Isolation and genetic diagnosis of local isolate Enterococcus faecium with evaluation of inhibitory against bacterial pathogens

الملخص

Objective: Isolation the bacteria from food source has a probiotic characterization and evaluate the inhibitory activity against bacterial pathogens. Methods: Lactic acid bacteria from various sources are isolated by the MRS-CaCO₃Agar medium, the isolates were purified and microscopic, biochemical were tested. The antibacterial activity of cell free supernatant (CFS) against Bacillus subtilis , Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli also testing. The isolate was selected based on high inhibitory activity and genetic diagnosis were performed. Results: the highest inhibitory diameter against Gram-positive bacteria was recorded with a diameter of 13 mm to Staph aureus. The results showed that the bacterial isolate Gram positive, immobile, negative for catalyze, Esculin hydrolysis, and CO₂ production from glucose, grows at 10- 45^⸰C, 2- 6.5% Nacl, and at pH 4.5- 6.9. It had the ability to ferment of sucrose, mannitol, arabinose, sorbitol and xylose. The diagnosis of isolation has been genetically confirmed to the species Enterococcus faecium. Conclusion: The E. faecium can be considered as probiotics in a safe manner to adaptive immune, in addition to the possibility of using it as a potential source of natural antibacterial agent in food and pharmaceutical industries.