The essential oil quantity and quality as well as antioxidant capacity of Achillea millefolium at different phenological stages including vegetative, flowering and fruit set are reported. The essential oils content (% v/w) of air dried aerial parts was depended on the plant growth stage and was in the order of: vegetative (0.17%), flowering (0.24%) and fruit set (0.14%). The essential oils analysis by GC-FID and GC–MS allowed the identification of 28 volatile constituents, accounting for 92.89-97.28% of the total oil composition. The major constituent at all samples was 1,8-cineole (21.28-34.51%) as a oxygenated monoterpene compound; followed by camphor (7.27-14.07%), chamazulene (4.18-11.34%) and α-eudesmol (2.09-9.63%). Results showed that the essential oils constituents of A. millefolium were varied regards to amount of monoterpene and sesquiterpenes at different phenological stages. A considerable decrease and increase was observed respectively in monoterpene and sesquiterpene contents of essential oils during growth season. The total phenol content and antioxidant activity of A. millefolium extract gradually decreased during plant growth period; however the total flavonoids content did not show great changes at different growth stages. According to obtained results, flowering stage is suggested as the the best stage for production of A. millefolium with the optimal essential oil quantity and quality as well as antioxidant capacity in the extract.

Keywords