title: Physicochemical characterization of a high molecular weight bioactive β-D-glucan from the fruiting bodies of Ganoderma lucidum.
abstract: A purified polysaccharide coded as GLP20 was obtained by precipitating a hot-water extract from Ganoderma lucidum fruiting bodies with 20% (V/V) ethanol. Its total carbohydrate content was 95.9%. Structural analysis showed that GLP20 was a β-(1→3)-linked d-glucan with a (1→6)-β-d-glucopyranosyl side-branching unit on every third residue. Cell culture study revealed that GLP20 can significantly increase NO production of RAW264.7 macrophages. The analysis of light scattering and high performance size exclusion chromatography (HPSEC) showed that the molecular weight and polydispersity of GLP20 was 3.75 × 10(6)Da and 1.36, respectively. GLP20 had a rigid chain conformation in aqueous solution. A conformation transition occurred in the alkaline solution with NaOH concentration larger than 0.15M. The transition from ordered structure to single chain happened when GLP20 was heated above 135°C in water solution and was irreversible as demonstrated by differential scanning calorimetry (DSC). GLP20 existed as random coils in DMSO.
authors.affiliation: Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, National Engineering Research Center of Edible Fungi, National R&D Center for Edible Fungi Processing, Shanghai 201403, China; Guelph Food Research Centre, Agriculture and Agri-Food Canada, 93 Stone Road. W., Guelph, Ontario N1G 5C9, Canada. Electronic address: woshialiu730@gmail.com.
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Liu
authors.forename: Jingsong
authors.initials: J
authors.lastname: Zhang
authors.forename: Qingjiu
authors.initials: Q
authors.lastname: Tang
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.forename: Qingbin
authors.initials: Q
authors.lastname: Guo
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.forename: Steve W
authors.initials: SW
authors.lastname: Cui
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D002460:Cell Line; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D048690:Fruiting Bodies, Fungal / Q000737:chemistry*; D032902:Ganoderma / Q000737:chemistry*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D008745:Methylation; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009005:Monosaccharides / Q000032:analysis; D009569:Nitric Oxide / Q000096:biosynthesis; D014867:Water / Q000737:chemistry; D047071:beta-Glucans / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D009005:Monosaccharides; D047071:beta-Glucans; D014867:Water; D009569:Nitric Oxide; D004121:Dimethyl Sulfoxide
keywords: Conformation; DSC; Ganoderma lucidum; HPSEC; Immunomodulation activity