Isolation, Purification, and Characterization of an Arabinogalactan from a Red Wine

A polysaccharide originating from grape was purified from a young red wine by affinity, gel permeation, and ion exchange chromatography. Methylation structural analysis and enzymatic degradation by an α-L-arabinofuranosidase showed that this polysaccharide is an arabino-3,6-galactan built of (1 → 3)-galactan inner chains carrying (1 → 6)-galactan chains heavily substituted at positions 3 and 4 by single terminal α-L-arabinofuranose residues. This wine arabinogalactan has a low viscosity and a weight-average molecular weight (MW) of 178000.