Okadaic acid shellfish-derived

Three classes of polyethers, okadaic acid derivatives, pectenotoxins, and yessotoxin were isolated from bivalves in connection with diarrhetic shellfish poisoning. The etiology of the toxins, toxicological properties, and determination methods are described. 

The toxins responsible for DSP include a series of polyether molecules (including okadaic acid and six derivatives of dinophysistoxin), four pecteno-toxins (polyether lactones), and yessotoxins (including two sulfate esters that resemble brevetoxins) (Murata, 1982 Murata, 1987 Tachibana et al., 1981 Yasumoto, 1989). Diarrhetic shellfish poisons are produced primarily by dinoflagellates from the genera Dinophysis, although Prorocentrum lima also produces both okadaic acid and dinophysistoxin-1 (Heredia-Tapia et al., 2002). 

Protein phosphatases inhibitors. Okadaic acid from marine dinoflagellates that accumulates in a black sponge (Halichondria okadal) and mussels, is a polyether fatty acid derivative. It causes a contracture of smooth and cardiac muscle, is a tumour promoter and selectively inhibits protein phosphatase-1 and phosphatase-2A. It is a causative agent in diarrhoretic shellfish poisoning. 

Structure, nomenclature and occurrence The group of marine toxins known as azaspiracids (AZA) was only recently discovered to be the cause of shellfish poisoning in humans. Their source is the algae of the genus Protoperidinium. Azaspiracids are a group of polyethers (such as okadaic acid), but they contain a nitrogen heterocyclic amine piperidine (10-246). About 20 different derivatives have... 

Li et al., 2010). Toxic to mice (by intraperitoneal administration), pectenotoxins have low oral toxicity and poisoning by shellfish containing them would actually be due to okadaic acid or okadaic acid derivatives, which are often associated with pectenotoxins (Miles et al, 2004a Blanco, Alvarez, and Uribe, 2007 Miles, 2007 Torgersen et al, 2008). The mode of action of pectenotoxins is still... 

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