title: Structure elucidation of a major fucopyranose-rich heteropolysaccharide (STP-II) from Sargassum thunbergii.
abstract: A crude polysaccharide was extracted from the edible algae S. thunbergii. DEAE-Sepharose CL-6B column chromatography was used to separate and purify a major polysaccharide STP-II (63.75%) from the crude polysaccharide. STP-II was found to be a homogeneous polysaccharide with a single peak by high-performance size-exclusion chromatography with a Sugar KS-804 column, have a molecular weight of 550 kD, and consist mainly of fucose, xylose, galactose, glucose and glucuronic acid. The structural assignment of STP-II was carried out using Fourier transform infrared spectroscopy analysis, periodate oxidation-smith degradation, partial hydrolysis with acid, methylation analysis and nuclear magnetic resonance studies, and the repeating unit of STP-II was thus determined. The result indicated that (1→3)-linked-fucose, (1→3)-linked-xylose and (1→3)-linked-galactose formed the major components of the main-chain structure, and the branch ratios were 17.5%. The branching and terminal residues were (1→2)-linked-glucuronic acid, (1→4)-linked-glucose, (1→)-linked-xylose and (1→)-linked-4-O-acetyl-glucose, respectively.
authors.affiliation: Huaqiao University, Department of Bioengineering and Biotechnology, Xiamen 361021, China.
authors.forename: Dianhui
authors.initials: D
authors.lastname: Luo
authors.affiliation: Huaqiao University, Department of Bioengineering and Biotechnology, Xiamen 361021, China.
authors.forename: Xiumei
authors.initials: X
authors.lastname: Yuan
authors.affiliation: Huaqiao University, Department of Bioengineering and Biotechnology, Xiamen 361021, China.
authors.forename: Yawei
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: Huaqiao University, Department of Bioengineering and Biotechnology, Xiamen 361021, China.
authors.forename: Kaiying
authors.initials: K
authors.lastname: Nie
authors.affiliation: Huaqiao University, Department of Bioengineering and Biotechnology, Xiamen 361021, China.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Li
authors.affiliation: Huaqiao University, Department of Bioengineering and Biotechnology, Xiamen 361021, China. Electronic address: zhaojingwang1203@qq.com.
authors.forename: Zhaojing
authors.initials: Z
authors.lastname: Wang
mesh_terms: D002240:Carbohydrate Sequence; D006868:Hydrolysis; D008745:Methylation; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010504:Periodic Acid / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D066244:Proton Magnetic Resonance Spectroscopy; D044647:Sargassum / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014269:Trifluoroacetic Acid / Q000737:chemistry
chemical_list: D011134:Polysaccharides; D010504:Periodic Acid; D014269:Trifluoroacetic Acid
keywords: Nuclear magnetic resonance experiments; S. thunbergii; Structural analysis