Chemical Composition and Antimicrobial Activity of the Essential Oils of Nepeta alpina Growing Wild in Iran

The increase in agricultural production can be possible with the discovery and utilization of chemical compounds for plant disease control. However, indiscriminate use of chemical compounds against microorganisms causes many negative side effects on environment and mammalian health. The hydro distilled volatile oil from aerial parts of Nepeta alpina was analyzed by GC-MS. Seven compounds (95.88 %) were identified of the total oil. germacrene D (24.95 %), bicyclogermacrene (17.67 %) spathulenol (14.80 %) and caryophyllene oxide (12.94 %) were the main components. The antimicrobial activity of the aerial part essential oils of N. alpina is screened against Gram-positive and Gram-negative bacteria, and fungi. The best antibacterial activity was observed against Listeria monocytogenes with ZI (11.0 +/- 0.5) mm and MIC value of 32 mu g/ml.