Differentiation of Achillea millefolium, A. crithmifolia, and A. nobilis through Analysis of Volatile Constituents using HS-SPME-GC/MS and Chemometric Techniques

Achillea millefolium, A. crithmifolia and A. nobilis are distinct species that share morphological similarities, making their differentiation challenging. This study utilized gas chromatography-mass spectrometry (GC/MS) combined with headspace-solid phase microextraction (HS-SPME) to analyze the volatile components of these species and employed chemometric methods for species differentiation. A total of 109 volatile compounds from the three studied species were identified. Of these compounds, 71 were identified in A. millefolium, 75 in A. crithmifolia, and 58 in A. nobilis. The primary volatile compounds of A. millefolium were germacrene D, 1,8-cineole, sabinene, and β-pinene; in A. crithmifolia, the main compounds were caryophyllene, 1,8-cineole, camphor, ascaridole, and ο-cymene, while in the essential oil of A. nobilis, camphor, lavandulyl acetate, camphene, and isobornyl acetate were determined as the main volatile compounds. The study demonstrated that the HS-SPME-GC/MS techniques, combined with chemometric methods such as discriminant analysis (DA) and principal component analysis (PCA), effectively distinguished the samples of A. millefolium, A. crithmifolia, and A. nobilis based on the differences in the chemical composition of their essential oils.