Characterization of the Antibacterial Activity and the Chemical Components of the Volatile Oil of the Leaves of <em>Rubus parvifolius</em> L.

Abstract

<em>Rubus parvifolius</em> L. (Rp) is a medicinal herb that possesses antibacterial activity. In this study, we extracted the volatile oil from the leaves of Rp to assess its antibacterial activity and analyze its chemical composition. A uniform distribution design was used to optimize the extraction procedure, which yielded 0.36% (<em>w</em>/<em>w</em>) of light yellowish oil from the water extract of Rp leaves. We found that the extracted oil effectively inhibited the growth of a wide range of Gram positive and negative bacteria, including <em>Staphylococcus aureus</em>, <em>Staphylococcus epidermidis</em>, <em>Enterococcus faecalis</em>, <em>Escherichia coli</em>, <em>Pseudomonas aeruginosa</em>, <em>Acinetobacter baumanii</em>, <em>Bacillus cloacae</em>, and <em>Klebsiella pneumoniae</em>. We further analyzed the components contained in the hydro-distillated Rp volatile oil by gas chromatography-mass spectroscopy. Twenty nine compounds were identified, including 4-hydroxy-3-methoxystyrene (66%), 3,7,11,15-tetramethyl-2-hexadecen-1-ol (10%) and 4-<em>tert</em>-butylbenzoic acid (2%). Our results suggest that one or multiple constituents contained in Rp volatile oil may account for its antibacterial activity.

Keywords

• &lt;em&gt;Rubus parvifolius&lt;/em&gt; L.
• volatile oil
• 4-hydroxy-3-methoxystyrene
• antibacterial activity