Okadaic acid production from the marine benthic dinoflagellate Prorocentrum arenarium Faust (Dinophyceae) isolated from Europa Island coral reef ecosystem (SW Indian Ocean).

Okadaic acid was isolated from a strain of Prorocentrum arenarium Faust (Prorocentrales, Dinophyceae) collected from Europa Island (40 degrees 22'E, 22 degrees 20'S, SW Indian Ocean). The presence of okadaic acid in the algal extract was suspected after cytotoxicity and phosphatase 2A inhibition testing. It was confirmed by ADAM derivatization, immunoaffinity extraction and liquid chromatography with fluorimetric detection analysis as well as by liquid microchromatography with mass spectrometric detection. Results indicate that the P. arenarium strain was toxinogenic and could be potentially involved in the toxin production associated with the human diseases, diarrhetic shellfish poisoning and possibly ciguatera fish poisoning in the SW Indian Ocean area.