Functional Polysaccharide from Ficus hirta Vahl: Digestive Properties, Anti-Inflammation, and Effect on Gut Microbiota In Vitro

Ficus hirta Vahl is frequently utilized as an herbal ingredient in tonics, renowned for its abundant polysaccharide content and bioactive properties. However, the functional properties and impact of F. hirta Vahl polysaccharides (FHVPs) on the gut microbiota remain unclear. In this study, a polysaccharide, FHVP-3, was purified and identified as a nonstarch polysaccharide. Subsequently, the molecular weights, major chemical constituents, and monosaccharide compositions of FHVP-3 were characterized. Simulated digestion results indicated that FHVP-3 exhibits excellent stability in digestive juice. Furthermore, the effects of FHVP-3 on the gut microbiota were examined by using high-throughput sequencing technology, revealing an enrichment of Faecalibacterium, Bifidobacterium, Bacteroides, Phascolarctobacterium, and Blautia. Moreover, FHVP-3 suppressed the abundance of opportunistic pathogenic genera such as Dorea, Clostridium XIVa, and Desulfovibrio, thus preserving the gut microbial diversity. As a fermentable substrate, FHVP-3 also increased the concentrations of short-chain fatty acids, including acetate, propionate, and butyrate. FHVP-3 exhibited significant antioxidant activity and a significant anti-inflammatory effect on lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. In summary, we successfully purified and obtained the bioactive polysaccharide FHVP-3, and our findings confirm its prebiotic effects through modulation of the gut microbiome and anti-inflammatory activity in vitro.