COMPARATIVE-STUDY ON PARALYTIC SHELLFISH TOXIN PROFILES OF THE DINOFLAGELLATE GYMNODINIUM-CATENATUM FROM 3 DIFFERENT COUNTRIES

Paralytic shellfish toxin profiles of the dinoflagellate Gymnodinium catenatum Graham were investigated as a possible biochemical marker to distinguish different geographic populations of this species. Isolates obtained between 1986 and 1988 from Japan, Tasmania (Australia) and Galicia (Spain) were cultured under similar conditions and the toxins produced were analyzed using HPLC. Variations in temperature, salinity, and nitrate and phosphate levels in the culture medium had no significant effect on the toxin profile, suggesting that toxins can be used as a stable biochemical marker for this dinoflagellate. All the isolates produced mainly toxins of the N-sulfocarbamoyl group (C1-C4, gonyautoxins 5 and 6) but their relative abundance differed according to their geographic origin. Furthermore, only the Australian population produced the newly found 13-deoxydecarbamoyl toxins, and these could readily be used to distinguish the Australian populations from those of the other two countries.