Antimicrobial efficacy and chemical constituents of pseudo-stem essential oils from <i>Zingiber castaneum</i>

Abstract

In this paper, chemical constituents and antimicrobial activity of essential oil from the pseudo-stem of <em>Zingiber castaneum </em>Škorničk. & Q.B. (Zingiberaceae) Nguyễn growing in Vietnam havw been reported. Essential oils were obtained by hydrodistillation using the Clevenger-type apparatus. Chemical components of the essential oil were analyzed by gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC/MS). The minimum inhibitory concentrations (MIC) were evaluated by the method of microdilution broth susceptibility assay. The main constituents of the oil were bicyclo­germacrene (<strong>28</strong>, 15.8%), <em>cis</em>-β-elemene (<strong>18</strong>, 9.8%) and germacrene D (<strong>26</strong>, 9.2%). The pseudo-stem oil of <em>Z. castaneum </em>displayed antimicrobial activity against <em>Pseudomonas aeruginosa </em>(ATCC 25923), <em>Aspergillus niger </em>(ATCC 9763) and <em>Fusarium oxysporum </em>(ATCC 48112) with MIC values of 12.5 ± 0.57 μg/mL, 50 ± 1.00 μg/mL and 50 ± 0.50 μg/mL, respectively. The results indicate the potential of <em>Z. castaneum </em>essential oil as a source of antimicrobial agent.