title: Characterization of a bioactive polysaccharide from Ganoderma atrum: Re-elucidation of the fine structure.
abstract: The fine structure in terms of backbone and branch chain features of a bioactive polysaccharide from Ganoderma atrum (PSG-1) was re-elucidated systematically using high performance anion-exchange chromatography (HPAEC), methylation and GLC-MS analysis, and 1D & 2D NMR spectroscopy. Monosaccharide composition analysis revealed that PSG-1-F0.2fraction mainly consisted of glucose (73.8%) and glucuronic acid (15.3%), with small amount of mannose (5.7%) and galactose (5.2%). Based on methylation, multistep partial acid hydrolysis and NMR study, were proposed to substitute at the O-6 position of β-(1→3)-glucan. The small amount of mannose and galactose residues were considered to be from the other fraction in PSG which was very difficult to be separated from PSG-1-F0.2. This revised structure as an acidic β-(1→3, 1→6)-glucan is considered to be more accurate than the previous proposal of PSG-1.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, Jiangxi 330047, China; School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, Jiangxi 330047, China. Electronic address: spnie@ncu.edu.cn.
authors.forename: Shaoping
authors.initials: S
authors.lastname: Nie
authors.affiliation: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, N1G 5C9, Canada.
authors.forename: Steve W
authors.initials: SW
authors.lastname: Cui
authors.affiliation: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, N1G 5C9, Canada.
authors.forename: Ming
authors.initials: M
authors.lastname: Xu
authors.affiliation: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, N1G 5C9, Canada.
authors.forename: Huihuang
authors.initials: H
authors.lastname: Ding
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, Jiangxi 330047, China. Electronic address: myxie@ncu.edu.cn.
authors.forename: Mingyong
authors.initials: M
authors.lastname: Xie
mesh_terms: D002853:Chromatography, Liquid; D062610:Fungal Polysaccharides / Q000737:chemistry*; D032902:Ganoderma / Q000737:chemistry*; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009005:Monosaccharides
chemical_list: D062610:Fungal Polysaccharides; D009005:Monosaccharides
keywords: Fine structure; Ganoderma atrum; Methylation; NMR spectroscopy; Partial acid hydrolysis; Polysaccharide