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Registros recuperados: 122 | |
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Long, Marc; Paul-pont, Ika; Hegaret, Helene; Moriceau, Brivaela; Lambert, Christophe; Huvet, Arnaud; Soudant, Philippe. |
To understand the fate and impacts of microplastics (MP) in the marine ecosystems, it is essential to investigate their interactions with phytoplankton as these may affect MP bioavailability to marine organisms as well as their fate in the water column. However, the behaviour of MP with marine phytoplanktonic cells remains little studied and thus unpredictable. The present study assessed the potential for phytoplankton cells to form hetero-aggregates with small micro-polystyrene (micro-PS) particles depending on microalgal species and physiological status. A prymnesiophycea, Tisochrysis lutea, a dinoflagellate, Heterocapsa triquetra, and a diatom, Chaetoceros neogracile, were exposed to micro-PS (2 μm diameter; 3.96 μg L−1) during their growth culture... |
Tipo: Text |
Palavras-chave: Polystyrene; Microplastic; Aggregates; Microalgae; Marine; Phytoplankton. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00389/50016/50735.pdf |
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Galès, Amandine; Bonnafous, Anaïs; Carré, Claire; Jauzein, Vincent; Lanouguère, Elodie; Le Floc'H, Emilie; Pinoit, Joanna; Poullain, Clothilde; Roques, Cécile; Sialve, Bruno; Simier, Monique; Steyer, Jean-philippe; Fouilland, Eric. |
Several studies focused on wastewater treatment in High Rate Algal Ponds (HRAP) suggest that highly variable climatic conditions cause large variations of microalgal biomass productivity. In the present study, we show that similar carbon, nitrogen and phosphorus removal efficiencies were reached in different HRAPs treating urban wastewaters located in two different temperate (Mediterranean and oceanic) climates. Furthermore, similar ecological successions were observed in these HRAPs. During the start-up phase, the consumption of organic matter by detritivores, already present in the wastewater, appears to be necessary for the microalgae to grow within two weeks in spring. The growth of the rapid-growing species, Chlorella sp., followed by the... |
Tipo: Text |
Palavras-chave: Microalgae; Predators; Bacteria; Urban effluents; Ammonia and phosphate removal. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00490/60210/63713.pdf |
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Pasquet, Virginie; Cherouvrier, Jean-rene; Farhat, Firas; Thiery, Valerie; Piot, Jean-marie; Berard, Jean-baptiste; Kaas, Raymond; Serive, Benoit; Patrice, Thierry; Cadoret, Jean-paul; Picot, Laurent. |
The performance of microwaves irradiation (MAE and VMAE) to extract pigments from two marine microalgae was compared to conventional processes (cold and hot soaking and ultrasound-assisted extraction). Pigments were quantified by RP-HPLC and extraction performance was assessed regarding rapidity, reproducibility and extraction yields. Scanning electron microscopy was used at all extraction steps to assess the impact of the process on microalgal cell integrity. Freeze-drying and pigments extraction preserved microalgae cell integrity (except sonication) and evoked agglutination in superposed cells layers. All processes performed on Dunaliella tertiolecta (chlorophyte) lead to rapid pigments extraction, and equivalent pigments extraction yields, the absence... |
Tipo: Text |
Palavras-chave: Pigments; Microalgae; Microwave; Extraction; Chlorophyll; Fucoxanthin; Carotene; MAE; VMAE. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00029/14059/11533.pdf |
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Dupraz, Valentin; Stachowski-haberkorn, Sabine; Wicquart, Jérémy; Tapie, Nathalie; Budzinski, Hélène; Akcha, Farida. |
Pesticides used in viticulture create a potential risk for the aquatic environment due to drift during application, runoff and soil leaching. The toxicity of sixteen pesticides and one metabolite were evaluated on the growth of two marine microalgae, Tisochrysis lutea and Skeletonema marinoi, in 96-h exposure assays conducted in microplates. For each substance, concentrations of stock solutions were analytically measured and abiotic assays were performed to evaluate the chemical stability of pesticides in microplates. For two chemicals, microalgae exposures were run simultaneously in microplates and culture flasks to compare EC50 calculated from the two exposure systems. Results from chemical analyses demonstrated the low stability of hydrophobic... |
Tipo: Text |
Palavras-chave: Microalgae; Microplates; Screening; Pesticides; Toxicity; Exposure characterisation. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00474/58558/61113.pdf |
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Martinez, Carlos; Mairet, Francis; Plaza, Luis; Sciandra, Antoine; Bernard, Olivier. |
The main resources limiting microalgae growth are typically phosphorus, nitrogen, and light. Based on the theory of the light limited chemostat, the variable cell quota approach, and photoacclimation models, we build a mathematical model for describing microalgae growth under limitation by these resources. The model is calibrated with a data set from the literature. Then, by numerical simulations, we find that under constant operation of the culture and constant environmental conditions (illumination, temperature, pH, etc.), solutions of the model approach towards either a positive or an extinction steady state. Based on the positive steady state, and in the context of wastewater treatment, we evaluate the capacity of microalgae to remove contaminants. We... |
Tipo: Text |
Palavras-chave: Control; Biotechnology; Wastewater treatment; Microalgae; Cell quota model. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00600/71188/69541.pdf |
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Mairet, Francis; Baron, Regis. |
The Droop model allows to represent microalgae growth limited by a nutrient, using a cell quota (also referred to as variable-yield) approach. Single-cell measurements have revealed quota heterogeneity in phytoplankton collected from field studies. Such heterogeneity can be due, among other factors, to spatial structure (e.g. in biogeochemical cycles in the ocean, or for photobioreactors connected in series). Nonetheless, quota heterogeneity is generally omitted in modelling studies, using an average quota approach, or included in size-structured or individual-based models. Here, we propose a distributed Droop equation to tackle this problem, considering subpopulation growth -in line with Droop macroscopic view- rather than cell division dynamics. We... |
Tipo: Text |
Palavras-chave: Population Balance Model; Variable-yield model; Cell Quota; Phytoplankton; Microalgae. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00600/71187/69542.pdf |
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Olofsson, Martin; Lamela, Teresa; Nilsson, Emmelie; Berge, Jean-pascal; Del Pino, Victoria; Uronen, Pauliina; Legrand, Catherine. |
Instead of sole nutrient starvation to boost algal lipid production, we addressed nutrient limitation at two different seasons (autumn and spring) during outdoor cultivation in flat panel photobioreactors. Lipid accumulation, biomass and lipid productivity and changes in fatty acid composition of Nannochloropsis oculata were investigated under nitrogen (N) limitation (nitrate:phosphate N:P 5, N:P 2.5 molar ratio). N. oculata was able to maintain a high biomass productivity under N-limitation compared to N-sufficiency (N:P 20) at both seasons, which in spring resulted in nearly double lipid productivity under N-limited conditions (0.21 g L−1 day−1) compared to N-sufficiency (0.11 g L−1 day−1). Saturated and monounsaturated fatty acids increased from 76% to... |
Tipo: Text |
Palavras-chave: Microalgae; Outdoor; Nannochloropsis; Large-scale; Lipids; Fatty acids; Nitrogen manipulation; Seasonal changes; Biofuels; High value products. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00184/29564/27902.pdf |
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Dupraz, Valentin; Coquille, Nathalie; Menard, Dominique; Sussarellu, Rossana; Haugarreau, Larissa; Stachowski-haberkorn, Sabine. |
A wild strain of Chaetoceros calcitrans and wild and diuron-resistant strains of Tetraselmis suecica, were exposed to the PSII inhibitor herbicides diuron and irgarol, individually and in mixtures. The effects of three concentrations of diuron and irgarol and four binary mixtures were evaluated on doubling time, relative reactive oxygen species and lipid content by flow cytometry, and on photosynthetic efficiency by pulse amplitude modulated fluorescence. In both wild strains, significant effects were observed for each molecule at the highest concentration tested: at irgarol 0.5 μg L−1, C. calcitrans was shown to be more sensitive than T. suecica (+52% and +19% in doubling time, respectively), whereas at diuron 5 μg L−1, T. suecica was more affected... |
Tipo: Text |
Palavras-chave: Microalgae; Herbicides; Antifouling; Irgarol; Diuron; Diuron resistance. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00319/43047/42658.pdf |
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Cellamare, M.; Duval, C.; Drelin, Y.; Djediat, C.; Touibi, N.; Agogue, H.; Leboulanger, C.; Ader, M.; Bernard, C. |
The saline-alkaline crater-lake Dziani Dzaha (Mayotte, Indian Ocean) is dominated by the bloom-forming cyanobacterium Arthrospira. However, the rest of the phototrophic community remains underexplored because of their minute dimension or lower biomass. To characterize the phototrophic microorganisms living in this ecosystem considered as a modern analog of Precambrian environments, several strains were isolated from the water column and stromatolites, and analyzed using the polyphasic approach. Based on morphological, ultrastructural and molecular (16S rRNA gene, 18S rRNA gene, 16S-23S ITS region, cpcBA-IGS locus) methods, seven filamentous cyanobacteria and the prasinophyte Picocystis salinarum were identified. Two new genera and four new cyanobacteria... |
Tipo: Text |
Palavras-chave: Cyanobacteria; Microalgae; Crater-lake; Saline-alkaline lake; Polyphasic approach; Arthrospira. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00443/55469/56991.pdf |
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Rumin, Judith; Nicolau, Elodie; Gonçalves De Oliveira Junior, Raimundo; Fuentes-grünewald, Claudio; Flynn, Kevin J; Picot, Laurent. |
A bibliographic database of scientific papers published by authors affiliated worldwide, especially focused in Europe and in the European Atlantic Area, and containing the keywords “microalga(e)” or “phytoplankton” was built. A corpus of 79,020 publications was obtained and analyzed using the Orbit Intellixir software to highlight the evolution of the research domain. Publication rates from 1960 to 2019, organization of the research, collaboration networks between countries and organizations, emerging and fading research concepts, major studied species, and associated concepts, as well as journals publishing microalgae research were considered. As a result, of the 79,020 papers published worldwide, 26,137 included authors from Europe (33% of world... |
Tipo: Text |
Palavras-chave: Biotechnology; European Atlantic Area; Microalgae; Phytoplankton; Research; Market; Bibliometrics. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00605/71725/70191.pdf |
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Réveillon, Damien; Tunin-ley, Alina; Grondin, Isabelle; Othmani, Ahlem; Zubia, Mayalen; Bunet, Robert; Turquet, Jean; Culioli, Gérald; Briand, Jean-françois. |
Marine microalgae and cyanobacteria have largely been studied for their biotechnological potential and proved their ability to produce a wide array of bioactive molecules. We investigated the antifouling potential of unexplored benthic tropical microalgae using anti-adhesion and toxicity bioassays against two major micro- and ma crobiofoulers, namely bacteria and barnacles. Fifty strains belonging to six phyla [Cyanobacteria, Miozoa (Dinoflagellata), Bacillariophyta, Cryptophyta, Rhodophyta and Haptophyta] were isolated from southwestern Islands of the Indian Ocean. They were chosen in order to represent as much as possible the huge biodiversity of such a rich tropical ecosystem. The associated chemodiversity was highlighted by both NMR- and LC-MS-based... |
Tipo: Text |
Palavras-chave: Microalgae; Antifouling; Bioassay; Chemodiversity; Bioprospecting; Metabolomics. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00454/56608/58333.pdf |
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Cognie, B; Barille, Laurent. |
Bivalves, by releasing inorganic nutrients, can stimulate the growth of the primary producers on which they feed. Dissolved excretion and mineralization of biodeposits (pseudofaeces and faeces), two indirect processes related to their feeding activity, have already been identified. This study investigated whether microalgal growth is also dependent on the mucus secreted by bivalves and rejected with their biodeposits. An experimental study based on algal growth tests was conducted to determine whether the mucus coating the pseudofaeces and faeces of the oyster Crassostrea gigas (Thunberg) could stimulate the growth of nine marine microalgae: a Prasinophyceae [Tetraselmis suecica (Butcher)] and eight Diatomophyceae [Amphora sp. (Ehrenberg), Chaetoceros sp.... |
Tipo: Text |
Palavras-chave: Bivalve; Microphyte; Mucus; Fèces; Pseudofèces; Bivalve; Microalgae; Mucus; Faeces; Pseudofaeces. |
Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43607/43926.pdf |
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Le Chevanton, Myriam. |
The use of algae-bacteria mixed culture has been suggested to improve performance of industrial microalgae culture. The present study aims to investigate impact of selected bacteria on Dunaliella sp. growth. 97 bacteria strains were isolated from a variety of marine microalgae cultures. The diversity of strains revealed members of α-and γ-proteobacteria, Cytophaga-Flavobacterium-Bacteroides and grampositive. A two-phase approach was then implemented to select bacteria that improve Dunaliella sp. growth, using an original high-throughput experimental device. Although a majority of bacteria induced performance reduction for Dunaliella sp., some resulted in significant improvements. In nitrogenlimited batch culture, the Alteromonas sp. bacteria demonstrated a... |
Tipo: Text |
Palavras-chave: Interactions; Microalgues; Bactéries; Dunaliella; Axénie; Interactions; Microalgae; Bacteria; Dunaliella; Axenic. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00187/29839/28291.pdf |
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Rumin, Judith; Bonnefond, Hubert; Saint-jean, Bruno; Rouxel, Catherine; Sciandra, Antoine; Bernard, Olivier; Cadoret, Jean-paul; Bougaran, Gael. |
Microalgae are currently emerging as one of the most promising alternative sources for the next generation of food, feed, cosmetics and renewable energy in the form of biofuel. Microalgae constitute a diverse group of microorganisms with advantages like fast and efficient growth. In addition, they do not compete for arable land and offer very high lipid yield potential. Major challenges for the development of this resource are to select lipid-rich strains using high-throughput staining for neutral lipid content in microalgae species. For this purpose, the fluorescent dyes most commonly used to quantify lipids are Nile red and BODIPY 505/515. Their fluorescent staining for lipids offers a rapid and inexpensive analysis tool to measure neutral lipid content,... |
Tipo: Text |
Palavras-chave: Nile red; BODIPY 505/515; Microalgae; Neutral lipid; Fluorescence; Biodiesel. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00257/36823/35451.pdf |
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Baudelet, Paul-hubert; Gagez, Anne-laure; Berard, Jean-baptiste; Juin, Camille; Bridiau, Nicolas; Kaas, Raymond; Thiery, Valerie; Cadoret, Jean-paul; Picot, Laurent. |
The glaucophyte Cyanophora paradoxa (Cp) was chemically investigated to identify pigments efficiently inhibiting malignant melanoma, mammary carcinoma and lung adenocarcinoma cells growth. Cp water and ethanol extracts significantly inhibited the growth of the three cancer cell lines in vitro, at 100 mu g.mL(-1). Flash chromatography of the Cp ethanol extract, devoid of c-phycocyanin and allophycocyanin, enabled the collection of eight fractions, four of which strongly inhibited cancer cells growth at 100 mu g.mL(-1). Particularly, two fractions inhibited more than 90% of the melanoma cells growth, one inducing apoptosis in the three cancer cells lines. The detailed analysis of Cp pigment composition resulted in the discrimination of 17 molecules, ten of... |
Tipo: Text |
Palavras-chave: Pigments; Microalgae; Cyanophora paradoxa; Melanoma; Cancer; Apoptosis; Zeaxanthin; Cryptoxanthin. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00177/28818/27289.pdf |
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Registros recuperados: 122 | |
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