Determination of chemical components in the rhizomes of Hedychium Coronarium

Abstract

Hedychiumcoronariumor locally known as white ginger lily belongs to Zingiberaceae family. Hydrodistillation of the fresh rhizomes yielded 0.02% of the essential oil. The composition of the essential oil was analyzed both by gas chromatography and gas chromatography-mass spectroscopy. Eleven compounds were identified representing 79.78% of the whole compositions. 1,8-Cineole (39.03%) is the major component in the essential oil. Soxhlet extraction of the dried rhizomes of H. coronarium with chloroform as solvent yielded a crude extract 4.42%. Purification of the extract took place using column chromatography and preparative thin layer chromatography had afforded two diterpenes. Their structures have been identified using spectroscopic methods as two isomers of coronarin D (1.02%) and 14,15-dihydroxylabda-8(17),12-diene-15,16-olide (coronarin G) (0.1%). Antioxidant property was screened using DPPH radical scavenging assay and has been carried out on the chloroform crude extract, essential oil and two pure compounds. The results revealed that the crude extract gave moderate antioxidant property with IC₅₀ 275.05 µg/mL. The antibacterial assay was conducted on chloroform crude extract, essential oil and coronarin D. Coronarin D was found to show moderate antibacterial property towards Gram positive bacteria Bacillus subtilis (BS) ATCC 6633 at a concentration of 450 ppm.