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Background and Objective: The generated genetic diversity in the microbial pathogens and drug resistant led to a growing interest to use herbal medicine. This study was carried out to determine the in vitro anti-bacterial activity of chloroform, ethyl acetate and hydroalcoholic extracts of Scilla persica Hausskn. Methods: In this laboratory study, chloroform, ethyl acetate and hydroalcoholic extracts were obtained from bulb of Scilla persica. The anti-microbial activity, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the extracts were evaluated on Staphylococcus aureus, Bacillus cereus and Escherichia coli using the disk diffusion (growth inhibition zone) and macro-dilution methods. Dimethyl sulfoxide (DMSO) was used as a negative control while nalidixic acid and ampicillin were used as positive control. Results: The maximum inhibition zone for ethyl acetate extract was 26.3±0.1 milimetre, 23.7±0.3 milimetre and 19.5±0.4 milimetre for Staphylococcus, Escherichia coli and Bacillus, respectively. The maximum inhibition zone of chloroform extract was found to be 16.4±0.2 milimetre and 14.9±0.3 milimetre for Staphylococcus and Bacillus, respectively. Conclusion: Antimicrobial activity of the chloroform and ethyl acetate extracts of bulb of Scilla persica on Escherichia coli, Staphylococcus aureus and Bacillus cereus are more effective compared to nalidixic acid and it is similar to ampicillin in in-vitro condition.

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Background and Objective: The emergence of Gram-positive and Gram-negative bacteria resistant to antibiotics is a crisis worldwide. In this study, the antibacterial effect of zinc oxide nanoparticles was evaluated on standard and food isolated strains of Salmonella enteritidis and Bacillus cereus.
Methods: This descriptive laboratory study, zinc oxide nanoparticles were prepared on zeolite materials, and zinc level was determined using XRF. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ZnO nanoparticles were determined using disc diffusion method.
Results: MIC value for all tested bacteria was 4 mg/ml and MBC values of standard and isolated strains of Salmonella enteritidis were 16 and 8 mg/ml, respectively, and for standard and isolated strains of Bacillus cereus was calculated in the range of 16 mg/ml.
Conclusion: Zinc oxide nanoparticles can inhibit Salmonella enteritidis and Bacillus cereus strains and may have a potential for its replacement with current preservatives to prevent food spoilage in industry.