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Background and Objective: The Candida albicans is an opportunistic fungi that can be pathogenic in patients suffering from diabetes and AIDS. This organism can cause various infections such as superficial of the skin and mucosa to deep tissue infections. In this study the antifungal effects of ZnO and SDS on Candida albicans in comparison with Fluconazole were investigated. Materials and Methods: This was an experimental study which evaluated the antifungal effects of biocide SDS and ZnO on Candida albicans by microbroth dilution assay in broth and agar medium. Minimum Inhibitory Concentration (MIC) was determinated for each inhibitor during colony count in comparison with control. Results: MIC of ZnO was 1.013-296 µg/ml and for SDS and Fluconazole were 0.001-0.56 and 0.062-128 µg/ml respectively. Conclusion: This study demonstrated antifungal activity of ZnO can be a candidates for the elimination of candida in medicine particular in medical instruments.

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Background and Objective: Ruta graveolens is a plant used in traditional medicine with variety of therapeutic effects. This study was done to evaluate the antimicrobial effect of hydro and alcoholic extracts of Ruta graveolens on 8 species of pathogenic bacteria. Methods: In this descriptive study, standard strains of Enterococcus faecalis, Staphilococcus aureus, Staphilococcus epidermis, Strptococcus pneumonia, Escherichia Coli, Klebsiella pneumonia, Salmonella typhi and Enterobacter Cloace were obtained from Iranian institute of scientific and industerial research center. The effect of hydro and hydroalcholic extracts of Ruta graveolens on the growth of bacteria was determined by disc diffusion and serial macro dilution methods. Minimum inhibitory concentration (MIC) for each extract was determined and the findings were compared with 8 common antibiotics including Co-trimoxazole, Oxycycline, Vancomycin, Erythromycin, Furazolidon, Tetracycline, amoxicillin / clavulanic acid and Ampicillin/sulbactam. Results: Hydro and hydroalcoholic extracts of Ruta graveolens did not show any inhibitory effect on growth of the pathogenic bacteria even in the presence of high concentration (3mg/ml). Conclusion: The extracts of arial organs of Ruta graveolens had no inhibitory effect on growth of the common human pathogenic bacteria.

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Background and Objective: The rise of antibiotic resistance particulary Methicillin resistance in pathogenic bacteria such as Staphylococcus aureus is found to be an emerging threat to human health especially in hospitals. Heavy metal nanoparticles such as Ag used for inhibition of this bacterium. This study was done to determine of minimum inhibitory concentration (MIC) Ag nanoparticle against Staphylococcus aureus which isolated in Gorgan, north of Iran and its relation with Methicillin resistance and source of bacteria.

Methods: In this descriptive – analytical study, the MIC Ag nanoparticle in 183 isolates of Staphylococcus aureus by microdilution method was determined. 30 isolates, based on mecA gene was considered as MRSA. Samples were collected from patients, nose of healthy carriers and foods. Compare the MIC of isolates based on Methicillin resistance, source of the bacteria and resistance to other antibiotics were assessed.

Results: Out of 183 samples MIC was varied from 1 to 16 µg/ml, and mean±std was 2.9±1.89 µg/ml. MIC mean of silver nanoparticles in isolated from foods were 2±0.7, isolared from healthy carriers were 4.1±2.4 and from patients were 3.4±2.1 µg/ml and were statically significant (P<0.05). MIC mean of silver nanoparticles in MSSA isolates are 3.9±2.3 and in MRSA isolates are 2.4±1.4 µg/ml that were statically significant (P<0.05). MIC mean of gentamycin resistant isolate were lower than sensitive one. But between MIC of silver nanoparticles and other antibiotics resistance was not significant statistically.

Conclusion: There is a relation between silver nanoparticle MIC, source of sample isolation, Methicillin and gentamycin resistance. Since MIC of silver nanoparticles on isolates of Methicillin resistant is low, the possibility of its use in the control of MRSA in hospital infections can be considered as a prime attention the Gentamycine.