Polysaccharides from Zanthoxylum bungeanum maxim Pericarp: In Vivo Absorption, in Vitro Simulated Digestion, Fecal Fermentation Characteristics, and Their Effects on Gut Microbiota and Metabolites

Polysaccharides from the pericarp of Zanthoxylum bungeanum maximus (PPZM) exhibit diversified bioactive properties. This study systematically investigated the absorption, simulated digestion characteristics, fecal microbiota fermentation behaviors of PPZM, as well as their modulatory effects on gut microbiota composition and metabolites. Findings suggested that PPZM were neither absorbed nor destroyed in the gastrointestinal tract and could reach the large intestine undamaged. PPZM were gradually degraded by the fecal microflora, generating short-chain fatty acids. It is worth noting that PPZM exhibited prebiotic activity by significantly enhancing the abundance of the commensal microbiota, while markedly inhibiting the pathogenic bacteria within the intestinal ecosystem. In addition, the metabolites that came from the gut microbiota exerted a significant influence on the metabolic pathways associated with tryptophan, histidine, and pantothenate and CoA biosynthesis. These findings collectively highlight PPZM's potential as a functional prebiotic for regulating intestinal homeostasis through microbiota modulation and metabolic pathway influence.