ANTIBACTERIAL EFFECTS OF NATURAL VOLATILE ESSENTIAL OIL FROMZANTHOXYLUM PIPERITUM A.P. DC. AGAINST FOODBORNE PATHOGENS

Abstract

The essential oil (10 µg/well) of Zanthoxylum piperitum exerted inhibitory activity on the growth of all foodborne pathogens by the agar well diffusion susceptibility assays. Limonene and α-pinene exhibited the potent antibacterial activity on all foodborne pathogens tested, and specially α-pinene among test materials had the strongest antibacterial activity. The minimum inhibitory concentration value of Z. piperitum essential oil was investigated to be 1.25 µg/mL, similar for all test foodborne pathogens, and minimum bactericidal concentration (MBC) values (2.5 µg/mL) of Z. piperitum essential oil indicated potent activity for killing Bacillus cereus and Bacillus subtilis. The MBCs were found to be lower on Listeria monocytogenes, Staphylococcus aureus, Aeromonas hydrophila and Vibrio parahaemolyticus (MBC = 10 µg/mL) than that of Salmonella choleraesuis, Salmonella enterica and Vibrio vulnificus (MBC = 20 µg/mL). At 4-h exposure to Z. piperitum essential oil, all bacteria were inhibited to over 60% for the growth of cells, and also after 8-h exposure, showed the inhibition of growth to almost complete. PRACTICAL APPLICATIONS Currently because of the rising concern on chemical preservatives, the food industry is reflecting the consumer opinions for safer additives and focusing on natural safe preservatives. Some plant materials are used as natural antimicrobials in food systems to prevent the growth of foodborne bacteria and molds, resulting in the extension of the shelf life of processed foods. This study has shown that Z. piperitum essential oil can be used to control the growth of several foodborne pathogens. It is anticipated that Z. piperitum essential oils and its components may have greater potential as food preservatives.