Effect on fishes of two toxic polypeptides isolated from Anemonia sulcata

The effects of two toxic polypeptides isolated from Anemonia sulcata Pennant (Anthozoa) were tested on Gadus morhua, Pleuronectes platess and Platichthys flesus. In tramuscular injections caused paralysis and death, with symptoms similar to those of death caused by lack of oxygen. In cod, the LD₅₀ dose of Toxin II was 50 times higher chan that of Toxin I (Toxin I=6.9 mg/kg, Toxin II=0.14 mg/kg). Flatfish were less sensitive. The LD₅₀ of Toxin II was 0.37 mg/kg for Platichthys flesus and 0.38 mg/kg for Pleuronectes platessa. Both toxins are less lethal to fishes than to crustaceans.