Terpenoid composition of the essential oils of Teucrium royleanum and T. quadrifarium.

Teucrium royleanum Wall ex. Benth. and T. quadrifarium Buch.-Ham., growing wild in the Central Himalayan region of Uttarakhand (India), yielded, on steam distillation, 0.07% and 0.09%, respectively of essential oil. The oil samples were analyzed by GC and GC-MS. By GC, both oil samples showed remarkable similarity with respect to the major peaks. Fifty-seven constituents were identified in both the oils representing 96.0% and 96.6% of the total, respectively. The oils were rich in sesquiterpene hydrocarbons (approximately 76.0%). beta-Caryophyllene (23.6% and 38.3%), germacrene D (28.9% and 9.4%), alpha-humulene (5.7% and 5.9%), linalool (4.8% and 1.5%), and 1-octen-3-ol (8.5% and 0.7%) were common to both oils and were the principal constituents. The genus can be classified into two groups on the basis of the present and previous reports on the essential oil composition and chemical markers.