[Proteolytic destruction of a hemorrhagic toxin from the venom of the habu (Trimeresurus flavoviridis)].

The major hemorrhagic principle (HR1B) in the venom of Habu (Trimeresurus flavoviridis), a crotalid, was found to be easily inactivated and hydrolyzed by a commercial protease (Nagarse). The ability of the hydrolysate to produce the toxin-neutralizing antibody has been shown to be comparable to or superior to those of two formol toxoids used as the controls, suggesting that inactivation of HR1B by the protease provides a new method for the preparation of Habu toxoid.