ANALYSIS OF ESSENTIAL OIL CONSTITUENTS OF THREE ANNONA SPECIES GROWING IN KERALA, INDIA

Abstract

The volatile chemical composition of leaf essential oils of three Annona species (Annona cherimola, Annona muricata and Annona squamosa) from the different regions of Kerala, South Indian was determined using gas chromatography-mass spectrometry analysis. A total of 41 constituents belonging to monoterpenoids, sesquiterpenoids and diterpenoids were identified. Monoterpenes and sesquiterpenoids were the major class of volatile compounds in most of the Annona species examined. The study led to the identification of major compounds as germacrene D (23.5%), bicyclogermacrene (14.6%) and β-caryophyllene (11.7%) in A. cherimola, α-pinene (13.3%), β-caryophyllene (11.2%) and β-pinene (10.1%) in A. muricata, and β-caryophyllene (11.9%) and α-pinene (8.2%) in A. squamosa respectively. The examined essential oils showed that β-caryophyllene is the common constituent identified in all the three species and other constituents are more specific for each species under study. Present investigation reports, a comparison of essential oil compositions of three Annona species from Kerala. Results of this study prove that essential oils examined have considerable dissimilarity in chemical composition with previously reported leaf essential oil compositions from other regions. A chemotaxonomic analysis of these essential oils based on the distribution of compounds has revealed an efficient method to differentiate Annona species unambiguously.