Evaluation of the probiotic, anti-microbial, anti-biofilm, and safety properties of Levilactobacillus brevis Lb13H

Abstract

In this research, the probiotic potential, anti-microbial, anti-biofilm, and safety properties of Levilactobacillus brevis Lb13H were investigated. Also, Gaussian Process Regression (GPR) model was applied to predict some of experimental parameters. The strain demonstrated resistance to acidic pH, gastric and intestinal juices, and bile salts. Additionally, the strain exhibited 45.34% surface hydrophobicity, 36.55% auto-aggregation capacity, 26.30% co-aggregation, 10.20% adhesion to Caco-2 cells, 42.57% cholesterol removal, and 48.63% radical-scavenging properties. The probiotic strain was able to inhibit the adhesion of Listeria monocytogenes to intestinal cells by 31.30%, and its competitive inhibition percentage was 37.5%. Furthermore, the replacement of L. monocytogenes with the strain was measured at 22.10%. The most significant antimicrobial effect was observed against L. monocytogenes, while the least effect was noted against Rhizopus stolonifer. Haemolytic activity, DNase production, and biogenic amine production were not observed in the strain, which was also found to be sensitive to the antibiotics ciprofloxacin and chloramphenicol. The cell-free supernatant of L. brevis Lb13H effectively inhibited and degraded biofilm formation by L. monocytogenes, achieving effectiveness rates of 40.80% and 36.60% respectively. The results of modeling indicated that there is not any difference between actual and predicted data and GPR can predict the variables with high accuracy.