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Background and Objective: Probiotics are beneficial organisms therapeutic within microbial flora. Shigella, Escherichia coli and Salmonella are the most common cause of intestinal infectious diseases that lead to morbidity and mortality in infant and children worldwide. The aim of this study was to evaluate anti-microbial activity of Lactobacillus acidophillus and Lactobacillus ruteri against entero-pathoges by in vitro and in vivo methods. Methods: In this experimental study, the therapeutic effect of the lactobacillus acidophilus ATCC 4356 and ruteri ATCC 23272 against Shigella sonnei ATCC 9290, Escherichia coli ATCC 25922 and Salmonella enterica BAA-708 were evaluated by in vitro (spot agar) and in vivo (BALB/c mice) methods. Weight improvment and survival rate in mice were recorded. Results: Lactobacillus acidophillus and ruteri had protective and therapeutic effect against diarrhea caused by pathogenic bacteria. Probiotics reduced the weight, colonization of pathogens and increased the survival rate of animals (P<0.05). Conclusion: Lactobacillus acidophillus and ruteri has anti-microbial activity and their consumption can be effective in the prevention and also the treatment of intestinal disease.

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Background and Objective: Nowadays, microorganisms have high resistance to antibiotics due to indiscriminate and unnecessary consumption. Treatment of infections caused by resistant bacteria has become difficult and expensive. Galls wild rose created by wasp's species Diplolepis mayri. This study was done to evaluate antibacterial activity of methanol, acetone and aqueous extracts of Wild Rose gall against Staphylococcus aureus and Enterococcus faecalis.
Methods: In this experimental laboratory study, the methanol, acetone and aqueous extracts of wild rose galls in 15.6, 31.3, 62.5, 125, 250 and 500 mg/dl were prepared by Soxhlet apparatus. Antibacterial activity of extracts was determined using well diffusion. MIC and MBC were determined by microdilution method. The active compounds of gall were evaluated by GC-MS.
Results: The inhibition zone of 500 mg/ml methanol, acetone and aqueous extracts of wild rose gall were 27.3, 26.7 and 20.0, respectively. The inhibition zone of wild rose gall was similar to imipenem (antibiotics). The extract concentration was related with antibacterial activity. The gall rose methanol extract showed the highest antibacterial effect. The MIC and MBC of methanol extract against Staphylococcus aureus and Enterococcus faecalis was 62.5, 31.3 mg/ml, respectively.
Conclusion: This study showed that aqueous, methanol and acetone extracts of wild rose galls have strong antibacterial activity.

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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.