Abstract
Marine toxins occurring in lipid fractions are responsible for three types of seafood poisoning : diarrhetic shellfish poisoning (DSP), neurotoxic shellfish poisoning (NSP), and ciguatera fish poisoning. The major toxins in DSP, okadaic acid and its derivatives, originate from the dinoflagellates Dinophysis spp. The toxins inhibit protein phosphatase 2 A and are potent tumor promotors. Brevetoxins implicated in NSP are produced by the dinoflagellate Gymnodinium breve. The toxins are characterized by contiguous ether rings arranged in a laddershape. Ciguatoxins responsible for ciguatera originating from the dinoflagellate Gambierdiscus toxicus are also bear a ladder-shaped cyclic ether skeleton. Both brevetoxins and ciguatoxins potentiate voltage gated Na channels. All these toxins are highly oxygenated, extremely toxic, and possess high molecular weights. Chemical and biochemical methods for determining the toxins are described.
