Sesquiterpene Rich Essential Oil from<i>Plectranthus rugosus</i>Wall

Abstract

Abstract The essential oil obtained by steam distillation from the leaves of Plectranthus rugosus Wall. syn. Rabdosia rugosa Wall., was analyzed by GC and GC-MS. The GC and GC-MS analysis showed the presence of 30 constituents, of which twenty-five constituents were identified, constituting 87.9% of the total oil. The major constituents being sesquiterpene hydrocarbons viz. ß-caryophyllene (38.4%) and germacrene D (23.8%) besides spathulenol (3.2%) and Ot-cadinol (2.2%). p-Cymene (3.6%), y-terpinene (2.8%) and limonene (2.7%) were among the monoterpenes hydrocarbons present in significant quantity.