Cytotoxic, Acetylcholinesterase Inhibitor and Antioxidant Activity of Nepeta menthoides Boiss & Buhse essential oil

Abstract

Nepeta menthoides Boiss & Buhse (Lamiaceae) is a herbaceous aromatic plant endemic to North West Iran. It has been used for gastrodynia, insomnia, high blood pressure, bone pain and rheumatism in folk and traditional medicine. Essential oil of aerial parts was obtained by hydrodistillation and analyzed by GC-MS. The present work describes in vitro cytotoxic activity of the essential oil evaluated against HT-29 (colon carcinoma), Caco-2 (colorectal adeno-carcinoma), T47D (breast ductal carcinoma) and NIH-3T3 (Swiss mouse embryo fibroblast) cell lines using the MTT method. Acetylcholinesterase inhibitory effect of the oil was assessed by Mata method and their antioxidant activity measured by DPPH and FRAP assays. Twenty-one components representing 92.86 % of the total oil were identified. The major components were 4a-α,7β,7a-α-Nepetalactone (18.39 %), 4a-α,7α,7a-α-Nepetalactone (17.57 %), 1,8-cineol (16.66 %) and geranyl acetate (7.0 %). The MTT test showed a significant effect of the essential oil against all three cell lines (IC50 were 19.37±4.92, 30.7±7.36 and 32.24±5.98 µg/ml for T47D, HT-29 and Caco-2 cell lines respectively). In acetylcholinesterase inhibitory test, the essential oil had desirable activity with IC50 value of 64.870 µg/ml.IC50 of DPPH test and FRAP value were 28.363 µg/ml and 68.902±1.37 µmol Fe2+/g dry plant. These activities can be attributed to different components of N. menthoides essential oil and further experiments are necessary to investigate the main active compounds.