Evaluation of the antimicrobial effect of molds isolated fromanimel feed on gram positive bacteria

Background and Aim : Secondary metabolites, also called specialised metabolites, toxins,secondary products, or natural products, are organic compounds produced by any lifeform, e.g.bacteria, fungi or plants, which are not directly involved in the normal growth, development, orreproduction of the organism. These compounds, isolated and have been used in modern medicinebecause of its antimicrobial effects.Methods : In this study secondary metabolites of Aspergillus flavus, Aspergillus fumigatus andpenicillium spp. isolated from moldy Livestock ration and its antimicrobial properties against ofStaphylococcus aureus was investigated.Results : Results of this study showed that the MIC was ۴۱۶.۶۶ ± ۱۴۴.۳۳, ۳۳۳.۳۳ ± ۱۴۴.۳۳ and۵۰۰ ± ۰.۰۰ (mg/ml) respectively for Aspergillus flavus, Aspergillus fumigatus and penicillium spp.secondary metabolites isolated. The MBC was ۵۰۰ ± ۰.۰۰, ۴۱۶.۶۶ ± ۱۴۴.۳۳ (mg/ml) respectivelyfor Aspergillus flavus and Aspergillus fumigatus; penicillium spp. had no any bactericidal effecton Staphylococcus aureus. Disk diffusion test shows no inhibitory zone in ۱۰۰, ۱۲۰ and ۱۵۰ μl forsecondary metabolites. Also There was no any inhibitory zone around secondary metabolites inwell diffusion in ۱۷۰, ۲۰۰ and ۲۲۰ μl.Conclusion : Based on the results; secondary metabolites of Aspergillus flavus, Aspergillusfumigatus and penicillium spp. especially Aspergillus flavus and Aspergillus fumigatus have theantibacterial effects on Staphylococcus aureus and can able be newest antibiotic against thismicroorganism.

کلیدواژه ها:

Secondary metabolites ، Aspergillus flavus ، Aspergillus fumigatus ، penicillium spp. ، Streptococcus pyogenes ، Staphylococcus aureus