Primary study on the components and physico chemical as well as biological properties of the essential oil from zingiber montanum growing in Lai Chau, Vietnam

The essential oil of Zingiber montanum (J.Koenig) Link ex A.Dietr. growing wild in the province Lai Chau of Vietnam was obtained by steam distillation and dried with Na2SO4. By GC-MS, 31 components in the essential oil were predicted by comparing their retention times and molecular weights mass spectra with those of the standards. In particular, there were 15 hydrocarbons (37.76% monoterpenes and 11.63% sesquiterpenes) and 16 oxygenated components (16.11% aldehydes, 19.99% alcohols, and 13.27% esters). The density (at 20oC), acid index, and ester index of the essential oil were 0.814 g/ml; 0.651 mgKOH/g, and 0.736 mgKOH/g, respectively. The antioxidant activity was determined by using 1,1-diphenyl-2-picrylhydrazol (DPPH) radical percentage inhibition and it was 48.07± 0.32%. Antimicrobial activity against Salmonella typhi, Bacillus cereus, Staphylococcus aureus and Escherichia coli of the essential oil was identified by agar diffusion method.