摘要：A chemical carcinogen, ethyl carbamate (urethane), has been shown to be a contaminant of various alcoholic beverages. The condition of ethyl carbamate formation from cyanide via cyanate and the method of its prevention method with a cyanide metabolizing enzyme, bovine liver rhodanese, were studied using a model solution of alcoholic beverage. Ethyl carbamate was not formed from thiocyanate or cyanuric acid, but from cyanate ; it was also formed from cyanide in the presence of diacetyl or cupric ion. The formation from cyanate was accelerated in higher temperature and at lower pH, but was prevented by di- or tribasic acid. 2-Aminobenzoic acid inhibite the formation from cyanate, cyanide, urea and carbamoyl phosphate, and these results suggest that cyanate is the genuine intermediate of ethyl carbamate formation from cyanide, urea and carbamoyl phosphate, Sulfite which is used for an antioxidant in wine did not inhibit the ethyl carbamate formation. In addition, the formation of ethyl carbamate from cyanide with diacetyl was inhibited one-fifth by pretreatment with rhodanese, at neutral pH range.
