DIFFERENTIAL PROTECTIVE EFFECTS OF ANTIOXIDANTS AGAINST CELL KILLING AND MUTAGENESIS OF SALMONELLA-TYPHIMURIUM BY GAMMA-RADIATION

A commercial mixture of phenolic antioxidants containing BHA, BHT and PG, commonly used in the food industry, was found to protect Salmonella typhimurium against killing and induction of his+ mutations by γ radiation. The protective effect was apparent only when irradiotion was performed in the presence of oxygen and no protection could be detected in its absence. When each of the components of the antioxidant mixture was tested separately, only PG displayed a protective effect. The amount of protection provided by the mixture of antioxidants was close to the protection afforded by hypoxia. Also, protection against cell killing was very similar in magnitude to protection against induction of mutations. The protective effect could be detected only when antioxidants were added to the cells before irradiation. No protection was afforded upon addition immediately after irradiation. © 1981 Oxford University Press. All rights reserved.