Exopolysaccharides (EPSs) synthesized by lactic acid bacteria (LAB) have garnered significant attention due to their potential health-promoting properties. In this study, we characterized and evaluated the biological activities of EPS produced by Limosilactobacillus reuteri MK1, a strain isolated from chicken intestines. The MK1 strain was identified using 16S rRNA gene sequencing. The structural characterization of the EPS was performed through Fourier-transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy followed by analysis of physicochemical properties. The EPS exhibited strong emulsifying activity, particularly with xylene (72.8%), as well as excellent water and hydrocarbon solubility. Antioxidant potential was assessed via DPPH and H₂O₂ radical scavenging assays, revealing concentration-dependent activities of 64% and 70%, respectively at a concentration of 10 mg/mL. The EPS also demonstrated notable antibacterial activity against tested pathogenic bacterial strains. Optimization of culture conditions enhanced EPS production, achieving a maximum yield of 585 mg/L after 33 hours of incubation. FTIR and NMR analyses confirmed the polysaccharide structure and identified key functional groups of the macromolecule. These results collectively demonstrate that the EPS from L. reuteri MK1 is a multifunctional biopolymer with versatile capabilities, including emulsification, radical scavenging, and pathogen inhibition, positioning it as a promising natural additive for food, pharmaceutical, or nutraceutical applications. Future research should focus on scaling production processes and exploring targeted applications in pharmaceutical and nutraceutical industries.

To Cite This Article: Hayat HF, Khurshid M, Rasool MH and Aslam B, xxxx. Characterization, antibacterial and antioxidant potential of exopolysaccharide produced by Limosilactobacillus reuteri MK1 isolated from poultry intestine. Pak Vet J. http://dx.doi.org/10.29261/pakvetj/2025.172