Chemical characterization and wound healing property of a ß-D-glucan from edible mushroom Piptoporus betulinus.

A water-soluble ß-D-glucan was obtained from fruiting bodies of Piptoporus betulinus, by hot aqueous extraction followed by freeze-thawing procedure and dialysis. Its molar mass distribution and conformational behavior in solution was assessed by size-exclusion chromatography coupled with multiangle laser light scattering, showing a polysaccharide with an average molecular weight of 2.5 × 105 Da with a random coil conformation for molecular weights below 1 × 106 Da. Typical signals of ß-(1 → 3)-linkages were observed in NMR spectrum (δ 102.7/4.76; 102.8/4.74; 102.9/4.52; and δ 85.1/3.78; 85.0/3.77) and also signals of O-6 substitution at δ 69.2/4.22 and 69.2/3.87. The analysis of partially O-methylated alditol acetates corroborates the NMR results, indicating the presence of a ß-D-glucan with a main chain (1 → 3)-linked, substituted at O-6 by single-units of glucose. The ß-D-glucan showed no toxicity on human colon carcinoma cell line (Caco-2) up to 1000 µg mL-1 and promoted cell migration on in vitro scratch assay, demonstrating a potential wound healing capacity.