Study on the mutagenicity of brandy with the Ara test.

The forward mutation assay to L-arabinose resistance (Ara test) in Salmonella typhimurium was used to demonstrate that evaporated residues of brandy had direct-acting mutagenic activity. The mutagenicity covered a 100-fold range, from 13482 to 127 AraR induced mutants/ml brandy equivalent. Rat liver S9 mix suppressed the mutagenic activity of brandy in the Ara test. The inactivating capacity was independent of microsomal monoxygenase enzymes and appeared to be mediated through a heat stable component of the S9 fraction. Catalase was identified as the putative S9 component responsible for its inactivating capacity. The implication of reactive oxygen species in the direct-acting mutagenicity of brandy was supported by the higher sensitivity of Escherichia coli bacterial strains deficient in two major cellular antioxidant defense (glutathione and/or catalase) compared to their parental wild-type. Phenolic compounds of a polar nature could be responsible for the mutagenicity through the production of reactive oxygen intermediates. Non-matured beverages (gin and non-matured rum) were non-mutagenic. It is conceivable that mutagenic phenolics might be extracted from the wood during maturation in the barrel. Autoxidation of phenolic compounds could be a common mechanism in the mutagenicity of complex mixtures of plant origin.