Occurrence of a Tetrodotoxin-like Compound as a Minor Toxin in the Puffer Fish, Fugu flavidus

抄録

Toxins in ovaries and livers of the puffer fish, Fugu flavidus, were purified successively on activated charcoal, Bio-Gel P-2 and Bio-Rex 70. Besides tetrodotoxin (TTX), a minor toxin (toxin D) was newly detected in both tissues; toxin D accounted for 3% and 4% of the toll lethal potency in ovaries and livers, respectively. Although there were differences in the specific lethal activity, dose-survival time relation and signs in mice between toxin D and TTX, positive reactions to Weber reagent and 10% KOH, and a negative one to 1% H₂O₂ were observed for both toxins. Moreover, toxin D, like TTX, gave rise to the C₉-base upon alkali-degradation. These results suggested that toxin D is a TTX-like compound having a quinazoline skeleton.