Abstract: Gymnodimine (GYM), an algal toxin first detected from New Zealand oyst
ers in 1994, is identified as a cyclic imine toxin and produced by Karenia sel
liformis, with imino nitrogen attached on loop-coil. Imine is the poisonous f
unctional group of the toxin. GYM has a low oral toxicity, but its acute lethal
toxicity of intra-peritoneal injection for mice is very high. Up to now, few re
ports have been published on the detailed information about the toxicity mechani
sm of GYM. Based on limited literatures, this paper reviewed the GYM’s structure
, producer, toxicity mechanism, carrying animals, geological distribution, degra
dation metabolism, dose-effect relation, and risk evaluation, and proposed the
further research directions on algal toxin.

Key words: gymnodimine, toxicity, distribution, risk evaluation, Sclerodermus sichuanensis Xiao, paralysis, bacteriostasis, melanization.