Navadha Joshi et al / Int. J. of Res. in Pharmacology and Pharmacotherapeutics Vol-3(1)2014 [68-71] www.ijrpp.com ~ 68~ ISSN Print: 2278 – 2648 IJRPP |Vol 3 | Issue 1 | Jan – Mar -2014 ISSN Online: 2278-2656 Journal Home page: www.ijrpp.com Research article Open Access GC-MS Analysis and antimicrobial activity of essential oil of Nepeta coerulescens Navadha Joshi* 1 , G.C.Sah 2 1 Department of Chemistry, S. S.J. campus, Kumaon University, Almora-263601, Uttrakhand, India. 2 Department of Chemistry, S. S.J. campus, Kumaon University, Almora-263601, Uttrakhand, India. *Corresponding author: Navadha Joshi. Email address : joshinavadha@gmail.com ABSTRACT The chemical composition of the essential oil obtained from the leaves of Nepeta coerulescens collected from the Zanskar sub district of Kashmir, was analyzed by GC-MS. The major constituent terpene hydrocarbon was found out to be caryophyllene oxide (25.146%). The antimicrobial activity of essential oil of N.coerulescens was tested against five bacteria and two fungi, by disc diffusion method. Results showed that the oil exhibited mild antibacterial activity and good antifungal activity. Keywords: Nepeta coerulescens, Antibacterial, Antifungal, Caryophyllene oxide, Lamiaceae, Essential oil. INTRODUCTION Nepeta L. with approximately 300 species, most of which are herbaceous perennials, is one of the largest genera in the family Lamiaceae, subfamily Nepetoideae, tribe Mentheae. Its species are distributed throughout Southwest and Central Asia, Europe, North Africa, North and Central America, Japan, Korea, China, and the Canary Islands [1-3]. Most of the species are found in South-western Asia, especially Iran, Central Asia and Trans-Caucasia. Nepeta is the second largest genus of the Indian labiates, with 41 species in all, 37 of which occur in the Western Himalaya [4]. N. campestris and N. eriostachya were observed to be endemic to India [5]. In the Kashmir Himalaya, about 27 species have been reported [6], but some of them are now considered as synonyms to other species. For the first time the exact number of species of Nepeta was recorded [7] through extensive survey of Kashmir Himalaya and consultation of literature as well as specimens preserved in different herbaria. N. elata, N. royleana, N. pamirensis and N. vakanica recorded previously from the study area are actually the synonyms of N. laevigata, N.salviaefolia, N.kokanica and N.floccosa respectively. International Journal of Research in Pharmacology & Pharmacotherapeutics