Evaluation of probiotic, antibacterial and safety properties of Lacticaseibacillus rhamnosus JCM 1136

Probiotics are non-pathogenic and beneficial bacteria that contribute to improving digestive health, preventing various types of cancer, and boosting the body's immune system, among other benefits. The aim of this study was to investigate the probiotic potential and antimicrobial activity of the strain Lacticaseibacillus rhamnosus JCM 1136. In this research, the probiotic and safety characteristics of the strain were assessed, including acid resistance at pH 2, 3, and 4, bile resistance (0%, 0.3%, 0.5%, and 0.7% bile salt concentration), hydropHobicity, potential for producing DNase enzyme and biogenic amines, hemolytic activity, antioxidant activity, cholesterol absorption capacity, and resistance to common antibiotics. The antimicrobial effect of the strain against pathogenic bacteria (Shigella dysenteriae, Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, Listeria innocua, and Bacillus cereus) was evaluated using the agar well diffusion and disk diffusion methods. The results showed that L. rhamnosus JCM 1136 exhibited survival capability at different pH levels. The growth of the strain decreased with increasing bile salt concentration. L. rhamnosus JCM 1136 showed intermediate to the antibiotic Ampicillin and sensitivity to other antibiotics. The hydropHobicity, antioxidant activity by DPPH and ABTS methods, and cholesterol absorption capacity of the strain were 50.0 ± 50.53%, 50.0 ± 23.44%, 62.0 ± 50.48%, and 43.0 ± 55.41%, respectively. No production of DNase enzyme, biogenic amines, or hemolytic activity was observed in the strain. L. rhamnosus JCM 1136 exhibited a greater antimicrobial effect against Gram-positive bacteria. The results indicate that L. rhamnosus JCM 1136 possesses desirable probiotic characteristics and can be used in the production of probiotic food products.