A water-soluble polysaccharide (HCP) with a molecular mass of 6.7×105 Da determined by high performance
size-exclusion chromatography (HPSEC), was isolated fromthe fruit bodies of Sarcodon aspratus (Berk.) S. Ito., an
edible mushroom. HCP was elucidated as a liner glucan with a backbone structure of (1→6)-linked-α-Dglucopyranosyl
residues by interpretation of the composition analysis,methylation analysis, periodate oxidation
experiment, FT-IR, and NMR spectroscopy. Immunological activity evaluation using H3-thymidine incorporation
method revealed that HCP could significantly stimulate the proliferation of the cultured mice spleen lymphocyte
in a dose-dependentmanner. HCPmight be a potential immunomodulatorwhich can be used against pathogens
and tumors in health-care food or medicine. This is the first report on the detailed structure elucidation of the
polysaccharide from S. aspratus.