Essential Oil Polymorphism of Thymus pannonicus All. (Lamiaceae) in Serbia

Three populations of Thymus pannonicus grown in Serbia (one from northern and two from east Serbia) were examined for chemical composition of their essential oil. Thymus pannonicus is used in traditional medicine and it is collected by local people in the studied regions, hence the interest in composition of its essential oils. Three major groups of essential oil components were identified, such as monoterpene hydrocarbons, oxygenated monoterpene hydrocarbons and sesquiterpene hydrocarbons. Each of investigated populations showed its own chemotype, including: geranial (citral), alpha-pinene and germacrene-D. To best of our knowledge, this sesquiterpene hydrocarbon was reported as a major component in Thymus bracteosus only. In these populations the phenolic compounds thymol and carvacrol, considered as most frequent constituents of essential oil in Thymus taxa, haven't been found in significant quantities