Fungal melanin pigments were shown to display a high antioxidant activity. An increase in the number of methyl substituents in benzidine molecules of melanins obtained from micromycetes and macromycetes was accompanied by a decrease in the efficiency of inhibition of peroxidase-catalyzed oxidation. Melanins were found to have considerable gene-protecting properties. Pigments isolated from macromycetes and applied at a much lower concentration than those obtained from micromycetes prevented damage to bacteriophage-lambda DNA induced by products of peroxidase-catalyzed degradation of aminobiphenyls.