title: Structure-antioxidant relationships of sulfated galactomannan from guar gum.
abstract: Sulfated polysaccharides exerted potential biological property which was relative to degree of sulfation (DS), M(w), substitution position and chain conformation. In the present study, commercial guar gum was purified and its sulfated derivates with different DS and M(w) were synthesized. FT-IR and 13C NMR analysis indicated that C-6 substitution was predominant in sulfated samples compared with other positions. In the sulfation reaction, a sharp decrease in M(w) was observed. The d(f) values from 1.92 to 2.85 indicated that the -SO3H groups led to the relatively expanded conformation of sulfated polysaccharides. Antioxidant assays showed that sulfated polysaccharides had better antioxidant activities. The data obtained in in vitro models indicated that high DS and low M(w) showed the best antioxidant capacities.
authors.affiliation: Bioactive Products Engineering Research Center for Gansu Distinctive Plants, Northwest Normal University, Lanzhou 730070, China.
authors.forename: Xiaofang
authors.initials: X
authors.lastname: Wang
authors.forename: Junlong
authors.initials: J
authors.lastname: Wang
authors.forename: Ji
authors.initials: J
authors.lastname: Zhang
authors.forename: Baotang
authors.initials: B
authors.lastname: Zhao
authors.forename: Jian
authors.initials: J
authors.lastname: Yao
authors.forename: Yunpu
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000378:metabolism; D002236:Carbohydrate Conformation; D002850:Chromatography, Gel; D016166:Free Radical Scavengers / Q000494:pharmacology; D005685:Galactans / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000378:metabolism; D007477:Ions; D007501:Iron / Q000378:metabolism; D007502:Iron Chelating Agents / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008351:Mannans / Q000737:chemistry* / Q000494:pharmacology*; D008970:Molecular Weight; D010084:Oxidation-Reduction / Q000187:drug effects; D010851:Picrates / Q000378:metabolism; D053149:Plant Gums / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013329:Structure-Activity Relationship; D013463:Sulfuric Acid Esters / Q000737:chemistry* / Q000494:pharmacology*; D013481:Superoxides / Q000378:metabolism
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D005685:Galactans; D007477:Ions; D007502:Iron Chelating Agents; D008351:Mannans; D010851:Picrates; D053149:Plant Gums; D013463:Sulfuric Acid Esters; D013481:Superoxides; D017665:Hydroxyl Radical; C004931:1,1-diphenyl-2-picrylhydrazyl; D007501:Iron; C007894:guar gum