Occurrence of tetrodotoxin in the gastropod mollusk Natica lineata (lined moon shell)

Paralytic toxicity was detected in 28 of 38 specimens of the gastropod mollusk Natica lineata (lined moon shell). The highest toxicity, expressed as tetrodotoxin (TTX), was 720 mouse units per gram (MU/g) muscle, followed by other parts which included salivary gland, brain and mouth organs (28 MU/g) and digestive gland (12 MU/g). The toxin was partially purified by ultrafiltration and Bio-Gel P-2 column chromatography. The toxin showed a specific toxicity (as TTX) of 620 MU/mg. Results of analyses by thin layer chromatography, cellulose acetate membrane electrophoresis and high performance liquid chromatography showed that the toxin was composed of TTX and anhydrotetrodotoxin. This is the first time that TTX and its related substance have been found in this species of gastropod.