A glucan from an ectomycorrhizal edible mushroom Tricholoma crassum (Berk.) Sacc.: isolation, characterization, and biological studies.

A water soluble glucan of average molecular weight ∼1.74×10(5)Da was isolated from hot aqueous extract of the fruiting bodies of an ectomycorrhizal edible mushroom Tricholoma crassum (Berk.) Sacc. The structure of this glucan was elucidated on the basis of total hydrolysis, methylation analysis, Smith degradation, and 1D/2D NMR studies. Based on the above experiments the repeating unit of the glucan was established as: [formula see text]. This glucan showed macrophage activation in vitro by NO production in a dose dependent manner and strong splenocyte and thymocyte immunostimulation in mouse cell culture medium. It also exhibited good inhibition activity toward lipid peroxidation.