Probiotic properties and safety assessment of lactic acid bacteria isolated from kajmak

Abstract

One hundred forty-one strains of lactic acid bacteria (LAB) were tested for probiotic features such as antimicrobial activities, autoaggregation ability, hydrophobicity of bacterial cell walls and ability to grow on and hydrolyze bile salts. Additionally, resistance to antibiotics and production of biogenic amines were performed as safety assessment of LAB strains. Five Lc. lactis ssp. lactis and six Lc. raffinolactis strains showed antibacterial activities against used indicator strains. Protein nature of antibacterial compounds was proven by the addition of pronase. Enterococcus durans strains had the highest degree of autoaggregation and hydrophobicity while the rest of the strains showed low degree for both characteristics. Lb. paracasei, Lb. plantarum, Ln. mesenteroides, En. faecium, En. faecalis and En. durans strains could growth on bile salts and some of them were able to hydrolyse them. Safety assessment of LAB indicates that many strains of enterococci were resistant to chloramphenicol, tetracycline, cephalosporin and to the lowest used concentration of erythromycin. The strains from other LAB genera were resistant to antibiotics used in lower concentration and in smaller numbers when compared to enterococci.

Keywords

• Lactic acid bacteria
• Probiotic properties
• Safety assessment