Antibacterial Activity of Essential Oils from Zanthoxylum piperitum A.P. DC. and Zanthoxylum schinifolium

This study was carried out to investigate the potential use of Zanthoxylum schinifolium and Zanthoxylum piperitum A.P. DC. as a source of antimicrobial agents against food borne pathogens. Essential oils of Z. schinifolium and Z. piperitum A.P. DC. were collected by steam distillation and analyzed by GC-MS. The antimicrobial activity of the essential oils was examined using the agar diffusion and micro-dilution assays. The effectiveness of Z. schinifolium essential oil was greater against Bacillus cereus, Staphylococcus aureus, and Vibrio parahaemolyticus than other pathogens, and the minimal inhibitory concentration (MIC) values were 1.25, 2.5, and 1.25, 2.5, and $1.25\;{\mu}g/mL$, respectively. Z. piperitum A.P. DC. essential oil was the most effective against all pathogens tested except for Escherichia coli O157:H7, and the MIC values against B. cereus, Salmonella choleraesuis, and V. parahaemolyticus were 1.25, 2.5, and $1.25\;{\mu}g/mL$, respectively. Limonene, the major component of Z. piperitum A.P. DC. essential oils, had the highest inhibitory activity toward V. parahaemolyticus with a MIC value of $0.15\;{\mu}g/mL$. Meanwhile, citronellal and geranyl acetate, major components of both essential oils, displayed antibacterial activity against only B. cereus with MIC values of 1.25 and $5\;{\mu}g/mL$, respectively. Therefore, these essential oils could be useful as antimicrobial agents against foodborne pathogens.