Structural analysis and prebiotic properties of the polysaccharides produced by Lactiplantibacillus plantarum YT013

Exopolysaccharides (EPS) from Lactiplantibacillus plantarum YT013 were isolated, structurally characterized and evaluated for gastrointestinal stability and in vitro prebiotic potential. YT013-EPS-1 (57.51 kDa) demonstrated superior resistance to simulated gastrointestinal digestion and maintained structural integrity relative to YT013-EPS-2 (149.3 kDa). Both EPSs exhibited significantly increased antioxidant activity after digestion relative to their undigested forms. In an in vitro mouse fecal fermentation model, YT013-EPS-1 significantly increased SCFA production and promoted beneficial bacteria such as Phascolarctobacterium and Lactobacillus, while reducing potentially pathogenic genera such as Escherichia-Shigella and Acinetobacter. These microbial and metabolic shifts suggest that YT013-EPS-1 influences gut microbiota and promotes microbial metabolites associated with intestinal barrier function and host metabolic regulation. Notably, YT013-EPS-1 exerted more pronounced modulatory effects on gut microbiota composition and SCFA profiles than YT013-EPS-2. Collectively, these findings highlight the potential of YT013-EPS-1 as a prebiotic ingredient for modulating gut microbiota in vitro.