Faculty of Veterinary Medicine, Urmia University Veterinary Research Forum 2008-8140 7 1 2016 03 01 Inhibitory effect of Zataria multiflora Boiss. essential oil, alone and in combination with monolaurin, on Listeria monocytogenes 7 11 19005 EN Mojtaba Raeisi Department of Public Health, Faculty of Health, Golestan University of Medical Sciences, Gorgan, Iran Cereal Health Research Center, Golestan University of Medical Sciences, Gorgan, Iran 0000-0003-1787-6319 Hossein Tajik Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran Seyed Mehdi Razavi Rohani Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran Bektas Tepe Department of Molecular Biology and Genetics, Faculty of Science and Literature, Kilis 7 Aralik University, Kilis, Turkey Hossein Kiani Bioprocessing and Biodetection Laboratory, Department of Food Science, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran Rahem Khoshbakht Department of Food Hygiene and Public Health, Faculty of Veterinary Medicine, Amol University of Special Modern Technologies, Amol, Iran 0000-0002-9812-7696 Hesamaddin Shirzad Aski Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran Hamed Tadrisi Graduated of Veterinary Medicine, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran Journal Article 2016 03 14 <em>Listeria monocytogenes</em> is one of the major causes of infections in developing countries. In this study, chemical composition and anti-listerial effect of the essential oil of <em>Zataria multiflora</em> Boiss. alone and in combination with monolaurin were evaluated at different pH values (5, 6, and 7) and temperatures (5 ˚C and 30 ˚C). Chemical composition of <em>Zataria multiflora</em> Boiss. essential oil was evaluated by gas chromatography-mass spectrometry (GC-MS) analysis. Minimum inhibitory concentration (MIC) of the essential oil and monolaurin were determined using microbroth dilution method and the interactions of essential oil and monolaurinwere determined by the evaluation of fractional inhibitory concentrations (FIC) index.Carvacrol (63.20%) and thymol (15.10%) were found as the main components of the essential oil. The MIC values of the oil and monolaurin at pH 7 and 30 ˚C were measured as 312.50 µg mL^-1 and 125.00 µg mL^-1, respectively. Combination of monolaurin and <em>Z. multiflora</em> essential oil were found to act synergistically (FIC index < 0.5) against <em>L. monocytogenes</em> under different pH and temperature conditions. Decrease in the pH and temperature values have increased the anti-listerial activity of monolaurin and the essential oil. The lowest MIC value of monolaurin and essential oil was observed at pH 5 and 5 ˚C. According to our results, the oil alone or in combination with monolaurin at low pH and temperature conditions showed a promising inhibitory effect on <em>L. monocytogenes</em>. https://vrf.iranjournals.ir/article_19005_b164b8c8c0edca0bd7748490013cc79b.pdf