Structural investigation of a polysaccharide (DMB) purified from Dioscorea nipponica Makino

A water-soluble polysaccharide was isolated from the aqueous extract of Dioscored nipponica Makino. Compositional analysis, IR analysis, methylation analysis, and NMR studies (1H, 13C, 1H1H COSY, HSQC, and HMBC) revealed the presence of the following repeating unit in the polysaccharide: