Structural investigation of water-soluble polysaccharides extracted from the fruit bodies of Coprinus comatus

Water-soluble polysaccharide material, extracted from the stipes of the fruit bodies of Coprinus comatus by hot water, was fractionated by sequential weak anion-exchange and size-exclusion chromatography. The relevant fractions were subjected to structural analysis, including (D/L) monosaccharide/methylation analysis and 1D/2D NMR spectroscopy. Besides the disaccharide alpha,alpha-trehalose [alpha-D-Glcp-(1 <-> 1)-alpha-D-Glcp], high-molecular-mass alpha-D-glucans (the most abundant component) consisting of [-> 4)-alpha-D-Glcp-(1 ->](n) backbones with similar to 10% branching at C-6 by terminal alpha-D-Glcp-(1 -> 6)- or alpha-D-Glcp-(1 -> 6)-alpha-D-Glcp-(1 -> 6)- units, lower-molecular-mass linear beta-D-glucans consisting of [-> 6)-beta-D-Glcp-(1 ->](m) sequences, and a lower-molecular-mass pentasaccharide-repeating alpha-L-fuco-alpha-D-galactan, {-> 6)-alpha-D-Galp-(1 -> 6)-[alpha-L-Fucp-(1 -> 2)-]alpha-D-Galp-(1 -> 6)-alpha-D-Calp-(1 -> 6)-alpha-D-Galp-(1 ->}(p), were found to be present. (C) 2012 Elsevier Ltd. All rights reserved.