en Related Fields Related Fields مقاله کامل Full Length/Original Article <strong>Background:</strong> The majority of studies on soil <em>Aspergillus</em> concern the isolation and characterization of the antimicrobial compounds produced by this organism. Our previous studies indicated an isolated <em>Aspergillus</em> strain soil to be of interest, and this subject is further investigated here. <strong>Method: </strong>&nbsp;Soil samples of various locations in Iran were collected. Extract from <em>Aspergillus </em>sp. culture was obtained using ethyl acetate fractionation. Antimicrobial activity testing was performed using broth microdilution assay against <em>Escherichia coli</em>, <em>Candida albicans</em>, and <em>Staphylococcus aureus</em> microorganisms. One metabolite PA3-d10 was isolated from these active extracts and identified using thin layer chromatography, preparative thin-layer chromatography, HPLC, ¹HNMR (proton nuclear magnetic resonance), 2D NMR, and LC-MS (liquid chromatography-mass spectrometry). <strong>Results:</strong> According to morphological and biochemical properties as well as ITS rDNA sequencing, we identified an isolate of <em>Aspergillus flavus</em>. The ethyl acetate fraction of the fermentation medium containing membrane active metabolites showed antimicrobial effects against different bacterial and yeast indicator strains. One metabolite from these active extracts was finally identified. <strong>Conclusion: </strong>Membrane active fraction produced by <em>Aspergillus</em> strain in this research demonstrated antimicrobial activities against bacteria and yeast strains. Therefore, this metabolite can be considered as a potential antimicrobial membrane active agent. Aspergillus, Membrane activity, Natural products 121 128 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-1-747&slc_lang=en&sid=1 Parisa Azerang 0000-0002-9851-2658 No Drug Design and Bioinformatics Unit, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran Vahid Khalaj 0000-0003-1621-6394 No Medical Biotechnology Departments, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran; Farzad Kobarfard 0000-0001-5528-2998 No Department of Medicinal Chemistry, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran Parviz Owlia 0000-0002-5981-3781 No Molecular Microbiology Research Center, Faculty of Medicine, Shahed University, Tehran, Iran Soroush Sardari 0000-0003-2080-7402 Yes Drug Design and Bioinformatics Unit, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran Sahar Shahidi 0000-0003-4015-8411 No Drug Design and Bioinformatics Unit, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran