RESUMO
Representatives of the Achillea genus are widely used as foods or nutraceuticals. Considering the increasing demand for herbal dietary supplements with health promoting effects, the objective of this research was to evaluate the chemical composition and biological activities of the essential oils obtained from sixteen Achillea species (A. biebersteinii, A. wilhelmsii subsp. wilhelmsii, A. aleppica subsp. zederbaueri, A. vermicularis, A. monocephala, A. nobilis, A. goniocephala, A. sintenisii, A. coarctata, A. kotschyi subsp. kotschyi, A. millefolium subsp. millefolium, A. lycaonica, A. spinulifolia, A. teretifolia, A. setacea, and A. schischkinii). Anticholinesterase, antiurease, antityrosinase enzymes inhibition, antioxidant, antimicrobial, toxic and cytotoxic activities of obtained essential oils were investigated. DPPH activities were found to be very low in all studied samples, while ABTS and CUPRAC antioxidant activities were found to be moderate. In addition, all samples were found to have moderate anticholinesterase and antimicrobial effects. It has been determined that the studied species have low cytotoxicity and high toxicity. Besides, chemical composition of the essential oils were determined by GC/MS and the results were chemometrically analyzed. The chemometric analyses of Achillea species collected from nine different regions were accomplished by principal component analysis (PCA) and hierarchical cluster analysis (HCA) techniques. According to the PCA analysis, A. nobilis subsp. neilreichii was found to be different from all studied species in terms of essential oil composition. The major components found in these species were piperitone, camphor, α-terpinene, eucalyptol, artemisia ketone, endo-borneol, ß-eudesmol and verbenol. The fact that camphor was toxic and found in majority of the studied species stands out as a remarkable result.