Essential Oils of Two Ginger Plants Newmania orthostachys NS LATIN SMALL LETTER Y WITH ACUTE & Skornick. and N. serpens NS LATIN SMALL LETTER Y WITH ACUTE & Skornick.: Chemical Compositions and Antimicrobial Activity

The current study describes chemical compositions and antimicrobial activity of essential oils from the rhizome of two Vietnamese ginger plants Newmania orthostachys N.S. LATIN SMALL LETTER Y WITH ACUTE & Skornick. and Newmania serpens N.S. LATIN SMALL LETTER Y WITH ACUTE & Skornick. 49 compounds (98.4%) were identified in N. orthostachys rhizome oil, whereas 54 compounds (93.4%) were identified in N. serpens rhizome oil. N. orthostachys rhizome essential oil was dominated by monoterpene hydrocarbons (74.2%), in which beta-pinene (35.7%), alpha-pinene (13.4%), sabinene (8.0%), camphene (6.7%), and limonene (5.1%) were characteristic compounds. Monoterpene hydrocarbons (33.5%) and sesquiterpene hydrocarbons (44.1%) represented N. serpens rhizome essential oil, as well as beta-pinene (18.5%), bicyclogermacrene (12.4%), beta-selinene (8.2%) were the principal compounds. In an antimicrobial assay against three tested Gram-positive bacteria Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, and Bacillus cereus ATCC 14579, both two essential oils showed the minimum inhibitory concentration (MIC) values of 16-64 mu g/mL lower than those of positive control Streptomycin (MIC 128-256 mu g/ml). These two essential oils with the MIC values of 8-16 mu g/mL are also better than the positive control cycloheximide (MIC 32 mu g/mL) against the yeast Candida albicans ATCC 10231.

Automated summary

The current study investigates the chemical compositions and antimicrobial activity of essential oils from the rhizome of two Vietnamese ginger plants. The results show that these essential oils have significant inhibitory effects on various bacteria and fungi.