Essential oil Screening and antioxidant activity of Satureja bachtiarica Bunge. population in Ilam Province for Isolation of Promising Chemotypes

This work carried out in order to evaluating of oil yield, phytochemical variation and antioxidant activity of essential oils in different populations of Satureja bachtiarica Bunge. In west of Iran. So the aerial parts of eight wild populations of this plant were collected from different regions of Ilam, Gilane-Gharb provinces and one sample was collected in greenhouse of Ilam University, during 2010 and 2011. The essential oils were obtained by hydro distillation method, were analyzed by GC/MS and the antioxidant activity of them were measured by DPPH assay. The analysis were showed that the populations had significant differences regarding yield, phytochemical composition and their antioxidant activity. Maximum and minimum oil yield were recorded from Shalam and Greenhouse populations, respectively. The main components of plant oil were thymol (39.28-87.30%), p-cymene (0.15-30.63%), γ-terpinene (2.04-14.71%) and carvacrol (0-8.41%). The Shalam population had the highest phytochemical diversity and then the Shalam, Soregeh, KabirKooh and Ghalaarang populations were the most similar populations according to their phytochemical composition. Cluster analysis of populations, which using Ward Algorithm were divided them into three chemotypes. The highest and lowest total phenols contents were recorded in Ghalaarang (292.5±0.91 mg Pyrocatechol/ml) and Gerdakaan (194.04 ±1.08 mg Pyrocatechol/ml) population, respectively. The antioxidant activity of these populations varied from 59.1±0.9 to 73.8±0.45 % in Green house and Badreh, respectively .The Shalam population had the highest (IC50=0.67 mg/ml) in comparison with synthetic antioxidant BHT (0.11 mg/ml). In cluster B including populations of Soregah, Ghalaarang, Shalam, KabirKooh, Renou, and Badreh were remarked for further domestication processes.