Chemical Compositions of the Volatile Oils and Antibacterial Screening of Solvent Extract from Downy Lavender

Abstract

The discovery of a new species exhibiting more effective antibacterial properties is necessary because of the demand on <i>Lavandula</i> species, which continues to increase in a variety of industries. <i>Lavandula pubescens</i> might be a good alternative, as it exhibits strong antibacterial activity. In this study, the chemical composition of the essential oils from different organs (flowers, leaves, stems, and roots) of <i>L. pubescens</i> was identified using gas chromatography-mass spectrometry. Furthermore, the antimicrobial activities of different solvent extracts (methanol, ethanol, diethyl ether, hexane, and ethyl acetate) and different organ (flower, leaf, stem, and root) extracts of <i>L. pubescens</i> were evaluated. Only the ethyl acetate extracts of <i>L. pubescens</i> exhibited antibacterial activity against all bacterial strains tested, including <i>Staphylococcus haemolyticus</i>, <i>Escherichia coli</i> (KF 918342), <i>Aeromonas hydrophila</i> (KCTC 12487), <i>E. coli</i> (ATCC 35150), <i>Cronobacter sakazakii</i> (ATCC 29544), and <i>Aeromonas salmonicida</i> (KACC 15136). In particular, the extracts exhibited significant activity against <i>S. haemolyticus.</i> Ethyl acetate extract of the leaf exhibited the best activity against all bacterial strains. This study provides valuable information on the chemical compositions in essential oils and antimicrobial properties of <i>L. pubescens</i>.