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Registros recuperados: 40 | |
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Lepinay, Alexandra; Capiaux, Herve; Turpin, Vincent; Mondeguer, Florence; Lebeau, Thierry. |
Haslea ostrearia produces a water-soluble, blue-green pigment, called marennine, with proven economic benefits (as a bioactive compound used to green oysters, which improves their market value). Incomplete knowledge of the ecological features of this marine diatom complicates its cultivation. More specifically, the ecology of bacteria surrounding H. ostrearia in ponds is what remains unknown. The structure of this bacterial community was previously analyzed by means of PCR-TTGE before and after isolating H. ostrearia cells recovered from 4 localities in order to distinguish the relative parts of the biotope and biocenose and to describe the temporal dynamics of the bacterial community structure at two time scales (2 weeks vs. 9 months). The bacterial... |
Tipo: Text |
Palavras-chave: Biofilm; Ecology; Metabolic fingerprinting; Microalgae; Phycosphere; TTGE. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00326/43737/43344.pdf |
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Lepinay, Alexandra; Capiaux, Hervé; Turpin, Vincent; Mondeguer, Florence; Baron, Regis; Lebeau, Thierry. |
The marine diatom Haslea ostrearia produces a water-soluble blue-pigment named marennine of economic interest (e.g. in aquaculture for the greening of oysters). Up to date the studies devoted to ecological conditions under which this microalga develops never took into account the bacterial-H. ostrearia relationships. In this study the bacterial community was analysed by PCR-TTGE before and after H. ostrearia isolation cells recovered from 4 localities, to distinguish the relative part of the biotope and the biocenose and eventually to describe the temporal dynamic of the structure of the bacterial community. The bacterial structure of the phycosphere differed strongly from that of the bulk sediment. The similarity between bacteria recovered from the... |
Tipo: Text |
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Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00342/45365/44861.pdf |
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Briand, Enora; Reubrecht, Sébastien; Mondeguer, Florence; Sibat, Manoella; Hess, Philipp; Amzil, Zouher; Bormans, Myriam. |
Freshwater cyanobacteria are known for their ability to produce bioactive compounds, some of which have been described as allelochemicals. Using a combined approach of co‐cultures and analyses of metabolic profiles, we investigated chemically mediated interactions between two cyanobacterial strains, Microcystis aeruginosa PCC7806 and Planktothrix agardhii PCC7805. More precisely, we evaluated changes in growth, morphology and metabolite production and release by both interacting species. Co‐culture of Microcystis with Planktothrix resulted in a reduction of the growth of Planktothrix together with a decrease of its trichome size and alterations in the morphology of its cells. The production of intracellular compounds by Planktothrix showed a slight... |
Tipo: Text |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00470/58152/60632.pdf |
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Briand, Enora; Reubrech, Sébastien; Mondeguer, Florence; Sibat, Manoella; Hess, Philipp; Amzil, Zouher; Bormans, Myriam. |
Freshwater cyanobacteria are well known for their ability to produce a wide variety of bioactive compounds, some of which have been described as allelochemicals. There is growing evidence that these secondary metabolites play an important role in shaping community composition through biotic interactions; however, for the most part, their biological role and mode of regulation of the production are poorly understood. In temperate eutrophic freshwaters, Microcystis and Planktothrix often co-occur, with Planktothrix being an early colonizer and Microcystis appearing subsequently. We tested if the production of a range of peptides by co-existing species could be regulated through interspecific interactions. Using a combined approach of co-cultures and analyses... |
Tipo: Text |
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Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00374/48515/48794.pdf |
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Hess, Philipp; Geiger, Marie; Brochard, Solène; Lepretre, Thomas; Fessard, Valerie; Antignac, Jean-philippe; Dupont, Jacques; Sechet, Veronique; Vanel, Faustine; Mondeguer, Florence; Herve, Fabienne; Leborgne, Sabrina; Deslanglois, Gwenaëlle; Marshall, Lindsey; Rounds, Lucy; Guitton, Yann; Amzil, Zouher; Grovel, Olivier; Ruiz, Nicolas; Pouchus, Francois. |
Cette étude s’est inscrite dans un contexte d’évaluation de la salubrité des mollusques bivalves destinés à la consommation humaine. Ces organismes peuvent en effet accumuler des toxines, en particulier de microalgues, en concentrations importantes, pouvant induire des intoxications chez les personnes les consommant. Afin d’assurer la protection des consommateurs, les toxines réglementées sont recherchées dans les coquillages par techniques physico-chimiques. En parallèle, les toxines émergentes, potentiellement produites par d’autres organismes que les micro-algues telles que les micromycètes, peuvent être detectées par l’utilisation du test de toxicité aigüe sur souris. Cependant, ce bio-essai présente de très nombreux inconvénients, notamment éthiques... |
Tipo: Text |
Palavras-chave: Cytotoxicité; Toxicité sur larves de diptères; Activité antibactérienne; Bactéries marines; Toxines lipophiles; Micro-algues; Dinoflagellés; Micromycètes; Penicillium; Acide okadaïque; Azaspiracide; Pinnatoxine G; Vulcanodinium rugosum; Prorocentrum lima; Azadinium spinosum; Beauveria brongniartii. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00253/36470/35015.pdf |
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Haure, Joel; Hussenot, Jerome; Buzin, Florence; Dupuy, Beatrice; Palvadeau, Hubert; Penisson, Christian; Papin, Mathias; Nourry, Max; Lassus, Patrick; Marcaillou-le Baut, Claire; Mondeguer, Florence; Royer, F.; Amzil, Zouher; Belin, Catherine; Cardinal, Mireille; Le Grel, L.; Le Bihan, V.; Jaouen, P.; Massé, A.; Castaing, Jean-baptiste; Sabiri, Ne.; Pontié, M.. |
La contamination des denrées d’origine marine par des toxines algales (phycotoxines) a pris depuis quelques années une importance considérable. Ce phénomène est largement lié à l’augmentation du nombre de zones géographiques touchées ainsi qu’à la diversification des espèces toxinogènes et à l’identification de nouveaux composés toxiques. Les données épidémiologiques sont cependant encore peu nombreuses car elles sont liées à la mise en place de contrôles systématiques récents. L’Union Européenne a établi un Laboratoire Communautaire de référence pour les phycotoxines, situé à Vigo (Espagne) qui coordonne les activités des laboratoires Nationaux de références correspondants (en France c’est le LNR Phycotoxines de l’AFSSA qui assure cette mission). C’est... |
Tipo: Text |
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Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00092/20277/17922.pdf |
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Pardo, Sophie; Hess, Philipp; Simon, Elodie; Barille, Laurent; Geslin, Emmanuelle; Cognie, Bruno; Martin-jezequel, Véronique; Sechet, Véronique; Herrenknecht, Christine; Baron, Regis; Bourseau, Patrick; Amzil, Zouher; Masse, Anthony; Vandanjon, Laurent; Dumay, Justine; Lebeau, Thierry; Turpin, Vincent; Mondeguer, Florence; Petitgas, Pierre; Trouillet, Brice; Mercier, Denis; Guillotreau, Patrice; Guineberteau, Thierry; Mahevas, Stephanie; Schoefs, Franck; Sophie Pardo; Philipp Hess; Pauline Borgniet; Laurent Barillé; Emmanuelle Geslin; Bruno Cognie; Véronique Martin-Jezequel; Véronique Sechet; Christine Herrenknecht; Régis Baron; Patrick Bourseau; Zouher Amzil; Anthony Massé; Laurent Vandanjon; Justine Dumay; Thierry Lebeau; Vincent Turpin; Florence Mondeguer; Pierre Petitgas; Brice Trouillet. |
COSELMAR, a 4-year project financed by the Région des Pays de la Loire at 2.1 M€, officially started on the 7th January 2013. The project is coordinated by Philipp Hess (IFREMER) and Sophie Pardo (Université de Nantes-LEMNA) and falls under the Federation for Research Institut Universitaire Mer et Littoral (IUML, FR CNRS 3473)*. COSELMAR has also been approved by the Scientific Council of the MSH Ange Guépin. COSELMAR is a research project uniting 5 research units of IFREMER and 11 laboratories of the Université de Nantes, along with academic partners, and national and international industries. The aim is to achieve a better understanding of the marine and coastal ecosystems and the associated resources. The project will also provide insights into risk... |
Tipo: Text |
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Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00406/51793/52550.pdf |
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Geiger, Marie; Desanglois, Gwenaelle; Hogeveen, Kevin; Fessard, Valerie; Lepretre, Thomas; Mondeguer, Florence; Guitton, Yann; Herve, Fabienne; Sechet, Veronique; Grovel, Olivier; Pouchus, Yves-francois; Hess, Philipp. |
Pinnatoxin G (PnTX-G) is a marine toxin belonging to the class of cyclic imines and produced by the dinoflagellate Vulcanodinium rugosum. In spite of its strong toxicity to mice, leading to the classification of pinnatoxins into the class of “fast-acting toxins”, its hazard for human health has never been demonstrated. In this study, crude extracts of V. rugosum exhibited significant cytotoxicity against Neuro2A and KB cells. IC50 values of 0.38 µg mL−1 and 0.19 µg mL−1 were estimated on Neuro2A cells after only 24 h of incubation and on KB cells after 72 h of incubation, respectively. In the case of Caco-2 cells 48 h after exposure, the crude extract of V. rugosum induced cell cycle arrest accompanied by a dramatic increase in double strand DNA breaks,... |
Tipo: Text |
Palavras-chave: Dereplication; Cyclic imine; HRMS; Bioactivity; Pinnatoxins. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00156/26723/24802.pdf |
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Poirier, Laurence; Amiard, Jean-claude; Mondeguer, Florence; Quiniou, Francoise; Ruiz, Nicolas; Pouchus, Yves Francois; Montagu, Monique. |
Extraction followed by reverse phase liquid chromatography (LC)/electrospray ionization-ion trap-mass spectrometry (ESI-IT-MS) analysis has been successfully developed for the determination of peptaibols, fungal toxic metabolites, in marine sediments. Spiking experiments showed that the mean recovery of target compounds exceeded 85% at a spiking level of 10 ng/g of sediment (wet weight). Detection and quantification limits were 250 and 830 pg/g of sediment, respectively. The method developed constituted the first sensitive assay for quantification of peptaibol trace amounts in a natural environment. A concentration of 5 ng/g in sediment samples collected from Fier d'Ars was found. |
Tipo: Text |
Palavras-chave: Matched calibration; Matrix; Electrospray ionization ion trap mass spectrometry ESI IT MS; Marine fungal contamination; Trichoderma sp.; Fungal peptide metabolites. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2990.pdf |
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Poyer, Salome; Loutelier-bourhis, Corinne; Tognetti, Vincent; Joubert, Laurent; Enche, Julien; Bossee, Anne; Mondeguer, Florence; Hess, Philipp; Afonso, Carlos. |
Gonyautoxins are potent natural neurotoxic analogues of saxitoxin. Due to their biological activity and submilligram lethal dose for man, fast and efficient methods are required for their characterization. Recent advances in ion mobility-mass spectrometry (IM-MS) showed that differentiation of isomers could be achieved using specific experimental conditions involving particular buffer gases as well as cationic species. In this work, IM-MS experiments were carried out using alkali metal ions (Met = Li+, Na+ or K+) and different buffer gases (N2, N2O and CO2) to improve the differentiation of gonyautoxin isomers. The separation of [GTX + Met]+ ion was achieved for GTX2/3 and GTX1/4 from their Na or K adducts. For dcGTX2/3, the ion mobility separation can... |
Tipo: Text |
Palavras-chave: Ion mobility; Gonyautoxin; Collision cross-section; Alkali adduct. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00317/42863/42291.pdf |
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Marcaillou-le Baut, Claire; Haure, Joel; Mondeguer, Florence; Courcoux, Anne; Dupuy, Beatrice; Penisson, Christian. |
The objective of this study was to identify a possible effect of food on the acceleration of decontamination in blue mussels, Mytilus edulis, containing diarrhetic toxins belonging to the okadaic acid (OA) structural group. An experimental protocol was designed to describe and compare the decontamination kinetics and detoxification rates of naturally OA-contaminated mussels that had either received or not received food for three weeks. The protocol was applied in two trials (in June 2006 and June 2007, called Ker06 and Ker07), conducted one year apart on samples of mussels collected in the same area, at the same season. Okadaic acid (OA), the main lipophilic toxin produced by the toxic alga Dinophysis acuminata, was analysed over the course of the... |
Tipo: Text |
Palavras-chave: Mussel; Feeding; Digestive gland; Depuration; Okadaic acid; Acyl esters; Marine lipophilic biotoxins; Mass spectrometry. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00025/13650/10883.pdf |
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Mondeguer, Florence; Marcaillou-le Baut, Claire. |
Le littoral français est touché tous les ans par des proliférations d'algues toxiques dont l'ampleur géographique et la durée sont très variables selon les genres/espèces et les années. Par exemple, à partir du mois de mai, voire fin avril certaines années, les côtes sud de la Bretagne et celles des Pays de la Loire sont touchées par des proliférations de Dinophysis spp, genre responsable des intoxications diarrhéiques et cause la plus fréquente des fermetures de zones conchylicoles. Depuis 1988, la côte nord de la Bretagne est exposée à des efflorescences à Alexandrium minutum, producteur de toxines paralysantes. Ces fermetures répétées s'accompagnent d'une diminution, voire d'une cessation d'activité pour les établissements d'expédition car... |
Tipo: Text |
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Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/00154/26512/24630.pdf |
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Zendong, Zita; Herrenknecht, Christine; Abadie, Eric; Brissard, Charline; Tixier, Celine; Mondeguer, Florence; Sechet, Veronique; Amzil, Zouher; Hess, Philipp. |
Marine biotoxins are algal metabolites that can accumulate in fish or shellfish and render these foodstuffs unfit for human consumption. These toxins, released into seawater during algal occurrences, can be monitored through passive sampling. Acetone, methanol and isopropanol were evaluated for their efficiency in extracting toxins from algal biomass. Isopropanol was chosen for further experiments thanks to a slightly higher recovery and no artifact formation. Comparison of Oasis HLB, Strata-X, BondElut C18 and HP-20 sorbent materials in SPE-mode led to the choice of Oasis HLB, HP-20 and Strata-X. These three sorbents were separately exposed as passive samplers for 24 h to seawater spiked with algal extracts containing known amounts of okadaic acid (OA),... |
Tipo: Text |
Palavras-chave: Passive sampling; Oasis HLB; Strata-X; LOPE; PDMS; SPATT. |
Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00186/29756/28187.pdf |
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Fux, E; Marcaillou-le Baut, Claire; Mondeguer, Florence; Bire, R; Hess, Philipp. |
It has been demonstrated that polymeric resins can be used as receiving phase in passive samplers designed for the detection of lipophilic marine toxins at sea and was referred to as solid phase adsorption toxin tracking (SPATT). The present study describes the uptake and desorption behaviour of the lipophilic marine toxins okadaic acid (OA) and dinophysistoxin-1 (DTX1) from Prorocentrum lima cultures by five styrene-divinylbenzene based polymeric resins Sepabeads (R) SP850, Sepabeads (R) SP825L, Amberlite (R) XAD4, Dowex (R) Optipore (R) L-493 and Diaion (R) HP-20. All resins accumulated OA and DTX1 from the P. lima culture with differences in adsorption rate and equilibrium rate. Following statistical evaluation, HP-20, SP850 and SP825L demonstrated... |
Tipo: Text |
Palavras-chave: Polymeric resin; Dinophysistoxin 1; Okadaic acid; SPATT; Prorocentrum lima. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4739.pdf |
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Lepinay, Alexandra; Turpin, Vincent; Mondeguer, Florence; Grandet-marchant, Quentin; Capiaux, Herve; Baron, Regis; Lebeau, Thierry. |
A first insight on the interactions between bacteria isolated from monospecific cultures of the marine diatom Haslea ostrearia and this microalgae is described in this work. From 28 bacterial isolates, the maximal growth rate and the maximal cell concentration were on average 58% and 27% higher (max. 67% for isolate B22). Isolates B5, B10 (both Saccharospirillum sp.) and B22 (Rhodobacter sp.) were the most efficient. The geographical origin of H. ostrearia from which bacteria were isolated had no impact on the algal growth performances, and a given bacterial isolate led to the same algal growth irrespective of the geographical origin of H. ostrearia. To explain the results obtained, a comprehensive integrative strategy was conducted that analyzed the... |
Tipo: Text |
Palavras-chave: Bacterial selection; Plant-growth-promoting bacteria; Phycosphere; Metabolomics. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00429/54036/55340.pdf |
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Mondeguer, Florence; Souard, Florence; Guitton, Yann; Latimier, Marie; Quere, Julien; Sibat, Manoella; Hess, Philipp; Siano, Raffaele. |
Aquatic ecosystems worldwide have been negatively affected by eutrophication, many of them driven by increasing nutrient inputs from untreated domestic sewage and industrial and agricultural wastewater. During their life cycle, Alexandrium minutum and Scrippsiella donghaienis can produce resistant and revivable cysts that can accumulate in the sediments of the coastal marine environment for hundreds of years. As a working hypothesis, we presumed that these two genera have preserved their adaptation to such ecosystem changes in the form of cysts in the old sediments. From revivified cysts, some cultures of toxic and non-toxic dinoflagellates (A. minutum and S. donghaienis) were analyzed by a untargeted metabolomics approach by LC-HRMS to study the possible... |
Tipo: Text |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00440/55199/56664.pdf |
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Mondeguer, Florence; Lepinay, Alexandra; Capiaux, Hervé; Turpin, Vincent; Baron, Regis; Hess, Philipp; Lebeau, Thierry; Boug,. |
The marine diatom Haslea ostrearia [1] produces a water-soluble blue-pigment named marennine [2] of economic interest. But the lack of knowledge of the ecological conditions, under which this microalga develops in its natural ecosystem, more especially bacteria H. ostrearia interactions, prevents any optimization of its culture in well-controlled conditions. The structure of the bacterial community was analyzed by PCR-TTGE before and after the isolation of H. ostrearia cells recovered from 4 localities, to distinguish the relative part of the biotope and the biocenose and eventually to describe the temporal dynamic of the structure of the bacterial community at two time-scales. The differences in genetic fingerprints, more especially high between two H.... |
Tipo: Text |
Palavras-chave: Haslea ostrearia; Marine diatom; Co-culture microalgae; Bacterial community; PCR-TTGE; High Resolution Mass Spectrometry; Untargeted metabolomics. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00342/45367/44862.pdf |
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Registros recuperados: 40 | |
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