INHIBITION OF THE BACTERIAL MUTAGENICITY OF N-METHYL-N'-NITRO-N-NITROSOGUANIDINE BY ASCORBIC-ACID AND ASCORBYL PALMITATE

The mechanism of antimutagenic activity of ascorbic acid (AA) and its derivatives was studied using the Salmonella typhimurium TAIOO bacteri al test system. All substances studied inhibited N-methyl-N'-nitro-N-n itrosoguanidine (MNNG)-induced mutagenesis. Ascorbyl palmitate (AP) ma rkedly decreased the numbers of his' revertants, behaving as a membran e-active antimutagen. A comparative study of the antioxidative activit y of the investigated substances in the methyl oleate (MO) system has demonstrated that AA and its derivatives have pro-oxidant properties w ithin the limits of the concentrations studied. The results obtained d o not agree with the common view of the mode of action of these antimu tagens, including both inhibition of free radical processes and MNNG r eductive inactivation.