First examination of sterols in the marine dinoflagellate genus Vulcanodinium.

Vulcanodinium is an ecologically relevant dinoflagellate genus due to its production of neurotoxins known as pinnatoxins. We present here the first examination of the sterols of a Vulcanodinium rugosum isolate. Sterols are ringed lipids that assist in maintaining rigidity of cellular membranes, and the Dinophyceae are well-studied for their ability to produce a diverse array of sterols, many of which have chemotaxonomic utility. We have determined that V. rugosum produces a set of major sterols, namely cholesterol, dinosterol, 4α,24-dimethyl-5α-cholest-22E-en-3β-ol, and 4α,24-dimethyl-5α-cholestan-3β-ol, common to the Dinophyceae. However, this displayed marked differences from those studied members of the genera Scrippsiella and Peridinium, the closest phylogenetic relatives. Included in these differences is production by V. rugosum of a much lower percentage of dinostanol, a saturated form of dinosterol.