جستجوی مقالات مرتبط با کلیدواژه « اثر ضد قارچی » در نشریات گروه « دامپزشکی »

Natural honey is a proper substrate to isolate probiotic bacteria. Characterization of probiotic and antifungal properties of microorganisms isolated from food ecosystems such as natural honey that have been less studied is an interesting task. In the present study, after molecular identification of a predominant lactic acid bacterium (LAB) isolated from the natural honey, its probiotic properties and antifungal effect were investigated. Then, the antibacterial (spot method) and antifungal (overlay method) activities of the LAB isolate were evaluated against some foodborne microorganisms. Sequencing results of the PCR products led to the identification of Enterococcus faecium. Survival rate of the isolate in simulated gastrointestinal conditions was equal to 20.68%, and its antibacterial and antifungal effects on Salmonella enterica and Aspergillus niger were also 31.06 and 32.35% inhibition, which were significantly (P<0.05) higher than the other foodborne indicators studied. Furthermore, the isolate had a proper antibiotic resistance profile, and it had no hemolytic activity. Auto-aggregation ability of the isolate was also equal to 32.34%, and its co-aggregation with Escherichia coli, S. enterica, Listeria monocytogenes and Bacillus cereus was 34.29, 21.35, 15.58 and 14.98%, respectively. Based on the results, it can be concluded that the E. faecium isolated from honey can be used as probiotic and/or protective culture in food industry.

Probiotic and antifungal properties of the yeasts isolated from fermented pseudo cereals have been rarely studied, yet. In the present study, after isolation of predominant yeasts isolated from fermented black rice, the yeast with the highest survival in simulated gastrointestinal conditions was selected for further studies. Then, the selected isolate was identified by PCR, and subsequently, its probiotic properties including antibacterial effects, antibiotic and antimycotic susceptibilities, aggregation, hydrophobicity and hemolytic potentials were also studied. Antifungal activity of the selected yeast was investigated against some of the foodborne fungi. Sequencing of the PCR products led to the identification of Rhodotorula mucilaginosa as the selected yeast isolate. The isolate maintained 84.39% of its survival in continues acid and bile treatment. Also, the inhibitory effect of the yeast isolate on Salmonella enterica was significantly (p<0.05) higher than the other foodborne bacteria. Yeast isolate had proper aggregation and hydrophobicity capabilities, and it was resistant to the antibiotics tested. Furthermore, the most inhibition of the yeast growth was observed in the presence of ketoconazole, while the selected yeast was resistant to propionate, sorbate, itroconazole and fluconazole. The studied yeast isolate had no hemolytic activity. The antifungal effect of the yeast isolate against Aspergillus flavus was also verified. In accordance with these results, the selected yeast isolate has a proper potential to use as a probiotic or protective culture in production of fermented foods.

Candida albicans is opportunistic yeast that may cause infection in predisposed individuals such as users of broad spectrum antibiotics. Increasing reports of candida strains resistance to common antifungal agents, has become a health concern. It is now clear that lactic acid bacteria can produce antimicrobial compounds with the ability to inhibit the growth of pathogenic microorganisms. The aim of this study was evaluation of antifungal effect of Lactobacillus plantarum and inhibitory effect on the production of germ tube in isolates of Candida albicans.
In this study antifungal effect of acidic and neutral supernatant of L. plantarum were evaluated using agar dilution method. All isolates obtained from mycology research center of veterinary medicine of Tehran university. The effect of supernatant (acidic and neutral) on production of germ tube in Candida albicans fluconazole resistance isolates from oral, vaginal and nail lesion with a control (no treatment) were determined in broth medium after 1, 2 and 3 h of incubation.
The average of germination of Candida albicans isolates nails, vagina and mouth treated with acidic supernatants were 3.48±0.87, 0 and 0 respectively. The germination of Candida albicans isolates treated with acidic supernatants significantly was reduced, compared with the control group (no treatment). Antifungal activity of acidic supernatant of L. plantarum against Candida albicans is very significant compared to neutral supernatant. Therefore, the use of L. plantarum is recommended for the prevention and treatment of infections caused by Candida albicans.