| The red tide dinoflagellate Pyrodinium bahamense Plate var. compressum Bohm is the causative organism responsible for most paralytic shellfish poisoning (PSP) events in the tropical Pacific. Little information is available on the physiology and toxin production characteristics of P. bahamense due to failures in establishing laboratory cultures. In this study, a P. bahamense isolate from Malaysia was successfully cultured in a modified version of Provasoli's enriched-seawater medium. Typical culture yields were 5000-6000 and 1500-2000 cells mL;Analysis by high performance liquid chromatography showed that the isolate produced saxitoxin, neosaxitoxin, decarbamoyl-saxitoxin, and gonyautoxins 5 and 6. Neosaxitoxin and gonyautoxin 5 comprised 30 mole percent or more of the total toxin content (measured in fmol cell;Pyrodinium bahamense is a fastidious species to culture and the optimum culture medium for the species has yet to be determined. It was evident that growth conditions significantly affected toxin production in the species. Toxin production in P. bahamense showed several similarities to production in Alexandrium spp. and Gymnodinium catenatum, but there were also significant differences. |
