MUTAGENICITY OF ETHYL-1,2,3,4-TETRAHYDRO-BETA-CARBOLINE-3-CARBOXYL ACID-TREATED WITH NITRITE IN THE PRESENCE OF ALCOHOLS

The mutagenicity of a product produced from hyl-1,2,3,4-tetrahydro-bet a-carboline-3-carboxylic acid (MTCCA), which is a component in soy sau ce, after treatment with 50 mM nitrite at pH 3, 37 degrees C, for 60 m in in the presence of 7.5%, ethanol was much higher than that in the a bsence of ethanol during the nitrite treatment. The enhancement of the mutagenicity of nitrite-treated MTCCA by ethanol required simultaneou s treatment of MTCCA with nitrite and ethanol. The mutagenicity of MTC CA treated with nitrite in the presence and absence of ethanol was det ected in the same fractions on HPLC and was highest for Salmonella typ himurium strain YG1029 possessing elevated O-acetyltransferase activit y among the several Salmonella test strains, suggesting that the same mutagen belonging to aromatic compounds was produced both in the prese nce and absence of ethanol. Methanol, n-propanol and isopropanol as we ll as ethanol were also observed to have an augmenting effect. However , the sugars glucose and sucrose had no effect. When MTCCA was treated with nitrite in the presence of commercial alcoholic beverages equiva lent to 1.25-10% ethanol, Japanese 'sake' and 'shochu' were demonstrat ed to have a highly augmenting effect and beer, wine, whisky and brand y to have a mildly augmenting effect.