Purification of the ichthyotoxic component of Gymnodinium breve (red tide dinoflagellate) toxin by high pressure liquid chromatography

Abstract

High pressure liquid chromatography of a chloroform extract of the red tide dinoflagellate, Gymnodinium breve, was used to separate the ichthyotoxic component from the hemolytic and non-toxic fractions. The best separation was achieved by gradient elution with an increasingly polar mixture of chloroform and methanol through a micro particle silica column. Unlike preparative TLC, high pressure liquid chromatography achieved approximately 100-fold purification of G. breve toxin as determined by a probit analysis of dose-survival curves of its ichthyotoxicity. It was found that the purified toxin was unstable when stored in the dark at 4°C in the dry state as judged by its chromatographic behavior and u.v. and fluorescence spectra. The results of these analyses indicate that G. breve toxin contains a single ichthyotoxic component.