Hong-Nong Chou1*, and Chih-Yu Chen2, 1Institute of Fisheries Science, and 2Department of Zoology, National Taiwan University, Taipei, Taiwan 10617, Chinese Taipei
Abstract
Purple clams (Hiatula rostrata Lighttoot), which was fed with a toxic strain of the dinofagellate Alexandrium minutum Halim for study of accumulation of paralytic shellfish poisoning (PSP) toxins and subsequent study of toxin distribution during depuration (detoxification by a nontoxic microalgal diet or starvation). The results showed and confirmed the data in the literatures concerning the high toxicity of the digestive gland. It was also found the depuration efficiency between the toxic clams feeding subsequently with nontoxic microalgae and the ones put in starvation is similar. The toxin profile of the purple clams was similar with that of A. minutum at the end of the exposure period; GTX4 and GTX1 were dominant. However, at the end of the depuration period, GTX3 and GTX2 were dominant to show inconsistent removing rates of different toxins or a transformation of toxins occurred. However, no PSP toxins other than GTX-1, 2, 3 and 4 were detected in the experimental period. The non-visceral tissues were also found toxic after feeding with toxic algae. The toxicity was low and the profile was also similar with that of the toxic algae. The results concluded the fact of toxin translocation between tissues.
Key Words: Alexandrium minutum, gonyautoxins, paralytic shellfish poisoning toxins, Hiatula rostrata, depuration