Diversity analysis of Kaempferia galanga L. germplasm from South India using DIVA-GIS approach

Abstract

Kaempferia galanga L. (Zingiberaceae) is an important indigenous medicinal plant of India. Plant rhizomes are used in the preparation of Ayurvedic drugs, perfumes and cosmetics. K. galanga germplasm collected from southern states of India were evaluated for essential oil content and oil composition. The volatile composition of essential oil of Kaempferia galanga L. was investigated by gas chromatography (GC) and Gas chromatography–mass spectrometry (GC/MS). Results showed wide variations in essential oil content of K. galanga rhizomes ranging from 0.83 to 2.19% on dry weight basis. Thirty-eight compounds were identified in the Kaempferia oil. The oil composition was dominated by two esters viz; ethyl-trans-p-methoxy cinnamate (28.35–69.96%) and trans-ethyl cinnamate (11.48–26.56%). Other prominent chemical constituents were δ-3-carene (0.13–6.46%), 1,8-cineole (0.19–5.17%), borneol (0.96–2.40%) and pentadecane (6.04–16.53%). DIVA-GIS analysis of K. galanga germplasm for chemical components indicated that diverse accessions can be obtained from Central Kerala, while South Eastern parts of Kerala possessed least diversity indices. Superior accessions were identified based on high content of ethyl-trans-p-methoxy cinnamate (IC373589, IC087831, IC373591) and trans-ethyl cinnamate (IC087826, IC210748, IC087832). Ethyl-trans-p-methoxy cinnamate and trans-ethyl cinnamate are found to be the most important constituents present in the essential oil isolated from all the accessions of K. galanga which are reported to be responsible for most of the pharmacological properties of the plant. Hence, these promising accessions of K. galanga can be exploited for large-scale cultivation of this plant for obtaining higher yields of pharmacologically important constituents.