en سلامت جانبازان يا معلولان Veterans or Handicapped Health پژوهشی اصيل Original Research <div style="text-align: justify;"><strong>Aims:</strong><em> Nigella sativa</em> is recognized as a black seed. It is a grassy plant relating to the Ranunculaceae family. There are various reports regarding this plant&#39;s pharmacological and biological action, like antihypertensive effects, antibacterial, anticancer, antioxidants, antifungal, pain alleviating, anti-inflammatory, antidiabetic, and immune-modulatory effects. This study aimed to compare the anti-microbial activity of aqueous and oil extract of <em>Nigella sativa</em> against selected gram-positive and gram-negative bacteria.<br> <strong>Materials & Methods: </strong><em>Nigella sativa</em> aqueous and oil extracts were gathered via a retail food shop (Al-Hilla) 2018. Gram-positive (<em>Staphylococcus aureus</em>; <em>Streptococcus pneumonia</em>; <em>Streptococcus pyogenes</em>) and Gram-negative (<em>Salmonella typhi; Escherichia coli; Pseudomonas aeroginosa</em>) isolates (obtained via clinical specimens) were utilized.<br> <strong>Findings: </strong>Both <em>Nigella sativa</em> aqueous and oil extracts showed a maximum inhibition zone against <em>E. coli</em> and minimum inhibition against <em>S. pyogenes</em>.<br> <strong>Conclusion:</strong> <em>Nigella sativa</em> acts against gram-positive as well as gram-negative bacterial isolates.</div> Antimicrobial Activity,Nigella sativa,Medicinal Plant,Minimum Inhibitory Concentration, 305 311 http://ijwph.ir/browse.php?a_code=A-10-1868-1&slc_lang=en&sid=1 T. Dhahir Mansour Al Sultani 15300319475328460023915 15300319475328460023915 Yes Department of Microbiology, Al-Esraa University College, Baghdad, Iraq S. Ayad Fakhri 15300319475328460023916 15300319475328460023916 No Department of Pharmacology and Toxicology, Al-Esraa University College, Baghdad, Iraq W.H.N. Al-Zuhairi 15300319475328460023917 15300319475328460023917 No Pharmacy Department, Al-Esraa University College, Baghdad, Iraq