Abstract

Zare Reza and Reza E. S

Thymus kotschyanus Boiss. & Hohen. is a grassy, permanent herb which belongs to Labiatae family and grows wild in some regions of Iran including West Azarbaijan province. In this study, variations in the quantity and quality of the essential oils of wild and cultivated populations of T. kotschyanus are reported. The aerial parts of T. Kotschyanus at the beginning of flowering stage (20% flowering) were collected from provenance and agriculture research field. The essential oils were extracted in a Clevenger apparatus by using hydro-distillation method. Results show that the essential oil in the provenance and cultivated Thymus were obtained by hydro-distillation at yield of 0.91, 1.43 and 1.72% (based on v/w), respectively. The essential oils were analyzed by GC/MS. In the provenance plants (T.k-W1), (T.k-W2) 20 components, making up 99.49 and 96.69% of the oils respectively, were identified. The major components of the essential oils in the plants T.k-W1 were Thymol (43.83), Carvacrol (22.11), and Terpinene (19.73%). And in T.k-W2, major components of the essential oil were carvacrol (29.39), cineol (11.95), thymol (8.48) and α-terpieol (6.29%). In the essential oils of the cultivated Thymus, the main components were Thymol (51.79), Terpinene (12.31), Comphene (7.06), α-terpieol (6.83) and Carvacrol (6.69%). Also, in the present study, the antioxidant activity of T. kotschyanus essential oils was determined using DPPH radical scavenging assay.