Characterization of a pectic heteropolysaccharide isolated from persimmon peel and its anti-inflammatory activity

A main component, pectic polysaccharide (PPP-4), was isolated from persimmon peel. PPP-4 had the molecular weight of 56.48 kDa and primarily consisted of galacturonic acid, arabinose, galactose, rhamnose with the molar ratios of 60.80:32.12:3.67:2.20. The backbone of PPP-4 was formed by →4)-α-D-GalpA-(1→ and →2,4)-α-L-Rhap-(1→ with branches of →3)-α-L-Araf-(1→, and →3)-β-L-Galp-(1→, →5)-α-L-Araf-(1→, →3,5)-α-L-Araf-(1→ residues and terminals of 4-β/α-D-GalpA and T-α-L-Araf residues. Besides, PPP-4 consumption could relieve colonic pathological damage, inhibit the expression of proinflammatory cytokines (IL-1β, IL-6, and TNF-α) in serum, increase the fecal short chain fatty acids (SCFAs) and improve antioxidant capacity in dextran sodium sulfate (DSS)-induced colitis mice. Simultaneously, PPP-4 was revealed to regulate flora disorder, reduce the relative abundance of harmful microbe (Dubosiella, Odoribacter, Parasutterella, and Turicibacter, etc.) and increase the relative abundance of beneficial microbe (such as Akkermansia and Lactobacillus) in colitis mice. Overall, these data would furnish new theoretical basis for the structural information of PPP-4 and highlight its potentiality to be considered as a natural anti-inflammation reagent.