A heteropolysaccharide from an edible hybrid mushroom pfle 1p: structural and immunostimulating studies

Abstract

A water-soluble heteropolysaccharide (PS-I) having molecular weight ~2.1×10(5) Da was isolated from hot aqueous extract of the fruit bodies of hybrid mushroom pfle 1p. The hybrid mushroom pfle 1p was obtained through intergenic protoplast fusion between Pleurotus florida and Lentinula edodes. The heteropolysaccharide contained D-glucose, D-galactose, and D-mannose in a molar ratio of nearly 4:2:1. The structural investigation of PS-I has been carried out using sugar and methylation analyses as well as 1D/2D NMR experiments ((1)H, (13)C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HSQC, and HMBC). Based on the results of these experiments, the repeating unit of the PS-I was established as: [structure: see text]. PS-I showed in vitro macrophage activation by NO production and also stimulated splenocytes and thymocytes.