Accumulation and Depuration of Yessotoxin in Two Bivalves
Contamination of bivalves with yessotoxins (YTXs) has been reported since 1987 in several coastal environments. In our study we investigated the accumulation and the metabolism of YTXs in 2 bivalve species important to German fisheries and aquaculture. Mussels and oysters, Mytilus edulis and Crassostrea gigas, were exposed to the YTX-producing dinoflagellate Protoceratium reticulatum isolated from the North Sea. Toxin profiles from algae and bivalves were analyzed by liquid chromatography with tandem mass spectrometry (LC-MS/MS). It was evident that 45-hydroxy YTX (45-OH YTX), carboxy YTX (COOH YTX), and the putative 45-hydroxy-carboxy YTX (45-OH-COOH YTX) were the dominant YTX analogues in M. edulis. The oyster C. gigas displayed a different toxin profile. YTX, 45-OH YTX, and 45-OH-COOH YTX were also present, but COOH YTX was not detectable. Furthermore, 2 unidentified analogues with the same MS/MS transition ([M-H] > [M-H-SO3]) occurred in both bivalve species. Homo YTX and 45-hydroxy-homo YTX, which are regulated together with YTX and 45-OH YTX in 2002/225 EC were not detected. In general, we confirmed former field investigations on accumulation and metabolism of YTXs in M. edulis; however, this is the first study on accumulation and metabolism of YTXs in the oyster C. gigas.
Helmholtz Research Programs > PACES I (2009-2013) > TOPIC 2: Coastal Change > WP 2.1: Food Webs and Diversity under Global and Regional Change