Toxins Produced by Benthic Dinoflagellates

Nine species of benthic dinoflagellates collected in subtropical waters were cultured, extracted, and tested for mouse lethality, ichthyotoxicity, and hemolytic activity. Hemolytic activity was detectable in all species, but the activities of Amphidinium carteri, A. klebsi, and Gambierdiscus toxicus were outstanding. G. toxicus showed the most potent mouse lethality. Two hemolytic constituents of A. carteri were determined to be mono- and di-galactoglycerolipids. Maitotoxin, produced by G. toxicus, was suggested to have a molecular weight of 3402 ± 2 (m/z). Two potent toxins against mice were isolated from Prorocentrum lima and identified as okadaic acid and 5-methylene-6-hydroxy-2-hexen-1-okadaate.