Structural features of a water-soluble L-arabino-D-xylan from rye bran.

A water-soluble L-arabino-D-xylan, obtained from the chlorite holocellulose of de-lipidated, de-starched, and de-pectinated rye bran by ammoniacal extraction, was composed of L-Ara and D-Xyl in the molar ratio 7.8:10 and had Mw 36,500 and Mn 26,950. The backbone of the polysaccharide was shown to comprise (1----4)-linked beta-D-Xylp residues, with approximately 41% unsubstituted, approximately 33% 2- or 3-substituted, and approximately 26% disubstituted. Single alpha-L-Araf groups were attached to the xylan core; only a small proportion was 2-, 3-, or 5-linked.