Structural studies of water-soluble polysaccharides of an edible mushroom, Termitomyces eurhizus. A reinvestigation Original Research Article

The structure of two polysaccharides isolated from the hot aqueous extract of fruiting bodies of the mushroom, Termitomyces eurhizus, have been reinvestigated. These consist of two homogeneous fractions PS-I and PS-II. PS-I contains only d-glucose as the monosaccharide constituent. From methylation analysis and periodate oxidation studies, followed by GLC–MS analysis the linkages, the sugar units in PS-I were identified as (1 → 3)-d-Glcp and (1 → 6)-d-Glcp. PS-II contains d-glucose, and the mode of linkage of d-glucose was identified as (1 → 6)-d-Glcp. Finally, the following possible structures of the polysaccharides were assigned using 1H, 2D-COSY, TOCSY, NOESY and 13C NMR spectral analysis: