The Essential Oil Compositions of Teucrium spp. Belonging to the Section Polium Schreb. (Lamiaceae) Growing in Cyprus

The genus Teucrium L., belonging to the family Lamiaceae, is divided in ten sections including Polium (Mill.) Schreb. In Cyprus, this section is represented by five endemic species: T. micropodioides, T. cyprium, T. karpasiticum, T. kyreniae and T. salaminium. Essential oils of the aerial parts of these species were separately obtained by hydrodistillation using a Clevenger-type apparatus. Chemical compositions of the obtained oils were analyzed by GC and GC/MS, simultaneously. The essential oil yields ranged between 0.03-0.75 (v/w). The major components of the essential oil of T. kyreniae were β-caryophyllene (21.2%), (Ε)-nerolidol (10.9%), carvone (8.8%) and α-humulene (7.9%). T. salaminium essential oil was dominated by β-caryophyllene (15.2%), caryophyllene oxide (13.9%), germacrene D (11.6%) and bicyclogermacrene (10.0%). Major components of the oil of T. cyprium were β-pinene (35.4%), α-pinene (10.6%) and spathulenol (8.4%). Major compounds of the oils of T. micropodioides samples, collected from two different locations, were (1) limonene (47.0%), β-pinene (16.0%) and β-caryophyllene (6.9%), (2) δ-cadinene (11.2%), 1-epi-cubenol (7.8%), cubebol (4.7%), cubenol (4.1%), respectively. Main constituents of the essential oil of T. karpasiticum were limonene (43.9%), β-pinene (16.0%), α-bisabolol oxide A (7.8%), β-caryophyllene (5.5%) and α-pinene (4.6%). The section Polium, is considered a complex and the diversity of oil compositions from the species belonging to this section provided additional proof to this consideration.