Antimicrobial properties of lactic acid bacteria isolated from traditional yogurt and milk against Shigella strains

Abstract

Background: Lactic acid bacteria (LAB) are normal flora of the mouth, intestines and the female genital tract. They are also frequently found in meat, vegetables, and dairy products. Most of probiotic bacteria belong to the LAB group. Some probiotic LAB are useful in prevention and treatment of diarrheal diseases. The aim of this study was to investigate the antimicrobial properties of LAB isolated from traditional yogurt and milk against strains.Materials and methods: Forty LAB strains were isolated from traditional yogurt and milk. The antimicrobial activity of LAB against strains (eight , four ) was examined using the agar-well diffusion assay. LAB strains with antimicrobial effect against all strains were identified by 16S rRNA gene sequencing.Results: Six LAB strains inhibited the growth of all 12 strains. Y1-3, Y8-1 and Y2-2 were isolated from yogurt. M18-1, M4-3 and M19-1 were isolated from milk.Conclusion: This study showed that strains with good inhibitory activity against and could be isolated from traditional yogurt and milk.

Keywords

• lactic acid bacteria
• yogurt
• milk
• antimicrobial properties
• Shigella