Philippe Truquet

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Pacific oysters and king scallops placed individually in a recirculating flume were fed for 2 weeks with a constant concentration (120 cell ml) of a toxic strain of Alexandrium minutum. Fluorescence at the outlet of each experimental unit was measured continuously, and biodeposits were recovered twice daily to evaluate feeding time activity (FTA) and rates(More)
Azadinium spinosum (Elbrächter and Tillmann), a small marine dinoflagellate, has been recently described as a de novo producer of azaspiracid-1 and -2 (AZA1 and -2) diarrhoeic toxins. A culture of A. spinosum was established in our laboratory and optimised for pilot-scale production of this organism, to evaluate and understand AZA1 and -2 accumulation and(More)
Several experiments using a self-regulated system were conducted to define the factors likely to influence the uptake of paralytic shellfish poison (PSP) by oysters in the Penzé estuary (France, Brittany). Each 4-day experiment was carried out in a recirculated sea water system using 15 Pacific oysters (Crassostrea gigas) separated from each other and(More)
Azaspiracid (AZA) poisoning has been reported following consumption of contaminated shellfish, and is of human health concern. Hence, it is important to have sustainable amounts of the causative toxins available for toxicological studies and for instrument calibration in monitoring programs, without having to rely on natural toxin events. Continuous pilot(More)
Experimental PSP contamination of adult Pacific oysters (Crassostrea gigas) by the toxic dinoflagellate Alexandrium minutum Halim (120 cells.mL-1 continuously maintained in each flume) was carried out in a recirculated seawater system to obtain toxin levels above the safety threshold. In these conditions, 150 to 300 micrograms STX.eq.100 g-1 of shellfish(More)
Azadinium spinosum, a small toxic dinoflagellate, was recently isolated and identified as a primary producer of azaspiracid toxins (AZAs). Previous experiments related to AZA accumulation in blue mussels upon direct feeding with A. spinosum revealed increased mussel mortality and had negative effects on the thickness of the digestive gland tubules.(More)
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(More)
The relationship between azaspiracid shellfish poisoning and a small dinoflagellate, Azadinium spinosum, has been shown recently. The organism produces AZA1 and -2, while AZA3 and other analogues are metabolic products formed in shellfish. We evaluated whether mussels were capable of accumulating dissolved AZA1 and -2, and compared the toxin profiles of(More)
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