Anti-inflammatory and anti-pathogenic potential of Lacticaseibacillus rhamnosus IDCC 3201 isolated from feces of breast-fed infants

Objective: We investigated the anti-inflammatory and anti-pathogenic activities of Lacticaseibacillus rhamnosus IDCC 3201 isolated from the feces of breast-fed infants.Methods: Cell viability, nitric oxide (NO) production, and expression of inflammatory markers by L. rhamnosus IDCC 3201 were quantitatively analyzed in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. The antibacterial and antifungal activities of L. rhamnosus IDCC 3201 against various pathogens were also investigated.Results: Treatment of LPS-induced macrophages with cell-free supernatant of L. rhamnosus IDCC 3201 signifi-cantly decreased the expression levels of tumor necrosis factor (TNF-alpha) and interleukin-6 (IL-6). Nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) levels also significantly decreased in LPS-induced macrophages. Phenotypically, the treatment of L. rhamnosus IDCC 3201 reduced the production of nitric oxide (NO) in LPS-induced macrophages. Furthermore, L. rhamnosus IDCC 3201 was proven to have potent inhibitory activities against various pathogens responsible for inflammatory responses in the gastrointestinal tract (i.e., Bacillus ce-reus, Enterococcus faecalis, Staphylococcus aureus, and Salmonella Typhimurium), respiratory system (i.e., Strep-tococcus pneumoniae), and vagina (i.e., Candida albicans).Conclusion: L. rhamnosus IDCC 3201 has anti-inflammatory activity in terms of decreased expression of cytokines, inflammation-inducible enzymes in LPS-induced macrophages, and anti-pathogenic activity.