en فارماکوگنوزی Pharmacognosy پژوهشي Original Research Plant essential oils and natural extracts have been attracted research interest to control bacterial contamination of food products. <em>Staphylococcus aureus </em>and <em>Listeria monocytogenes </em>considered as public health bacterial hazards which survive in various types of food. The aim of the current study was to assess the effects of <em>Mentha spicata</em> essential oil (MSO: 0, 0.1 and 0.2%) alone and in combination with methanolic carrot extract (MCE) (0, 0.25 and 0.5%) against <em>S. aureus</em> and <em>L. monocytogenes</em> in fish soup. Untreated and treated homemade fish soups with different concentrations of MSO and MCE were inoculated with 5 log CFU/ml of <em>S. aureus </em>and <em>L. monocytogenes, </em>and then stored at 4 &plusmn; 1 &ordm;C (refrigerated temperature), 9 &plusmn; 1 &ordm;C (abused temperature) and 25 &plusmn; 1 &ordm;C (room temperature) during 15 days. Based on our findings, carvone (78.76%) and limonene (11.50%) were the major compounds of the MSO. The following sequence inhibition effect on <em>S. aureus </em>and<em> L. monocytogenes </em>was observed in treated soups: MSO 0.2% + MCE 0.5% > MSO 0.2% + MCE 0.25% > MSO 0.2% > MSO 0.1% + MCE 0.5% > MSO 0.1% + MCE 0.25% > MSO 0.1% > MCE 0.5% > MCE 0.25%. The results of the present study demonstrated that antibacterial effects of different concentrations of MSO separately and in combination with MCE were higher at 4 and 9 &ordm;C than 25 &ordm;C (<em>P</em><0.05). &nbsp; Mentha spicata essential oil, Carrot extract, Staphylococcus aureus, Listeria monocytogenes, Fish soup 32 38 http://pbr.mazums.ac.ir/browse.php?a_code=A-10-578-1&slc_lang=en&sid=1 yasser shahbazi یاسر شهبازی yasser.shahbazi@yahoo.com 10031947532846004042 10031947532846004042 No Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Razi University, Kermanshah, Iran دانشکده دامپزشکی دانشگاه رازی nassim shavisi نسیم شاویسی nassim.shavisi@yahoo.com 10031947532846004043 10031947532846004043 Yes Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Razi University, Kermanshah, Iran دانشکده دامپزشکی-دانشگاه رازی