ISOLATION AND PROPERTIES OF A GLUCOMANNAN FROM THE WOOD OF RED MAPLE (ACER RUBRUM L.)

Abstract
A glucomannan has been isolated from the wood of red maple (Acer rubrum L.) in a yield corresponding to 92% of the mannose residues in this wood and with a ratio of mannose to glucose of 2:1. Partial hydrolysis of the polysaccharide yielded 4-O-β-D-mannopyranosyl-D-mannose, 4-O-β-D-mannopyranosyl-D-glucose, 4-O-β-D-glucopyranosyl-D-mannose, 4-O-β-D-glucopyranosyl-D-glucose, and O-β-D-mannopyranosyl-(l → 4)-O-β-D-mannopyranosyl-(1 → 4)-D-mannose. The methylated glucomannan on hydrolysis gave a mixture of di-O-methylhexoses, 2,3,6-tri-O-methyl-D-mannose, 2,3,6-tri-O-methyl-D-glucose, and 2,3,4,6-tetra-O-methyl-D-glucose in a mole ratio of 7:29:13:1. The methylated polysaccharide contained 55 hexose residues per average molecule, while the corresponding value for the nitrate derivative was 67. It is concluded that the glucomannan is composed of a minimum of 70 glucose and mannose residues linked together by (1 → 4)-β-glycosidic bonds to linear molecules. The glucose residues are probably interposed between two or three contiguous mannose residues.
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