en Nutrition Nutrition پژوهشي Research <p><strong>Background and Objectives:</strong><em> Vibrio parahaemolyticus</em> is the causative agent of gastroenteritis due to consumption of contaminated seafood. The aim of the present study was to determine the chemical composition of Essential Oils (EOs) of five plants (<em>Artemisia absinthium, Zataria multiflora Boiss., Pulicaria gnaphalodes, Trachyspermum ammi</em> and <em>Cuminum cyminum</em>) and to evaluate their antimicrobial activity against pathogenic and non-pathogenic <em>V. parahaemolyticus</em>.</p> <p><strong>Materials and Methods: </strong>The EOs were analyzed by gas chromatography mass spectrometry. The detection of inhibitory effect of the EOs on the tested bacteria was carried out by agar disc-diffusion method and then MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal Concentration) of the EOs against both bacteria were determined.</p> <p><strong>Results: </strong>The analysis of the components of the EOs by gas chromatography mass spectrometry allowed the identification of 76 compounds. Of the five tested EOs, four oils exhibited an antimicrobial effect against both strains of <em>V. parahaemolyticus</em>. In all EOs tested, Pathogenic <em>V. parahaemolyticus</em> showed more sensitivity than non-pathogenic <em>V. parahaemolyticus</em>. The strongest EO against pathogenic <em>V. parahaemolyticus</em> were <em>T. ammi</em> with 63.42% thymol and<em> C. cyminum</em> with 29.02% cuminaldehyde and 20.70% &alpha;-terpinene-7-al, equally (31 mm inhibition zone). Non-pathogenic <em>V. parahaemolyticus</em> showed the most sensitivity against <em>Z. multiflora</em> Boiss. EO with 73.64% carvacrol (27 mm inhibition zone and the lowest MIC (0.025%) and MBC (0.05%)). Despite the large amount of thujone,<em> A. absinthium</em> EO in this study did not show antibacterial activity in disk diffusion assay, MIC or MBC values.</p> <p><strong>Conclusions: </strong>The results of this study suggest that<em> Z. multiflora</em> Boiss. and<em> T. ammi</em> have strong antimicrobial activity against both pathogenic and non-pathogenic <em>V. parahaemolyticus.</em></p> <p></p> Chemical Composition, Antimicrobial Effect, Essential Oils, Vibrio parahaemolyticus 43 52 http://nfsr.sbmu.ac.ir/browse.php?a_code=A-10-533-1&slc_lang=en&sid=1 Razieh Partovi r.partovi@ausmt.ac.ir 10031947532846002013 10031947532846002013 Yes Department of Food Hygiene, Faculty of Veterinary Medicine, Amol University of Special Modern Technologies, Amol, Iran Ali Khanjari khanjari@ausmt.ac.ir 10031947532846002014 10031947532846002014 No Department of Food Hygiene, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran Sepideh Abbaszadeh Abbaszadehs@bmsu.ac.ir 10031947532846002015 10031947532846002015 No Department of Nutrition and Food Hygiene, Faculty of Health Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran Aghil Sharifzadeh asharifzadeh@ut.ac.ir 10031947532846002016 10031947532846002016 No Mycology Research Center, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran