fa Food Safety and Hygiene Food Safety and Hygiene پژوهشي Original Article <div style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:times new roman;"><strong>Background:</strong> Active antimicrobial packaging is a novel method for increasing the safety and shelf life of food products. The present study aimed to investigate the inhibitory effects of chitosan coating nano-emulsion incorporated with <em>Zataria multiflora</em> and <em>Bunium persicum</em> essential oils at the concentrations of 0.5% and 1%, respectively on <em>E. coli </em>O₁₅₇:H₇ in vacuum-packed fish samples during 12 days of refrigeration.<br> <strong>Methods: </strong>The samples were divided into various groups, including control (no coating), 2% chitosan, 2% chitosan nano-emulsion, and chitosan coating nano-emulsion containing <em>Zataria multiflora</em> and <em>Bunium persicum</em> essential oils at the concentrations of 0.5% and 1%, respectively. The samples were vacuum-packed and stored at refrigeration temperature, and bacterial counting was performed on days zero, one, two, four, six, eight, and 12.<br> <strong>Results:</strong> The mean bacterial count had a significant difference between the study groups during 12 days of storage (<em>P</em> < 0.001). The most significant inhibitory effect on the growth of <em>E. coli</em> O₁₅₇:H₇ was observed with nano-emulsion of chitosan containing 1% of <em>Bunium persicum.</em><br> <strong>Conclusion:</strong> According to the results, using the nano-emulsion of chitosan coating with essential oils could effectively decrease the growth of <em>E. coli</em> O₁₅₇:H₇ in food products, especially fish.in food especially fish.</span></span></div> <br> &nbsp; Chitosan, Nano-emulsion, Zataria Muitiflora, Bunium persicum, E.coli O157:H7 21 25 http://jhehp.zums.ac.ir/browse.php?a_code=A-10-144-2&slc_lang=fa&sid=1 Fatemeh Raji a.nasim_93@yahoo.com 10031947532846009673 10031947532846009673 No Department of Food Hygiene and Aquatics, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Iran. Saeid Khanzadi Khanzadi@um.ac.ir 10031947532846009674 10031947532846009674 Yes Department of Food Hygiene and Aquatics, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Iran. Mohammad Hashemi Mo_hashemi@hotmail.com 10031947532846009675 10031947532846009675 No Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Mohammad Azizzadeh m-azizzadeh@um.ac.ir 10031947532846009676 10031947532846009676 No Department of Clinical Science, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Iran.