Essential oil composition of Turkish mountain tea (Sideritis spp.)

The essential oil components of aerial parts from Sideritis bilgerana, Sideritis tmolea and Sideritis congesta were investigated by GC and GC-MS. The oil yields of dried plants obtained by hydro-distillation were 0.26, 0.33 and 0.83 (v/w), respectively. Fifty compounds representing 94.6% of the S. bilgerana oil were identified. The main ones were beta -pinene (51.2%) and alpha -pinene (30.2%). Thirty-six components, representing 79.7% of the S. congesta oil were determined with high contents of muurol-5-en-4-a-ol (11.7%) and muurol-5-en-4-b-ol (33.0%). Fourty-four components were identified accounting for 89.6% of the S. tmolea oil. Major constituents were alpha -cadinol (21.9%), beta -caryophylene (10.6%), calamenene (7.05%), muurrol-5-en-4-b-ol (7.05%) and alpha -pinene, (5.1%). All oils consist of monoterpenic hydrocarbons, oxygenated monoterpenes and sesquiterpenes. Muurol-5-en-4a-ol and muurol-5-en4-b-ol, at high percentages, were distinct components of S. congesta. (C) 2001 Elsevier Science Ltd. All rights reserved.