Inhibition of protein pyrolysate mutagenicity by retinol (vitamin A).

The mutagenicity in the Ames Salmonella-microsome test of four protein pyrolysate products, formed during the cooking of meat, (Trp-P-1, Trp-P-2, Glu-P-1 and Glu-P-2) was found to be inhibited by the addition of vitamin A in vitro in the form of retinol. The effect is interpreted as an inhibition of the metabolic activation of the mutagens to their respective ultimate mutagenic forms since retinol has been shown to have no effect on the survival of the Salmonella cells, no effect on directly acting mutagens and no effect on the formation of NADPH in the test system. The results demonstrate the need for an increased understanding of the interaction of dietary components in evaluating mutagenic/carcinogenic risks from processed food.