Investigation of the Antimutagenic Potentials of the Methanol Extract of Origanum vulgare L. subsp vulgare in the Eastern Anatolia Region of Turkey

The aim of this study was to evaluate the antimutagenic activity of the methanol extract of Origanum vulgare L. subsp. vulgare. Antimutagenic activity was estimated by employing the plate incorporation AMES/Salmonella histidine reversion assay. The base pair substitution tester strain Salmonella typhimurium TA1535 and the frame shift mutagen strain S. typhimurium TA1538 were used against direct acting mutagens - sodium azide (NaN(3)), 4-nitro-1-quinoline oxide (4NQO) and the S9-dependent mutagen 2-aminofluorene (2AF). The results suggested that in the absence of S9 metabolic activation, all 3 doses (5, 0.5, and 0.05 mu g/plate) of the plant extract tested caused statistically significant (P < 0.05) antimutagenic activity on TA-I 535 strain, but not on TA1538 strain. However, in the presence of S9 microsomal fraction, the plant extract exerted moderate antimutagenic activity against the 2AF mutagen and reduced mutant colonies in TA1535 and TA1538 strains. As a result, the methanol extract of Origanum vulgare subsp. vulgare showed antimutagenic effects at 5, 0.5, and 0.05 mu g/plate concentrations. These effects may be explained with the antioxidant activity mechanism, changes in membrane lipids, and permeability of ion channels.