Essential Oil Content and Composition of Thymus migricus Klokov & DesjShost. Affected by Plant Growth Stage and Wild Habitat Altitude

摘要

Essential oil content and composition of air dried aerial parts of wild growing Thymus migricus Klokov. & Desj-Shost. plants were evaluated in response to different phenological stages (pre-flowering or vegetative, flowering and post-flowering stages) and wild habitat altitude (2000 and 2100m above mean sea level). The results revealed that the highest essential oil content (0.34%) belonged to the flowering stage at 2000m altitude. GC and GC/MS analysis of volatile oils showed that α-terpineol (3.4-21.8%), thymol (3.4-19.4%), 1,8-cineol (1.9-14.5%) and carvacrol (2.5-16.1%) were the major oil components. However, carvacrol was determined in plant samples from 2000m altitude during vegetative stage. Geranial (3.5-12.4%), geranyl acetate (2-10.8%), borneol (1.4- 8.3%), geraniol (0.5-8.3%), p-cymene (1.8-8.1%), and camphor (0.7-6.7%) were the other major oil components with scattered distribution between treatment combinations. Taking into account the essential oil content, it seems that flowering stage at 2000m altitude was the most appropriate harvest stage for this plant from its wild habitat. α-Terpineol proportional percentage was the highest during vegetative and full-flowering stage.