Structural investigations of the neutral polysaccharide of Linum usitatissimum L. seeds mucilage

The heterogeneity of the purified water-soluble neutral fraction coming from the mucilage extract of the yellow flaxseed was investigated. After fractionation by size-exclusion chromatography, the analyse of the neutral monosaccharides composition showed a mixture of three major families of polymers. They were all identified as arabinoxylans with a constant A/X ratio of 0.24, but varying in their galactose and fucose residues in the side chains. Furthermore, the molecular weight (Mw) analysis acquired by multi-angle laser light scattered, revealed the association of two high Mw polymers [5.7 × 106 (11.1%) and 9.3 × 105 (42.4%) g mol−1] with a smaller one [3.2 × 105 g mol−1 (45.3%)].