Composition and Antioxidant Activity of the Essential Oil from Achillea moschata Wulfen Growing in Valchiavenna and Valmalenco (Italian Central Alps)

Achillea moschata Wulfen (Asteraceae) is an endemic species growing on the Alps and traditionally used in several medicinal remedies. For its aromatic properties, it is also collected for food purposes. Chemical content and biological activity of A. moschata oil are not extensively studied. We investigated whether the different lithological and geomorphological features of two alpine areas including Vallone dello Scerscen and Valle dei Ratti, located in the Sondrio Province (Northern Italy), can influence the essential oil (EO) composition and the related antioxidant activity of the respective A. moschata populations. The essential oils obtained by steam distillation from the dried aerial parts were investigated by GC/FID and GC/MS. Several compounds were identified belonging to different chemical classes, including monoterpenes and sesquiterpenes as the most abundant constituents, together with ketones, alcohols, phenols, acids and esters. A variation in the quantitative composition of several constituents was recorded in the two oils. The main constituents were camphor (23.4-34.2%), 1,8-cineole (9.8-16.4%), trans-tujone (3.6-13.4%), sesquicineole (3.5-5.8%), borneol (1.1-4.8%), -caryophyllene (2.7-4.4%) and myrcene (1.3-4.2%). Their antioxidant activity was measured in vitro by the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⋅+) and 2,2-diphenyl-picryl hydrazyl (DPPH⋅) stable radical assays. The essential oils showed similar and significant scavenger effects, possibly due to the synergistic action of all components including compounds present in small quantities.