Volatile Oil Composition and Antiplatelet Activity of Jordanian Achillea biebersteinii Collected at Different Growth Stages

Achillea biebersteinii Afan. (Asteraceae) is used as a traditional medicine for healing wounds and in the treatment of abdominal pain and stomach ache. Fresh and air dried flowering parts of A. biebersteinii at different growth stages were subjected to hydro-distillation and the different essential oils obtained were analyzed by GC-MS technique. Monoterpenoids dominated the different flowering stages of both, fresh and air dried flowering parts. The fresh pre-flowering stage was dominated by monoterpene hydrocarbons (56.62 %) with alpha-terpinene as the major component (51.67 %). Oxygenated monoterpenes were detected as the principal constituents during both, the fresh flowering and fresh post-flowering stages (55.61 %, 56.45 %, respectively). The major representatives of this class included ascaridol (38.84 %) and iso-ascaridol (25.39 %). Oxygenated monoterpenes dominated all flowering stages of the air-dried blooms and ascaridol was the main volatile compound in these oils (28.20 %, 27.03 % and 44.39 %, respectively). The oil of the dried mature flowering blooms of A. biebersteinii exhibited dose-dependent inhibition of the platelet aggregation caused by ADP and collagen.