Chemical composition and antimicrobial activity of essential oils from Centaurea appendicigera and Centaurea helenioides

The chemical components and antimicrobial activity of the essential oils from Centaurea appendicigera C. Koch and Centaurea helenioides Boiss, two different endemic members of the genus Centaurea L. (Asteraceae), were studied. The essential oils of air-dried C. appendicigera and C. helenioides were obtained by hydrodistillation in a Clevenger-type apparatus and analyzed by GC-MS. Forty-five and fifty-one components were identified in the essential oils of C. appendicigera and C. helenioides, respectively, and the main components of these taxa were found to be β-caryophyllene (17.5%) from C. appendicigera and caryophyllene oxide (18.2%) from C. helenioides. The antimicrobial activity of the isolated essential oil of the plants was also investigated, and demonstrated moderate antibacterial activity against Gram-positive, Gram-negative bacteria, and yeast-like fungi.