¹Department of Biology, Borujerd Branch, Islamic Azad University, Borujerd, Iran
²Research Division of Natural Resources, Lorestan Agricultural and Natural Resources Research and Education Center, AREEO, Khorramabad, Iran
³Razi Herbal Medicines Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran DOI : 10.12991/jrp.2019.141 In this study, chemical composition, antioxidant and antimicrobial activity of the essential oil of Nepeta cataria L., a native plant that grows in Lorestan region of Iran, were studied. Chemical constituents of the essential oil were identified by means of gas chromatography/mass spectrometry (GC/MS) and the relative content of each constituent was determined by area normalization. Disc diffusion and broth microdilution assays were used for in vitro antimicrobial screening. Antioxidant activity was employed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging. The predominant bioactive ingredients with high percentage in N. Cataria essential oil was 4a-α, 7-α, 7a-β-Nepetalactone (53.87%). The essential oil’s IC₅₀ value of 80.62 μg / mL in the DPPH assay, could be regarded as its strong antioxidant potential. The antibacterial activities of the essential oil were screened and compared against dozen important human pathogens. The essential oil showed good antibacterial activity, especially on Salmonella spp.. The biggest diameters of inhibition zones (29 mm) was recorded for Salmonella typhi and Salmonella paratyphi A showed the lowest MIC (160 μg / mL). Keywords : Antimicrobial; antioxidant, Nepeta cataria L.; essential oil