Chemical analysis of a new fucoglucan isolated from an edible mushroom, Termitomyces robustus

A water-soluble fucoglucan, isolated from alkali-treated edible mushroom, Termitomyces robustus, consists of l-fucose and d-glucose in a molar proportion of 1:4. Structural investigation of the polysaccharide was carried out by using total hydrolysis, methylation analysis, and periodate oxidation followed by GLC–MS, and the final structure was determined using NMR experiments ( 1H, 13C, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC). On the basis of the above experiments it is concluded that the following repeating unit is present in the polysaccharide: [Display omitted]