Chemical components and antimicrobial properties of essential oil distilled from Siliquamomum oreodoxa N.S. Lý & Škornick (Zingiberaceae) rhizomes.

Siliquamomum oreodoxa N.S. Lý & Škorničk is a species of the family Zingiberaceae and is currently only found in Vietnam. Information on the chemical components and antimicrobial activity of S. oreodoxa essential oil has not been reported in the literature. In this work, the potentiality of the essential oil of S. oreodoxa rhizomes against bacteria and fungi were investigated using antimicrobial bioassays. The chemical components of the plant essential oil were also determined by Gas Chromatography-Mass Spectrometry (GC-MS) analysis. A total of forty bioactive compounds represented 89.5% of the oil, the major components of which were β-pinene (31.25%), α-pinene (26.01%), 1,8-cineol (21.35%), α-limonene (4.66%), and γ-terpinene (4.39%). In the antibacterial test, the essential oil showed inhibitory activity against Enterococcus faecalis (MIC = 16 μg/mL, IC50 = 5.34 μg/mL), Pseudomonas aeruginosa (MIC = 64 μg/mL, IC50 = 20.23 μg/mL), and Salmonella enterica (IC50 = 9.24 μg/mL), Candida albicans (IC50 = 9.27 μg/mL), Bacillus cereus (IC50 = 9.45 μg/mL), E. coli (IC50 = 9.76 μg/mL), Staphylococcus aureus (IC50 = 12.45 μg/mL) at similar MIC value ≈ 32 μg/mL. These results encourage further experiments on biological effects and validation for the extract composition of other parts of S. oreodoxa, especially the essential oil compound, for functional food and drug development efforts. [ABSTRACT FROM AUTHOR]