Structural investigation of oxalate-soluble rapeseed (Brassica campestris) polysaccharides. 3. An arabinan

An arabinan isolated from rapeseed was shown by sedimentation studies to be essentially homogeneous, and methylation analysis revealed a highly branched structure. Hydrolysis of the methylated polysaccharide yielded 2,3,5-tri-O-methyl-L-arabinose (11 mol.), 2,3-di-O-methyl-L-arabinose (7 mol.), 3-O-methyl-L-arabinose (trace), 2-O-methyl-L-arabinose (7 mol.), and L-arabinose (2 mol.). Periodate-oxidation data substantiate the methylation results. The general, structural features of the arabinan are discussed.