title: In vitro antioxidant activities of sulfated polysaccharide ascophyllan isolated from Ascophyllum nodosum.
abstract: Antioxidant activities of sulfated polysaccharide ascophyllan from Ascophyllum nodosum was investigated in vitro by various assays, and compared with those of fucoidan. A chemiluminescence (CL) analysis using a luminol analog, L-012, showed that ascophyllan scavenges superoxide, and the activity is greater than fucoidan. However, in the presence of 10μg/ml of ascophyllan or 10μg/ml and 100μg/ml of fucoidan, slightly enhanced CL-responses were observed. Since EDTA-treatment resulted in disappearance of the enhancement effects, it was suggested that metal ions especially iron ions in the polysaccharides might be involved in this phenomenon. In fact, metal element analysis revealed that ascophyllan and fucoidan inherently contain iron and other metal elements. EDTA-treatment resulted in significant increase in Fe(2+)-chelating activities of these polysaccharides. In an electron spin resonance (ESR)-spin trapping analysis in which direct UV-radiation to hydrogen peroxide was used as a source of hydroxyl radical, ascophyllan and fucoidan showed potent hydroxyl radical scavenging activity with similar extent. Reducing power of ascophyllan was stronger than that of fucoidan. Our results indicate that ascophyllan can exhibit direct and potent antioxidant activity.
authors: Division of Biochemistry, Faculty of Fisheries, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, Nagasaki 852-8521, Japan.
authors: Ryogo
authors: R
authors: Abu
authors: Zedong
authors: Z
authors: Jiang
authors: Mikinori
authors: M
authors: Ueno
authors: Takasi
authors: T
authors: Okimura
authors: Kenichi
authors: K
authors: Yamaguchi
authors: Tatsuya
authors: T
authors: Oda
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification; D044646:Ascophyllum / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D006861:Hydrogen Peroxide / Q000037:antagonists & inhibitors; D017665:Hydroxyl Radical / Q000037:antagonists & inhibitors; D007501:Iron / Q000737:chemistry*; D007502:Iron Chelating Agents / Q000737:chemistry* / Q000302:isolation & purification; D008163:Luminescent Measurements; D008165:Luminol / Q000031:analogs & derivatives; D010084:Oxidation-Reduction; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D013481:Superoxides / Q000037:antagonists & inhibitors
chemical_list: D000975:Antioxidants; D007502:Iron Chelating Agents; D011134:Polysaccharides; C058519:ascophyllin; D013481:Superoxides; C081614:L 012; D017665:Hydroxyl Radical; D008165:Luminol; C007789:fucoidan; D004492:Edetic Acid; D006861:Hydrogen Peroxide; D007501:Iron