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| Registros recuperados: 10 | |
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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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| Gueguen, Marielle; Bardouil, Michele; Baron, Regis; Lassus, Patrick; Truquet, Philippe; Massardier, Julie; Amzil, Zouher. |
| Contamination of shellfish by paralytic shellfish poisoning ( PSP) toxins poses an economic threat to shellfish farmers. As contaminated shellfish cannot be harvested for long periods of time, it would be very useful to develop processes to optimise and shorten their detoxification. In this study, Pacific oysters Crassostrea gigas were first experimentally contaminated over a period of 13 days with a continuous flow of toxic Alexandrium minutum cultures at concentrations ranging from 150 to 200 cell ml(-1) ( toxin content after 13 days of contamination 438 mu g STX equiv. 100 g(-1) wet weight). Then, two different detoxification treatments were tested and showed detoxification rates greater than those observed in coastal environments. The first treatment... |
| Tipo: Text |
Palavras-chave: Alexandrium minutum; Crassostrea gigas; Detoxification; Inorganic matter; Organic matter; PSP; Paralytic shellfish poisoning. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3896.pdf |
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| Haberkorn, Hansy; Lambert, Christophe; Le Goic, Nelly; Moal, Jeanne; Suquet, Marc; Gueguen, Marielle; Sunila, Inke; Soudant, Philippe. |
| This study assessed the effects of an artificial bloom of the toxin-producing dinoflagellate, Alexandrium minutum, upon nutrition related processes and reproductive output of the Pacific oyster, Crassostrea gigas. Oysters were exposed to A. minutum, Paralytic Shellfish Toxins (PST) producer and compared to a control batch of oysters fed Isochrysis galbana clone Tahitian (T.Iso). The experiment was performed in June 2008, when oysters were found ripe. Several physiological variables of oysters, such as PSTs accumulation, digestive gland and histological observations as well as spermatozoa quality, were measured at the end of the exposure. Results indicate that the digestive gland was greatly impacted upon A. minutum exposure. Monoacylglycerol and... |
| Tipo: Text |
Palavras-chave: Harmful algae; Alexandrium minutum; Oyster; Nutrition-related processes; Reproductive output. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00008/11927/8653.pdf |
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| Haberkorn, Hansy; Lambert, Christophe; Le Goic, Nelly; Gueguen, Marielle; Moal, Jeanne; Palacios, Elena; Lassus, Patrick; Soudant, Philippe. |
| The effects of an artificial bloom of the toxin-producing dinoflagellate, Alexandrium minutum, upon physiological parameters of the Pacific oyster, Crassostrea gigas, were assessed. Diploid and triploid oysters were exposed to cultured A. minutum and compared to control diploid and triploid oysters fed T. Isochrysis. Experiments were repeated twice, in April and mid-May 2007, to investigate effects of maturation stage on oyster responses to A. minutum exposure. Oyster maturation stage, Paralytic Shellfish Toxin (PST) accumulation, as well as several digestive gland and hematological variables, were assessed at the ends of the exposures. In both experiments, triploid oysters accumulated more PSTs (approximately twice) than diploid oysters. Significant... |
| Tipo: Text |
Palavras-chave: Oysters; Ploidy; Physiology; Harmful-algal bloom; Alexandrium minutum; PST accumulation. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00003/11378/7988.pdf |
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| Gueguen, Marielle; Lassus, Patrick; Laabir, Mohamed; Bardouil, Michele; Baron, Regis; Sechet, Veronique; Truquet, Philippe; Amzil, Zouher; Barille, Laurent. |
| The occurrence of new phytoplankton species in a coastal area may be explained by the import of shellfish containing whole live algal cells in their digestive tracts. Indeed, shellfish containing toxic algal cells can induce both primary contaminations in safe areas ( initially free from toxic microalgae), and secondary contaminations of other shellfish growing in the same area via the faeces of the imported animals. To mitigate this problem, shellfish need to be placed in a separate holding tank and their intestinal content purged. For a deeper understanding of the risks associated with transferring contaminated shellfish, oysters ( Crassostrea gigas) and mussels ( Mytilus edulis) were purposely fed either Alexandrium minutum or A. catenella (... |
| Tipo: Text |
Palavras-chave: Risk assessment; Toxic phytoplankton; Uptake; Gut passage; Mytilus edulis; Crassostrea gigas. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3897.pdf |
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| Gueguen, Marielle; Baron, Regis; Bardouil, Michele; Haberkorn, Hansy; Soudant, Philippe; Truquet, Philippe; Lassus, Patrick. |
| The purpose of this study was to assess paralytic phycotoxin uptake in diploid and triploid oysters at two stages of their sexual cycle corresponding to their status in early summer (June) and winter (November). Samples of diploid and triploid oysters were exposed to a toxic culture of Alexandrium minutum for 4 days in each season. No significant differences in filtration or clearance rates were observed during either November or June experiments. When diploid oysters were at resting stage (November), toxin uptake showed no significant difference between the ploidy classes. In contrast, when the diploid oysters were at the peak of their sexual maturation (June), the triploid oysters were seen to accumulate almost double the amount of paralytic toxins as... |
| Tipo: Text |
Palavras-chave: Paralytic shellfish poisoning; Crassostrea gigas; Diploid; Triploid; Contamination. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00087/19796/17487.pdf |
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| Gueguen, Marielle; Baron, Regis; Bardouil, Michele; Truquet, Philippe; Haberkorn, Hansy; Lassus, Patrick; Barille, Laurent; Amzil, Zouher. |
| The aim of this study was to evaluate the importance of biotransformation of paralytic shellfish toxins during the detoxification process in contaminated oysters. Mathematical models based upon the detoxification patterns of digestive gland and other tissues were developed. It was demonstrated that biotransformations do not seem to play an important role in digestive gland or other tissue detoxification kinetics with our data set. Moreover, different toxin transfers from digestive gland toward other tissues were investigated. No significant transfer was highlighted in our data set. These first conclusions were drawn after comparing the results obtained from 13 biotransformations and identifiable transfer scenarios. Finally, to determine a more robust... |
| Tipo: Text |
Palavras-chave: Detoxification kinetics modelling; Biotransformation of saxitoxin analogues; Oyster. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00049/16047/14309.pdf |
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| Lassus, Patrick; Amzil, Zouher; Baron, Regis; Sechet, Veronique; Barille, Laurent; Abadie, Eric; Bardouil, Michele; Sibat, Manoella; Truquet, Philippe; Berard, Jean-baptiste; Gueguen, Marielle. |
| In October and November 2003 a bloom of the toxic dinoflagellate Alexandrium catenella was observed in the North-east zone of Thau lagoon (French Mediterranean coast). Sea water samples were collected every hours to evaluate time-related variations of phytoplankton concentrations and to compare the relative ratio of A. catenella versus other phytoplankton species during the outbreak. From these observations, trials using recirculated sea water systems were performed to: i) evaluate the physiological effects on oyster of increasing proportions of A. catenella within a mixed microalgal diet where the non-toxic diatom Thalassiosira weissflogii was present at concentration: 1500 cells ml(-1), ii) compare the effect of two temperatures (12 degrees C and 18... |
| Tipo: Text |
Palavras-chave: Mediterranean Sea; Alexandrium catenella; Toxin content; Model; Crassostrea gigas; Paralytic shellfish poisoning. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2624.pdf |
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| Gueguen, Marielle; Amiard, Jean-claude; Arnich, Nathalie; Badot, Pierre-marie; Claisse, Didier; Guerin, Thierry; Vernoux, Jean-paul. |
| Shellfish farming is a common industry along European coasts. According to the 2005–2006 data from the French National Shellfish Farming Committee (CNC – Comité National de la Conchyliculture 2010; see Table 1 for a list of acronyms and abbreviations used in this chapter), Spain is the largest shellfish producer in Europe (∼270,000 t) and France ranks second, producing 200,000 t of shellfish annually. France is the leading European oyster producer, with an annual output of 130,000 t of Crassostrea gigas, and ranks fourth in the world after China, Japan, and Korea. The top three European mussel (Mytilus edulis and Mytilus galloprovincialis) producers are Spain (260,000 t), Denmark (80,000 t), and France (65,000 t). For other shellfish, the French annual... |
| Tipo: Text |
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| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00039/14995/12622.pdf |
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| Registros recuperados: 10 | |
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