A reticuloendothelial system-activating arabinoxylan from the bark of Cinnamomum cassia

A neutral polysaccharide, named cinnaman AX, was isolated from the dried bark of Cinnamomum cassia Blume. It was homogeneous on electrophoresis and gel chromatography. It is composed of L-arabinose: D-xylose in the molar ratio of 4:3, and its molecular weight was estimated to be about 1.0 x 10(6). Methylation analysis, carbon-13 nuclear magnetic resonance and controlled Smith degradation studies enabled elucidation of its structural features. It showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test.