Busk L, Ahlborg U G
Toxicol Lett. 1980 Sep;6(4-5):243-9. doi: 10.1016/0378-4274(80)90127-7.
Vitamin A (retinol) was shown to inhibit the mutagenic activity of aflatoxin B1 (AFB1), when added to the Ames Salmonella/mammalian microsome assay. The inhibition was dose-dependent and not caused by a direct toxic effect on the test bacteria. On the other hand the mutagenicity of diepoxybutane, a mutagen not requiring metabolic activation, was not affected by retinol, indicating that the vitamin does not act as a general scavenger of reactive compounds. The mutagenicity of AFB1 depends on the balance between formation and breakdown of aflatoxin 2,3-epoxide, the presumed ultimate mutagenic/carcinogenic metabolite. Inhibition of AFB1 mutagenicity could thus result from decreased formation or increased breakdown of the 2,3-epoxide.
