title: An in vitro study of the structure-activity relationships of sulfated polysaccharide from brown algae to its antioxidant effect.
abstract: In this paper, the structure-activity relationships of chemically modified uronic acid polymer fragments from brown algae with regard to their antioxidant effects on H2O2-damaged lymphocyte were studied. The results indicated that the most potent antioxidant activity was obtained from the sulfated polysaccharide with ratio of mannuronate blocks (M-blocks) to guluronate blocks (G-blocks) of 3 to 1 and carboxyl residue unesterified. The sulfated G-blocks with esterified carboxyl residue also prevented lymphocyte from injury. However, the sulfated G-blocks bearing unesterified carboxyl residue hardly exerted antioxidant activity. These findings suggested that both M-blocks and esterified carboxyl residue were determinant structures in preventing lymphocyte from being oxidized by H202, indicating that the existence of M-blocks was more important in scavenging free radicals.
authors.affiliation: Institute of Marine Drug and Food, Ocean University of Qingdao, China.
authors.forename: J F
authors.initials: JF
authors.lastname: Hu
authors.forename: M Y
authors.initials: MY
authors.lastname: Gen
authors.forename: J T
authors.initials: JT
authors.lastname: Zhang
authors.forename: H D
authors.initials: HD
authors.lastname: Jiang
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D005562:Formazans / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry / Q000494:pharmacology; D008214:Lymphocytes / Q000187:drug effects; D051379:Mice; D018384:Oxidative Stress / Q000187:drug effects; D000459:Phaeophyceae / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D013463:Sulfuric Acid Esters / Q000737:chemistry / Q000494:pharmacology*; D013778:Tetrazolium Salts / Q000737:chemistry
chemical_list: D000975:Antioxidants; D005562:Formazans; D006603:Hexuronic Acids; D011134:Polysaccharides; D013463:Sulfuric Acid Esters; D013778:Tetrazolium Salts; C007896:guluronic acid; C079782:MTT formazan; C008324:mannuronic acid