Structural characterization and immunomodulatory activity of two novel polysaccharides derived from the stem of Dendrobium officinale Kimura et Migo

Abstract Two novel polysaccharide fractions, DOPW-1 and DOPW-2, were successfully isolated from the crude polysaccharide of Dendrobium officinale Kimura et Migo and purified using diethylaminoethyl (DEAE)-cellulose 52 and Sephacryl S-300HR column chromatography. Their average molecular weight, monosaccharide composition, and linkage were investigated and a possible structure of the repeat units was inferred. DOPW-1 and DOPW-2 exhibited better immunomodulatory activity than that of the major, water-soluble polysaccharide fraction (DOPW), significantly (P