Probiotic Characterization of Limosilactobacillus fermentum Isolated from Local Yogurt: Interaction with Pathogenic Bacteria and Caco-2 Enteric Cell Line

The term "probiotic," which is relatively novel and means "for life," is typically used to refer to bacteria that include positive effects on humans and animals. In this study, probiotic characteristics of Limosilactobacillus fermentum IMAU70160, isolated from local yogurt were investigated.

In this study, molecular identification of a strain isolated from local yogurt was carried out by 16S rRNA gene analysis using 27FYM and 1492R universal primers. Probiotic potential of L. fermentum IMAU70160 was carried out.

Strain was resistant to low pH, bile salts and simulated gastrointestinal conditions. The strain cell surface hydrophobicity, auto-aggregation, co-aggregation, adhesion capacity, anti-adhesion effect, antioxidant activity and cholesterol removal ability were 44.49, 33.29, 20.11, 10.30, 19.16–42.40, 48.40 and 43.20%, respectively. Staphylococcus aureus and Escherichia coli were the most sensitive and the most resistant bacterial species to cell-free supernatant (CFS) of L. fermentum IMAU70160, respectively. The two aCFS and nCFS were capable of inhibiting growth of pathogens. In general, aCFS included a greater antimicrobial activity than that nCFS did. Similar results were observed in the modified double-layer method. It showed no hemolytic or DNase activity and was unable to generate biogenic amines. The strain was greatly sensitive to imipenem (22.10 mm), chloramphenicol (22.80 mm), nitrofurantoin (24.50 mm) and ciprofloxacin (28.20 mm) with inhibition zones.

Further studies are needed to verify biological and functional characteristics of L. fermentum IMAU70160-loaded food products.