Isolation, Structural Analysis and Anti‐Inflammatory Activity of a Polysaccharide from Ilex cornuta Fruits

Abstract

In the present study, a polysaccharide from Ilex cornuta fruits (LCFP‐3) was obtained by hot water extraction, Diethyaminoethyl cellulose‐52 (DEAE‐52) chromatography column and Sephadex G‐100 gel column purification. Its structural characteristics were further explored using high performance anion exchange chromatography (HPAEC), gas chromatography and mass spectrometry (GC/MS), scanning electron microscopy (SEM), Fourier transform infrared (FT‐IR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Monosaccharide composition analysis revealed LCFP‐3 contained mainly Galactose (31.92 %), Arabinose (25.87 %) and Galacturonic acid (23.35 %) while small percentage of Rhamnose, Glucose, Mannose and Xylose. Chemical composition analysis showed that the total sugar content of LCFP‐3 was 90.31 % and the protein content was 0.246 %. Gel permeation chromatography (GPC) analysis showed that its average molecular weight was 41.199 kDa. Structural analysis showed that LCFP‐3 may be composed of residues, T‐α‐Arap, T‐α‐Rhap, 1,3‐α‐Arap, 1,4‐α‐Arap, T‐β‐Galp, 1,4‐α‐GalpA(OMe), 1,4‐β‐Glcp, 1,3‐β‐Galp, 1,3,6‐β‐Manp, 1,6‐β‐Galp, 1,3,4‐β‐GalpA, 1,4,6‐β‐Manp, 1,3,6‐β‐Glcp, 1,2,3,4‐α‐Xylp. The anti‐inflammatory activity of LCFP‐3 was evaluated using lipopolysaccharide (LPS)‐induced RAW246.7 macrophages. The results showed that 1–200 μg/mL LCFP‐3 could dose‐dependently protect against LPS‐induced toxicity and 1 μg/mL LCFP‐3 could significantly inhibit LPS‐induced NO production. Therefore, LCFP‐3 exerted an anti‐inflammatory activity and has great potential as a functional ingredient.