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Registros recuperados: 83 | |
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Rolland, Jean-luc; Medhioub, Walid; Vergnes, Agnes; Abi-khalil, Celina; Savar, Veronique; Abadie, Eric; Masseret, Estelle; Amzil, Zouher; Laabir, Mohamed. |
To better understand the effect of Paralytic Shellfish Toxins (PSTs) accumulation in the digestive gland of the Pacific oyster, Crassostrea gigas, we experimentally exposed individual oysters for 48 h to a PSTs producer, the dinoflagellate Alexandrium catenella. In comparison to the effect of the non-toxic Alexandrium tamarense, on the eight apoptotic related genes tested, Bax and BI.1 were significantly upregulated in oysters exposed 48 h to A. catenella. Among the five detoxification related genes tested, the expression of cytochrome P450 (CYP1A) was shown to be correlated with toxin concentration in the digestive gland of oysters exposed to the toxic dinoflagellate. Beside this, we observed a significant increase in ROS production, a decrease in... |
Tipo: Text |
Palavras-chave: Shellfish; Toxin; Biomarker; Expression; Phytoplankton. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00225/33606/32003.pdf |
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Ayache, Nour; Hervé, Fabienne; Lundholm, Nina; Amzil, Zouher; Caruana, Amandine. |
oxic Pseudo‐nitzschia australis strains isolated from French coastal waters were studied to investigate their capacity to adapt to different salinities. Their acclimation to different salinity conditions (10, 20, 30, 35 and 40) was studied on growth, photosynthetic capacity, cell biovolume and domoic acid (DA) content. The strains showed ability to acclimate to a salinity range from 20 to 40, with optimal growth rates between salinities 30 and 40. The highest cell biovolume was observed at the lowest salinity 20 and was associated with the lowest growth rate. Salinity did not affect the photosynthetic activity; Fv/Fm values and the pigment contents remained high with no significant difference among salinities. An enhanced production of zeaxanthin was,... |
Tipo: Text |
Palavras-chave: Acclimation; Climate change; Domoic acid; Pseudo-nitzschia australis; Physiology; Salinity. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00585/69684/67552.pdf |
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Medhioub, Walid; Sechet, Veronique; Truquet, Philippe; Bardouil, Michele; Amzil, Zouher; Lassus, Patrick; Soudant, Philippe. |
Growth and spirolide production of the toxic dinoflagellate Alexandrium ostenfeldii (Danish strain CCMP1773) were studied in batch culture and a photobioreactor (continuous cultures). First, batch cultures were grown in 450 mL flasks without aeration and under varying conditions of temperature (16 and 22 degrees C) and culture medium (L1, f/2 and L1 with addition of soil extract). Second, cultures were grown at 16 degrees C in 8 L aerated flat-bottomed vessels using L1 with soil extract as culture medium. Finally, continuous cultures in a photobioreactor were conducted at 18 degrees C in L1 with soil extract; pH was maintained at 8.5 and continuous stirring was applied. This study showed that A. ostenfeldii growth was significantly affected by temperature.... |
Tipo: Text |
Palavras-chave: Alexandrium ostenfeldii; Batch; Growth; Photobioreactor; Spirolide production. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00049/16050/15784.pdf |
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Derrien, Amelie; Terre Terrillon, Aouregan; Duval, Audrey; Lebrun, Luc; Doner, Anne; Rovillon, Georges-augustin; Amzil, Zouher; Le Bec, Claude. |
En cas de fermeture de zone de production pour cause de présence d'une espèce de micro algues toxique, une mesure prévoit pour les professionnels de la conchyliculture l'interdiction générale d'utilisation de l'eau de mer déjà pompée dans un bassin insubmersible. C'est dans ce contexte que la DGAL a sollicité l'appui du LER BO pour la mise en place d'une étude dans des conditions professionnelles. Cette étude vise à déterminer d'il existe un risque de contamination lors de l'immersion de coquillages non contaminés dans un bassun insubmersible rempli en eau de mer pompée dans une zone fermée pour cause de présence de micro-algues toxiques. Entre fin juin et début juillet, la présence de Dinophysis sp a entraîné la fermeture de la baie de Concarneau. Des... |
Tipo: Text |
Palavras-chave: Dinophysis; Toxines lipophiles; Acide okadaïque; Yessotoxines; Bassin insubmersible; Huîtres; Moules. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00486/59736/62831.pdf |
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Reveillon, Damien; Abadie, Eric; Sechet, Veronique; Brient, Luc; Savar, Veronique; Bardouil, Michele; Hess, Philipp; Amzil, Zouher. |
beta-N-methylamino-L-alanine (BMAA) is a neurotoxic non-protein amino acid suggested to be involved in neurodegenerative diseases. It was reported to be produced by cyanobacteria, but also found in edible aquatic organisms, thus raising concern of a widespread human exposure. However, the chemical analysis of BMAA and its isomers are controversial, mainly due to the lack of selectivity of the analytical methods. Using factorial design, we have optimized the chromatographic separation of underivatized analogues by a hydrophilic interaction chromatography coupled to tandem mass spectrometry (HILIC-MS/MS) method. A combination of an effective solid phase extraction (SPE) clean-up, appropriate chromatographic resolution and the use of specific mass spectral... |
Tipo: Text |
Palavras-chave: Cyanotoxins; BMAA; DAB; AEG; HILIC-MS/MS; Cyanobacteria; Bivalve mollusks; French Mediterranean. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00245/35579/34112.pdf |
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Neaud-masson, Nadine; Amzil, Zouher. |
L’Ifremer est chargé d’apporter à l’État et aux autres personnes morales de droit public son concours pour l’exercice de leurs responsabilités notamment pour le contrôle de la qualité des produits de la mer et du milieu marin. La mise en œuvre d’un Réseau d'Observation et de Surveillance du Phytoplancton et des Phycotoxines (REPHY) depuis sa création en 1984, répond à cette mission et le concours apporté à l’Administration Centrale se concrétise en un soutien aux autorités publiques dont la Direction Générale de l’Alimentation (DGAL) du Ministère de l’Agriculture, de l’Agroalimentaire et de la Forêt (MAAF), pour ce qui concerne l’application de la réglementation relative au suivi de la salubrité des zones de production de coquillages. Un changement majeur... |
Tipo: Text |
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Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00341/45243/44678.pdf |
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Castrec, Justine; Soudant, P.; Payton, L.; Tran, D.; Miner, Philippe; Lambert, C.; Le Goic, N.; Huvet, Arnaud; Quillien, Virgile; Boullot, F.; Amzil, Zouher; Hegaret, Helene; Fabioux, C.. |
Blooms of the dinoflagellate Alexandrium spp., known as producers of paralytic shellfish toxins (PSTs), are regularly detected on the French coastline. PSTs accumulate into harvested shellfish species, such as the Pacific oyster Crassostrea gigas, and can cause strong disorders to consumers at high doses. The impacts of Alexandrium minutum on C. gigas have often been attributed to its production of PSTs without testing separately the effects of the bioactive extracellular compounds (BECs) with allelopathic, hemolytic, cytotoxic or ichthyotoxic properties, which can also be produced by these algae. The BECs, still uncharacterized, are excreted within the environment thereby impacting not only phytoplankton, zooplankton but also marine invertebrates and... |
Tipo: Text |
Palavras-chave: Harmful algal bloom (HAB); Crassostrea gigas; Paralytic shellfish toxins (PST); Bioactive extracellular compounds (BEC); Histology; Behavior. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00435/54637/56042.pdf |
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Brissard, Charline; Herve, Fabienne; Sibat, Manoella; Sechet, Veronique; Hess, Philipp; Amzil, Zouher; Herrenknecht, Christine. |
The presence of Ostreopsis cf. ovata on the Mediterranean coast represents a serious concern to human health due to production of toxins–putative palytoxin and ovatoxins (ovatoxin-a, -b, -c, -d, -e, -f and -g). However, purified ovatoxins are not widely available and their toxicities are still unknown. In the present study, we report on HR LC-MS/MS analysis of a French Ostreopsis cf. ovata strain (IFR-OST-0.3 V) collected at Villefranche-sur-Mer (France) during a bloom in 2011. Investigation of this strain of Ostreopsis cf. ovata cultivated in our laboratory by ultra-high performance liquid chromatography coupled to high resolution mass spectrometry (UHPLC-HRMS) confirmed the production of ovatoxins -a to–e and revealed the presence of a new ovatoxin... |
Tipo: Text |
Palavras-chave: Ostreopsis cf. ovata; Palytoxin; Ovatoxins; U-HPLC/HR-MSn; Chromatographic separation. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00252/36302/34831.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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Brissard, Charline; Herrenknecht, Christine; Sechet, Veronique; Herve, Fabienne; Pisapia, Francesco; Harcouet, Jocelyn; Lemee, Rodolphe; Chomerat, Nicolas; Hess, Philipp; Amzil, Zouher. |
Ostreopsis cf. ovata produces palytoxin analogues including ovatoxins (OVTXs) and a putative palytoxin (p-PLTX), which can accumulate in marine organisms and may possibly lead to food intoxication. However, purified ovatoxins are not widely available and their toxicities are still unknown. The aim of this study was to improve understanding of the ecophysiology of Ostreopsis cf. ovata and its toxin production as well as to optimize the purification process for ovatoxin. During Ostreopsis blooms in 2011 and 2012 in Villefranche-sur-Mer (France, NW Mediterranean Sea), microalgae epiphytic cells and marine organisms were collected and analyzed both by LC-MS/MS and hemolysis assay. Results obtained with these two methods were comparable, suggesting ovatoxins... |
Tipo: Text |
Palavras-chave: Ostreopsis cf. ovata; Palytoxin & ovatoxins; Culture; Seafood contamination; LC-MS/MS; Hemolysis assay; Mediterranean Sea. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00199/31025/29428.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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Darius, Ht; Viallon, J; Gatti, Cm; Chinain, M; Roué, M; Sibat, Manoella; Amzil, Zouher; Hess, Philipp; Vandersea, Mw; Litaker, Rw; Tester, Pa. |
Tipo: Text |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00450/56181/57729.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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Marcaillou-le Baut, Claire; Masselin, Pierre; Bohec, Madeleine; Truquet, Philippe; Amzil, Zouher; Pouchus, Francois; Le Boterff, Jean; Verbist, Jean-françois; Vernoux, Jean-paul; Marais, Chantal; Simon, Jean-françois; Nizard, Gabrielle; Mercier, Géraldine; Choumiloff, Roxelan; Baron, Bruno. |
Cette étude est le résultat d'un travail de trois équipes: elle porte sur la comparaison du test souris avec différents bioessais déjà pratiqués en routine dans les laboratoires participants. Ces bioessais sont : - un test sur micro crustacé dont la méthodologie est normalisée et qui est très utilisé en écotoxicologie aquatique ; - un test de cytotoxicité à court terme qui a été mis au point pour cette étude. |
Tipo: Text |
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Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/00139/25035/23144.pdf |
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Medhioub, Walid; Gueguen, Marielle; Lassus, Patrick; Bardouil, Michele; Truquet, Philippe; Sibat, Manoella; Nejib, Medhioub; Philippe, Soudant; Mejdeddine, Kraiem; Amzil, Zouher. |
In the Gulf of Gabes (Tunisia, Eastern Mediterranean sea), the grooved carpet shell Ruditapes decussatus has been seen to contain persistent levels of gymnodimine (GYM) for several years. The present experimental work represents the first attempt to assess detoxification kinetics of fast-acting toxins (FAT) in marine molluscs fed specific diets of non-toxic algae (Isochrysis galbana). To find an optimal detoxification method, two experiments were performed in which clams were first fed the toxic dinoflagellate Karenia selliformis to artificially contaminate them with GYM, thus simulating the effect of natural toxic episodes. As a second step, the same clams were fed a non-toxic algae, I. galbana. to speed up the detoxification process. Changes in toxin... |
Tipo: Text |
Palavras-chave: Ruditapes decussates; Grooved carpet shell; Karenia selliformis; Gymnodimine; Toxicity; Detoxification. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/2010/publication-7488.pdf |
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Registros recuperados: 83 | |
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