CHARACTERIZATION OF A NOVEL GLUCAN, WHICH EXHIBITS RETICULOENDOTHELIAL SYSTEM-POTENTIATING AND ATNICOMPLEMENTARY ACTIVITIES, FROM THE RHIZOME OF CNIDIUM-OFFICINALE

A novel glucan, called cnidirhan SI, was isolated from the rhizome of Cnidium officinale MAKINO. It was homogeneous on electrophoresis and g el chromatography, and its molecular mass was estimated to be 1.3 x 10 (4). It is composed of D-glucose alone, in addition to small numbers o f O-acetyl groups. Methylation analysis, nuclear magnetic resonance an d enzymic degradation studies indicated it has a high-branched glucan type structure composed of alpha-1,4-linked D-glucopyranose residues w ith both 3,4- and 4,6-branching points. The glucan showed significant reticuloendothelial system-potentiating activity in a carbon clearance test, as well as pronounced anti-complementary activity. This substan ce is the first example of a branched alpha-glucan with phagocytosis-s timulating and anti-complementary activities.