Identification of Okadaic Acid As a Toxic Component of a Marine Dinoflagellate Prorocentrum lima

Abstract

Two diethyl ether soluble toxins (PL toxin-I, II) and one 1-butanol soluble toxin (PL toxin-III) were isolated from a benthic marine dinoflagellate Prorocentrum lima. The major toxic component, PL toxin-II, was purified by several steps of column chromatography to yield colorless crystals: mp. 156–158°C, [formula omitted]. Physical and chemical data pointed to a molecular formula C44H68O13 having four hydroxyls, one carboxyl, seven ether linkages, three olefins, and five methyls in the molecule. A further examination of its properties and a comparison with an authentic specimen established that PL toxin-II is identical with okadaic acid, recently isolated as a cytotoxic component of two sponges Halichondria okadai and H. melanodocia. © 1982, The Japanese Society of Fisheries Science. All rights reserved.