Structural characterization of a branched (1 → 6)-α-mannan and β-glucans isolated from the fruiting bodies of Cantharellus cibarius

A comprehensive characterization of polysaccharides from the chanterelle was performed. Experiments included both linkage analysis by methylation and GC-MS, monosaccharide composition analysis by methanolysis, SEC-MALLS and several NMR experiments including COSY, HSQC, TOCSY, HSQC-TOCSY, NOESY, and HMBC. A 671 kDa (1 -> 6)-linked alpha-D-mannan with single and short (1 -> 2)-linked side chains (WCcF1b) was isolated from the hot water extract, after protease treatment and fractionation by size exclusion chromatography. The hot 1 M NaOH extract contained two types of beta-glucan; a water soluble (1 6)-linked beta-D-glucan with single and short (1 -> 3)-linked beta-glucan side chains (ACcSw) and a less branched (1 3)-linked beta-D-glucan (ACcIw/ACcId), proposed to contain short side chains in 0-4. Chemical shifts assignments of the alpha-mannan and beta-glucan are presented as well as chemical shift values obtained from a (1 6)/(1 3)-beta-D-glucan derived from Saccharomyces cerevisiae which was used as reference. (C) 2016 Elsevier Ltd. All rights reserved.