Abstract
Analysis of head space volatiles (HSV) and hydrodistilled essential oils (EO) of the above-ground parts of Thymus glabrescens Willd., T. praecox Opiz subsp. jankae (Celak.) Jalas (from two localities) and T. pulegoides L. was made by GC-FID and GC-MS. This is the first report on the headspace volatiles composition of T. glabrescens and T. pulegoides. The most abundant compound of T. glabrescens HSV was p-cymene (27.8%) followed by γ-terpinene (18.4%), while thymol (55.4%) and geraniol (10.5%) were the most abundant in the corresponding EO. T. praecox subsp. jankae EO from Serbia was characterized by (E)-caryophyllene (14.6%) and thymol (10.7%), which is substantially different from that of Bulgarian T. praecox subsp. jankae, which contained α-terpinyl acetate (20.1%) and linalool (17.7%) as its main components. The dominating components of the Serbian and Bulgarian T. praecox subsp. jankae HSV were α-pinene (29.4% and 18.6%, respectively), myrcene (12.1% and 23.2%, respectively), limonene (7.5% and 17.8%, respectively) and β-pinene (11.7% and 7.6%, respectively). Linalyl acetate predominated in T. pulegoides EO and HSV, representing 40.0% and 42.4% (respectively) of the total peak area. The chemical composition of the essential oils of the examined Thymus species could not be attributed to any particular recorded chemotype of T. glabrescens, T praecox and T. pulegoides.