Okadaic acid, diarrheic shellfish poisoning

Kumagai, M., et al., Okadaic acid as the causative toxin of diarrheic shellfish poisoning in Europe, Agric. Biol. Chem., 50, 2853, 1986. 

Finally, it is necessary to underline the versatility of the approach. By selecting the appropriate enzyme, biosensors for other toxins can be developed. In this direction, our group has started the development of an enzyme sensor for okadaic acid, a marine toxin produced by toxigenic dinoflagellates and implicated in the diarrheic shellfish poisoning (DSP). 

Diarrheic Shellfish Poisoning (DSP). Human poisonings were first identified in the 1960s. It causes sickness in humans lasting several days but is not fatal. It is caused by chemicals of the okadaic acid family (okadaic acid+ 4 related compounds) produced by several species of Dinophysis dinoflagellates. The main contamination problems include mussels, clams, and other bivalves of the cold and warm temperate areas of the Atlantic and Pacific Oceans, mainly in Japan and Europe. Only two cases of DSP have been documented in North America. 

Diarrheic shellfish poisoning caused by okadaic acid is a gastrointestinal illness without chronic se-quellae. There is no evidence of neurotoxicity and no fatal cases have ever been reported. Diarrhea is the most commonly reported symptom, closely followed by nausea and vomiting with onset 30 min to 12 h from ingestion of contaminated shellfish. Complete clinical recovery is seen even in severe cases within 3 days. DSP has been reported predominantly in Japan and Europe. The toxin has also been isolated from P. lima cultures from the Gulf of California, Mexico. The incidence of DSP in this location as a result of this is unknown. 

Tripuraneni, J. et al.. The toxin of Diarrheic Shellfish Poisoning, okadaic acid, increases intestinal epithelial paraceUular permeability, Gastroenterol., 112, 100, 1997. 

Okadaic acid is produced by R lima (Murakami et al. 1982), R concavum (Dickey et al. 1990 Juranovic and Park, unpublished data) and G. toxicus (Juranovic and Park, unpublished data). This and other structurally related compounds have been implicated in DSP (diarrheic shellfish poisoning), most... 

An electrochemical immunosensor was fabricated by Barthelmebs et al. where okadaic acid (OA) (a biotoxin whose intoxication is considered one of the most worried diarrheic shellfish poisoning for human health) was immobilized upon graphitic working electrode, which is so employed as transducer surface via the reaction between diazonium coupling and graphite surface, as shown in Fig. 4. 

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