Xyloglucan from the leaves of Hymenaea courbaril

A fucosylated xyloglucan was isolated from the leaves of Hymenaea courbaril by alkaline extraction, followed by ethanol precipitation and ion-exchange chromatography. The isolated polysaccharide showed Glc:Xyl:Gal:Fuc in mola r ratio of 8:5:2.5:1 and [alpha](D)(25) +40.5 degrees. Composition and link age analyses, supported by NMR spectroscopic measurements, showed that the polysaccharide has a glucan backbone which is highly substituted at O-6 wit h D-xylopyranose residues, about a half of which are substituted at O-2 by D-galactopyranosyl units. Some of the galactose residues are further substi tuted by L-fucopyranose at O-2. The M-r, as determined by HPSEC, was 49,500 . (C) 2001 Elsevier Science Ltd. All rights reserved.