Screening of two Achillea (Asteraceae) species from Turkey, Achillea coarctata Poir. and Achillea setacea Waldst. & Kit. for volatiles and fatty acids compositions, and antimicrobial activity

The main aim of this study is antimicrobial screening of the n-hexane, ethyl acetate and aqueous extracts obtained from aerial parts of Achillea setacea Waldst. & Kit. and Achillea coarctata Poir. against the bacterial strains Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 14028 and the yeast Candida albicans ATCC 6633 by the microdilution method. In addition, the effect of the aqueous extract of A. coarctata combined with fluconazole againts C. albicans ATCC 6633, C. parapsilosis ATCC 22019, C. tropicalis ATCC 750 and C. glabrata ATCC 90030 was tested with the checkerboard method. The chemical components of the volatiles and fatty acid methyl esters were identified using the Gas Chromatography (GC) and Gas Chromatography/Mass Spectrometry (GC/MS) techniques. The main components of the volatile oil were found to be 1,8-cineole (16.1%) and β-pinene (14.5%) for A. setacea and camphor (35.4%) and borneol (12.9%) for A. coarctata. The ethyl acetate extracts of A. setacea (MIC=156.25 µg/mL) and A. coarctata (MIC=312.5 µg/mL) were found more active against the tested Candida Berkh. species. The combination of aqueous extract of A. coarctata with fluconazole showed additive effect for the tested Candida species with FIC values within the range of 0.53-0.625 µg/mL.