Effects of Thymus revolutus Celak essential oil and its two major components on Hep G2 cells membrane

In this study pro/anti-oxidant activities of Thymus revolutus C,lak (T. revolutus C.) essential oil and its two main components on Hep G2 cells were determined. Twelve components were identified in T. revolutus C. essential oil by GC and GC-MS and the main components of the oil were cymene (32.57%) and gamma-terpinene (17.18%). The essential oil showed more cytotoxicity than its two main components on Hep G2 after 24, 48 and 72 hours incubations. Membrane damage effects of the essential oil and its two main components on Hep G2 cells were increased by incubation with IC10, IC50 and IC70 concentrations. Lower essential oil (< IC50) concentrations had cytoprotective and membrane protective effects against H2O2. The free radical scavenging activity of the essential oil of T. revolutus C. (EC50 = 250 +/- 0.2 mu g/mL) was superior to its two main components (neither not active). Oxidation of linoleic acid was effectively inhibited by T. revolutus C. (72.8%), while inhibition values of linoleic acid oxidation were calculated as 23.4.% and 26.7% for cymene and I"-terpinene, respectively. These findings suggest that essential oils and its two main components had both pro-oxidant and protective (antioxidant) effects and they exhibited those effects depending on concentration.