Biological activities of the essential oils of some mint (Mentha L.) species of Turkey

Chemical compositions, antimicrobial, antioxidant and enzyme inhibitory activities of the essential oils of the following mint species growing in Marmara and Black Sea regions of Turkey have been investigated: Mentha longifolia L. Hudson subsp. typhoides, M. suaveolens Ehrh, M. spicata L. subsp. spicata, M. spicata L. subsp. tomentosa, M. pulegium L., M. x villosa-nervata Opiz.Antioxidant activity was tested using four different test systems namely ß -carotene, DPPH?, ABTS?+ and reduction power. Mint oils showed activity only against the ABTS?+ radical cation.Antimicrobial activity (antibacterial and anticandidal) was tested agains some gram-negative and gram-positive bacteria and some Candida species using microdilution method. Mint oils showed better activity against Candida species as compared to bacteria.Enzyme inhibitory activities against acetylcholine esterase (AChE) and butyrylcholine esterase (BuChE) were determined. No activity was observed against AChE, however, the oil of M. spicata L. subsp. spicata showed stronger activity than the control Galanthamine against BChE.Keywords: Antioxidant activity, DPPH?, ABTS?+, ß-carotene/linoleic acid, anticandidal activity, acetylcholine esterase (AChE) inhibitory activity, butyrylcholine esterase (BuChE) activity