CONSTITUTION OF AN ACIDIC XYLAN FROM TAMARACK (LARIX LARICINA)

Abstract

An acidic xylan isolated from tamarack wood contained arabinose, xylose, and uronic acid (1:17:3) and was homogeneous on examination by electrophoresis and sedimentation. Molecular weight estimations by four different methods showed a degree of polymerization of 20. Methylation and periodate oxidation showed that the xylan consisted of ca. 16 β-D-xylopyranose units joined by 1 → 4 glycosidic bonds with the possible occurrence of one 1 → 3 linkage. To this unbranched structure were attached as side branches, three single units of 4-O-methyl-D-glucuronic acid through C2 and one unit of L-arabofuranose through C3.