Abstract:This research was performed to control the antioxidant activity, mutagenicity and antimutagenic effect of Mentha longifolia (L.) ssp. longifolia essential oil (EO), which is considered as a possible ingredient when producing healthy food. The antiradical activity was established using DPPH (2,2-diphenyl-1-picrylhydrazyl radical) and β-carotene/linoleic acid bleaching assays. The total phenolic content in the EO was evaluated by Folin Ciocalteau method (FCR). Ames Salmonella/microsome mutagenicity assay was applied to detect possible mutagenic and antimutagenic behavior. Our observations reveal that the IC50 value for DPPH radicals was 5.27 ± 0.13 mg/mL. The total antioxidant efficiency increased with an increase in the concentration of the EO, and IC50 value 11.7 ± 0.21 mg/mL. The total of phenolics was 186 ± 8.9 mg/g gallic acid equivalent/EO. Also, any concentrations of the EO used did not show mutagenic action but exhibited strong antimutagenic effects at 10.0-4.0 µg/plate concentrations. This research proposes that because of the antioxidant and antimutagenic characteristics, the EO is very advantageous and significant to the company's manufacturing food additives.