Abstract
A mucous polysaccharide, named Bletilla-glucomannan, has been isolated from the tubers of Bletilla striata REICHENBACH fil. It was homogeneous on glass-fiber paper electrophoresis and by ultracentrifugal analysis. The component sugars of it were D-mannose and D-glucose, and the molar ratio of them was 3 : 1. The molecular weight was estimated at 182000 by the measurement of osmotic pressure. Periodate oxidation and partial acid hydrolysis of it suggested that the polysaccharide is mainly composed of β-1→4 linked aldohexopyranose residues and it contains six aldohexose units per one end group on the average.
