Structural Characterization and Anti-hyperuricemic Activity of Exopolysaccharides Secreted by Lactiplantibacillus plantarum-30

This study obtained a strain producing high yield of exopolysaccharide (EPS), which was identified as Lactiplantibacillus plantarum HZB-30. The strain produced 230.66 mg/L of EPS after fermentation for 28 h. The molecular mass of EPS produced by HZB-30 was 14639 Da, which was composed of several monosaccharides, such as glucose (37.76%) and galactose (19.15%). The EPS had high inhibitory activity against xanthine oxidase (XO) with an inhibition rate of 80.2%. After in vitro simulated digestion, the digestibility of the EPS was 20.7%, and 43.3% of the initial xanthine oxidase inhibitory activity remained. In an HK-2 cell model of hyperuricemia, the EPS at 20–60 μg/mL effectively decreased the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and IL-8 and inhibited the accumulation of uric acid. The findings from this study are both theoretically and practically important for the application of HZB-30-derived EPS to develop anti-hyperuricemic food products.