title: Characterization of antioxidant and antiglycation properties and isolation of active ingredients from traditional chinese medicines.
abstract: There is considerable interest in the isolation of more potent antioxidant compounds to treat diseases involving oxidative stress. Thirty-three traditional Chinese medicine (TCM) extracts were examined for their antioxidant activity using the 2,2'-azinobis[3-ethylbenzothiazoline-6-sulfonate] (ABTS) assay. Five extracts with high activity (Cratoxylum cochinchinense, Cortex magnoliae officinalis, Psoralea corylifolia L, Curculigo orchioides Gaertn, and Glycyrrhiza uralensis Fisch.) were selected for further characterization. C. cochinchinense outperformed other extracts in most of the assays tested except phospholipid peroxidation inhibition, where P. corylifolia L showed higher activity. C. cochinchinense was particularly potent in inhibiting the formation of advanced glycation end products on proteins and strongly inhibited hypochlorous acid-induced DNA damage. We attempted to isolate the active ingredients from C. cochinchinense and obtained an extract (YCT) containing at least 90% mangiferin as identified by HPLC and mass spectrometry. However, YCT showed significantly higher activity in assays of phospholipid peroxidation, inhibition of protein glycation, and superoxide (O(2)(?-)) and peroxynitrite (ONOO(-)) scavenging, as compared with mangiferin, suggesting that the nonmangiferin constituents of YCT contribute to its additional antioxidant activities.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, National University of Singapore, Singapore.
authors.forename: Soon Yew
authors.initials: SY
authors.lastname: Tang
authors.forename: Matthew
authors.initials: M
authors.lastname: Whiteman
authors.forename: Zhao Feng
authors.initials: ZF
authors.lastname: Peng
authors.forename: Andrew
authors.initials: A
authors.lastname: Jenner
authors.forename: Eu Leong
authors.initials: EL
authors.lastname: Yong
authors.forename: Barry
authors.initials: B
authors.lastname: Halliwell
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000737:chemistry; D052160:Benzothiazoles; D002851:Chromatography, High Pressure Liquid; D028084:Clusiaceae / Q000378:metabolism; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D006997:Hypochlorous Acid / Q000494:pharmacology; D015227:Lipid Peroxidation; D008055:Lipids / Q000737:chemistry; D013058:Mass Spectrometry; D008516:Medicine, Chinese Traditional; D008956:Models, Chemical; D009584:Nitrogen / Q000737:chemistry; D030421:Peroxynitrous Acid / Q000378:metabolism; D019800:Phenol; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism; D013451:Sulfonic Acids / Q000494:pharmacology; D013481:Superoxides / Q000737:chemistry / Q000378:metabolism; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000737:chemistry; D014969:Xanthine Oxidase / Q000737:chemistry / Q000378:metabolism; D044004:Xanthones / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D052160:Benzothiazoles; D008055:Lipids; D010743:Phospholipids; D013451:Sulfonic Acids; D044004:Xanthones; D013481:Superoxides; D030421:Peroxynitrous Acid; C013592:mangiferin; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D019800:Phenol; C002744:3-nitrotyrosine; D014443:Tyrosine; D006997:Hypochlorous Acid; D014969:Xanthine Oxidase; D009584:Nitrogen; D001205:Ascorbic Acid