Chemical Composition and Antioxidant Activities of Leaf and Flower Essential Oils of Origanum onites L. (Lamiaceae) Growing in Mount IdaTurkey

Abstract

The chemical composition of leaf and flower essential oils of Origanum onites L. were analyzedusing Thermo Scientific TSQ GC-MS/MS. Also, antioxidant activities of the leaf and flower essential oilswere investigated by using DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging activity and βcarotene linoleic acid assays. BHA (Butylated hydroxyanisole) and BHT (Butylated hydroxytoluene) wereused as standards. The essential oil yields of O. onites were 1.75% for leaves and 4.25% for flowers. Atotal of twenty-three compounds representing 99.9% of leaf oil and twenty-four compounds constituted99.6% of the flower oil were determined. Oxygenated monoterpenes were detected at a high percentage(69.2%) in leaf essential oil, and carvacrol (64.9%) was determined as the main compound. Also, floweressential oil was dominated by sesquiterpene hydrocarbons (73.5%), and α-cubebene (36.4%) wasdetermined as a primary compound. For leaf oil, a high antioxidant capacity was determined, primarilydue to carvacrol and p-cymene.