Two flavanones from finger-root (Curcuma rotunda) and its antibacterial activities

Abstract

Finger-root (Curcuma rotunda) belongs to Zingiberaceae family, commonly used as a medicinal plant but has not been widely reported for its secondary metabolites and bioactivities. This study aims to isolate and characterize secondary metabolites contained in the semi-polar extract of C. rotunda rhizomes and evaluate its antibacterial activities. Simplicia of C. rotunda rhizomes was macerated using acetone, fractionated using vacuum liquid chromatography followed by radial chromatography, and purified using preparative thin layer chromatography to yield two isolated compounds. Based on FTIR and NMR spectroscopic data, two isolated compounds were elucidated as flavanone derivatives i.e. pinocembrin (1) and pinostrobin (2). Nevertheless, both of two isolated compounds did not show antibacterial activities toward Staphylococcus aureus and Pseudomonas sp.