Confirmation of yessotoxin and 45,46,47-trinoryessotoxin production by Protoceratium reticulatum collected in Japan.

Two different strains of the dinoflagellate Protoceratium reticulatum collected at Harima Nada and Yamada Bay in Japan were cultured and analyzed by fluorometric HPLC for yessotoxin production. Only the Yamada Bay strain produced yessotoxin. The toxin together with its analog, 45,46,47-trinoryessotoxin, were isolated from larger scale culture and unambiguously confirmed by (1)H NMR and MS measurements. This is the first confirmation of the biogenetic origin of yessotoxin in Japan, where the toxin was first reported. The results also indicate that the production of yessotoxins by P. reticulatum differs from strain to strain, in a similar way to that observed in many other toxigenic dinoflagellates such as Dinophysis spp. and Alexandrium spp.