Amphitoxin, a New High Molecular Weight Antifeedant Pyridinium Salt from the Caribbean Sponge Amphimedon compressa

Abstract

A new polymeric pyridinium alkaloid named amphitoxin [2] has been isolated from Amphimedon compressa, and its structure determined by spectroscopic analysis. In laboratory feeding experiments, crude extracts and purified amphitoxin [2] from A. compressa at lower than natural concentration levels effectively deterred feeding of a generalist predatory Caribbean reef fish, Thalassoma bifasciatum.