during lipid extraction. Ultrasound assisted extraction (UAE) to enhance lipid recovery from microalgae has been covered in recent literature. UAE is used to speed up lipid extraction for analytical purposes or for industrially applicable lipid extraction of microalgae. In addition, the ultrasonication and lipid extraction by organic solvents of microalgal biomass has been performed in different set-ups: simultaneous ultrasonication and lipid extraction or ultrasonication and subsequent lipid extraction, ultrasonication of wet biomass or dry biomass. Often, no reference method is included to which the lipid extraction efficiency using UAE is compared and the total lipid content of the biomass is not always specified making it impossible to calculate the extraction efficiency. Therefore, the effectiveness of this cell disruption technique for industrial microalgae processing has not consistently been proven in literature. This study investigates the effect of UAE of Nannochloropsis sp. biomass on the lipid extraction efficiency and the lipid quality, expressed as free fatty acid content and peroxide value. The effect of UAE on wet and dry biomass in the absence or presence of organic solvents is compared. The effect of the solvent system, ultrasonication power and ultrasonication time is studied.The results show that the lipid extraction efficiency increases after UAE. The presence of some solvent systems leads to higher lipid extraction efficiency when UAE is performed on dry biomass compared to wet biomass while for other solvent systems, this is reversed.
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Kolesovs, Sergejs, Kristaps Neiberts, and Pavels Semjonovs. "Use of microalgae Scenedesmus quadricauda and Chlorella vulgaris living-cells suspensions for plant biostimulation." In 81st International Scientific Conference of the University of Latvia. University of Latvia, 2023. http://dx.doi.org/10.22364/iarb.2023.04.
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Up to date research on microalgae as plant biostimulants remains fragmented and use of living microalgal cell suspensions is understudied. This research focuses on use of Scenedesmus quadricauda and Chlorella vulgaris living-cells suspensions as growth stimulants for garden cress (Lepidium sativum). Different concentrations of microalgal biomass suspensions were tested. It was found that plant treatment with S. quadricauda biomass 0.8 g/L (dry weight) suspension resulted in a significant improvement in L. sativum seeds germination and growth rate.
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Floume, Timmy, Thomas Coquil, and Julien Sylvestre. "Microalgae photonics." In SPIE Eco-Photonics, edited by Pierre Ambs, Dan Curticapean, Claus Emmelmann, Wolfgang Knapp, Zbigniew T. Kuznicki, and Patrick P. Meyrueis. SPIE, 2011. http://dx.doi.org/10.1117/12.883380.
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Kelechi, Faith Mmesomachukwu, and Chukwuebuka Samuel Nwafor. "Application of Hydrothermal Liquefaction Procedure for Microalgae-To-Biofuel Conversion." In SPE Nigeria Annual International Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/212014-ms.
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Abstract The thermal depolymerization process is also known as Hydrothermal liquefaction(HTL) Is used in converting macro/micro molecules, under temperatures of about 280°C and 370°C and pressures that are in the range from 10 to 25 MPa and into crude such as oil. The oil is composed of high energy density and low heating values of 33.8-36.9 MJ/Kg and 5-20 wt% renewables and oxygen. Presently microalgae are used industrially in producing high-quality products for food additives. Also, the microalgae are environmentally friendly, as it is used in the treatment of wastewater, control in the mitigation of industrial CO2 emission and atmospheric CO2 capturing. Due to environmental issues, microalgal are converted from biomass to biofuel. Recently HTL has drawn more attention, as it can be used in the refinery industry. This paper is also concerned with solving environmental issues using microalgae as an effective method for biomass to biofuel conversion. One significant advantage of HTL is the possibility of using fresh microalgae after harvesting, the processing of biomass and increased thermodynamic efficiency. The latter is achieved due to high HTL temperature and pressure which creates an avenue for more heat recovery.
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HANSEL, EZEQUIEL, Alice Costa Kiperstok, Rodrigo Gomes Guimaraes, and Emerson Andrade Sales. "CLAY AS A SUBSTRATUM MATERIAL FOR MICROALGAE BIOFILM CULTIVATION." In I South Florida Congress of Development. CONGRESS PROCEEDINGS I South Florida Congress of Development - 2021, 2021. http://dx.doi.org/10.47172/sfcdv2021-0025.
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The production of microalgae faces several obstacles. The bioreactors and processes used today in microalgae cultivation are expensive or lack optimization to scale up. Furthermore, harvesting, concentrating and dewatering, while using a cheap and suitable photobioreactor are the main problems that we need to be overcome to achieve viability in the process. The Clay Ceramic Bioreactor (CCBR) was built using only clay and wood sawdust and was designed to grow an immobilized microalgal biofilm while having almost complete separation from the liquid culture medium, reducing the consumption of water and energy. Results showed that the wood sawdust particle size should be sifted in a mesh size 10 and mixed in a proportion of 33% of sawdust and 67% of red clay and a maximum firing temperature of 900oC. Maximum dry biomass production of 3.71 g.m-2.d-1 was achieved within 7 days of cultivation, with no CO2 addition and a low light intensity of 45 µmol.m?2.s?1. The biomass was harvested through simple scraping. Initial results indicate a great potential for the use of clay as substratum and further tests should be carried out to scale up and optimize microalgae production,
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HANSEL, EZEQUIEL, Alice Costa Kiperstok, Rodrigo Gomes Guimaraes, and Emerson Andrade Sales. "CLAY AS A SUBSTRATUM MATERIAL FOR MICROALGAE BIOFILM CULTIVATION." In I South Florida Congress of Development. CONGRESS PROCEEDINGS I South Florida Congress of Development - 2021, 2021. http://dx.doi.org/10.47172/sfcdv2021-0063.
Full textAbstract:
The production of microalgae faces several obstacles. The bioreactors and processes used today in microalgae cultivation are expensive or lack optimization to scale up. Furthermore, harvesting, concentrating and dewatering, while using a cheap and suitable photobioreactor are the main problems that we need to be overcome to achieve viability in the process. The Clay Ceramic Bioreactor (CCBR) was built using only clay and wood sawdust and was designed to grow an immobilized microalgal biofilm while having almost complete separation from the liquid culture medium, reducing the consumption of water and energy. Results showed that the wood sawdust particle size should be sifted in a mesh size 10 and mixed in a proportion of 33% of sawdust and 67% of red clay and a maximum firing temperature of 900oC. Maximum dry biomass production of 3.71 g.m-2.d-1 was achieved within 7 days of cultivation, with no CO2 addition and a low light intensity of 45 µmol.m?2.s?1. The biomass was harvested through simple scraping. Initial results indicate a great potential for the use of clay as substratum and further tests should be carried out to scale up and optimize microalgae production,
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Nagarajan, R., Aatmesh Jain, and Kamalkishore Vora. "Biodiesel from Microalgae." In Symposium on International Automotive Technology 2017. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2017. http://dx.doi.org/10.4271/2017-26-0077.
Full textReports on the topic "Microalgae"
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Johnson, D. A., and S. Sprague. Liquid Fuels from Microalgae. Office of Scientific and Technical Information (OSTI), August 1987. http://dx.doi.org/10.2172/920198.
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Barclay, W., J. Johansen, P. Chelf, N. Nagle, P. Roessler, and P. Lemke. Microalgae culture collection, 1986-1987. Office of Scientific and Technical Information (OSTI), December 1986. http://dx.doi.org/10.2172/6953341.
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Agasteswar Vadlamani, Agasteswar Vadlamani. Discovering natural antibiotics from extremophile microalgae. Experiment, December 2016. http://dx.doi.org/10.18258/8772.
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Johansen, J. R., P. Lemke, N. J. Nagle, P. Chelf, P. G. Roessler, R. Galloway, and S. Toon. Addendum to Microalgae Culture Collection 1986-1987. Office of Scientific and Technical Information (OSTI), December 1987. http://dx.doi.org/10.2172/914655.
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Sayre, Richard. Optimization of Biofuel Production from Transgenic Microalgae. Fort Belvoir, VA: Defense Technical Information Center, May 2008. http://dx.doi.org/10.21236/ada586572.
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Cooksey, K. E. Collection and Screening of Microalgae for Lipid Production. Office of Scientific and Technical Information (OSTI), May 1987. http://dx.doi.org/10.2172/1068593.
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Brown, L. M. Biodiesel from Microalgae: Complementarity in a Fuel Development Strategy. Office of Scientific and Technical Information (OSTI), August 1993. http://dx.doi.org/10.2172/921199.
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Wheatcroft, Robert A. Feedbacks Between Bottom Roughness, Bioturbation Intensity and Epibenthic Microalgae. Fort Belvoir, VA: Defense Technical Information Center, September 1999. http://dx.doi.org/10.21236/ada613925.
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Weissman, J. C., D. M. Tillett, and R. P. Goebel. Design and operation of an outdoor microalgae test facility. Office of Scientific and Technical Information (OSTI), October 1989. http://dx.doi.org/10.2172/7024835.
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Maxwell, E. L., A. G. Folger, and S. E. Hogg. Resource evaluation and site selection for microalgae production systems. Office of Scientific and Technical Information (OSTI), May 1985. http://dx.doi.org/10.2172/5585709.
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