Effect of phenolic antioxidants on the mutagenicity of aflatoxin B1

Abstract

The Ames assay employing Salmonella typhimurium TA 100 and TA 98 was used to investigate potential interactions between aflatoxin B1 (AFB1) and butylated hydroxytoluene, butylated hydroxyanisole and propyl gallate phenolic antioxidants which are used to prolong the shelf-life of food. AFB1 doses were within the linear response range, and the antioxidants were used at levels of 0-50 .mu.g per plate. All 3 antioxidants were nonmutagenic in either bacterial tester strain, with or without the rat hepatic S-9 enzyme preparation; toxic effects were observed at doses > 20 .mu.g/plate. Butylated hydroxytoluene and butylated hydroxyanisole substantially increased AFB1-induced mutagenesis in the 2 tester strains with microsomal activation. The addition of 5-20 .mu.g of butylated hydroxytoluene or hydroxyanisole to 5-20 ng of AFB1 per plate caused more than a 2-fold increase in the number of His+ revertants. Addition of propyl gallate resulted in only a moderate increase in the number of revertants. Whereas several anticarcinogenic and antimutagenic effects by phenolic antioxidants have been reported, particularly in studies with polycyclic aromatic hydrocarbons, the enhancement of mutagenic potency of AFB1 by these compounds suggest a specificity with respect to the chemical nature of AFB1. [Human applicability is implicit].