title: Antioxidant activity of differently regioselective chitosan sulfates in vitro.
abstract: Differently regioselective chitosan sulfates were prepared according to Hanno Baumann's methods. Their antioxidant potencies were investigated employing various established in vitro systems, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH)/superoxide/hydroxyl radicals scavenging, reducing power, iron ion chelating and total antioxidant activity. All kinds of sulfated chitosans (HCTS, TSCTS, SCTS, TCTS) showed strong inhibitory activity toward superoxide radical by the PMS-NADH system compared to Vc. According to the above-mentioned order their IC50 were 0.012, 0.040, 0.015, 0.022 mg/mL, respectively, however, scavenging activity of Vc on superoxide radical was 68.19% at 2.0 mg/mL. Scavenging activity of superoxide radical was found to be in the order of HCTS>SCTS>TCTS>TSCTS>Vc. Furthermore, all kinds of sulfated chitosans exhibited strong concentration-dependent inhibition of deoxyribose oxidation. Except for HCTS, others had stronger scavenging activity on hydroxyl radical than Vc. Scavenging effect of TSCTS on 1,1-diphenyl-2-picrylhydrazyl radical was little lower than that of BHA, but better than that of others. All kinds of sulfated chitosans were efficient in the reducing power, especially TSCTS. TSCTS and TCTS showed considerable ferrous ion chelating potency. The data obtained in vitro models clearly establish the antioxidant potency of all kinds of sulfated chitosans. These in vitro results suggested the possibility that sulfated chitosans could be effectively employed as ingredient in health or functional food, to alleviate oxidative stress. However, comprehensive studies need to be conducted to ascertain the in vivo safety of sulfated chitosans in experimental animal models.
authors.affiliation: Institute of Oceanology, The Chinese Academy of Sciences, Qingdao 266071,China.
authors.forename: Ronge
authors.initials: R
authors.lastname: Xing
authors.forename: Huahua
authors.initials: H
authors.lastname: Yu
authors.forename: Song
authors.initials: S
authors.lastname: Liu
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhang
authors.forename: Quanbin
authors.initials: Q
authors.lastname: Zhang
authors.forename: Zhien
authors.initials: Z
authors.lastname: Li
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Li
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D048271:Chitosan / Q000737:chemistry / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000494:pharmacology*; D017665:Hydroxyl Radical / Q000737:chemistry; D007502:Iron Chelating Agents / Q000737:chemistry / Q000494:pharmacology; D013237:Stereoisomerism; D013481:Superoxides / Q000737:chemistry
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D007502:Iron Chelating Agents; C480355:chitosan sulfate; D013481:Superoxides; D017665:Hydroxyl Radical; D048271:Chitosan