title: Fast repair of the poly G hydroxyl radical adduct by two phenylpropanoid glycosides.
abstract: The repair activities and the reaction mechanisms of two phenylpropanoid glycosides (PPGs), isolated from a herb used in Chinese folk medicine, towards the oxidizing hydroxyl radical adduct of poly G were studied with a pulse radiolytic technique. On pulse irradiation of a nitrous oxide saturated 4 mM aqueous solution of poly G containing one of the tested compounds, the transient absorption spectrum of the hydroxyl radical adduct of poly G decays with the formation of that of the phenoxyl radical of the tested compound within several tens microseconds after the electron pulse irradiation. The results indicated that there was a repair reaction between the hydroxyl radical adduct of poly G and the compounds tested. The rate constants for the repair reactions of poly G hydroxyl radical adducts by verbasicoside and cistanoside C were determined to be 1.4 and 1.0 x 10(9) M(-1) x s(-1), respectively.
authors.affiliation: Life Science School, Lanzhou University, Shanghai Institute of Nuclear Research, Chinese Academy of Sciences, Shanghai, P.R. China.
authors.forename: C Y
authors.initials: CY
authors.lastname: Huang
authors.forename: Y M
authors.initials: YM
authors.lastname: Shi
authors.forename: W F
authors.initials: WF
authors.lastname: Wang
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Jia
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: S D
authors.initials: SD
authors.lastname: Yao
authors.forename: N Y
authors.initials: NY
authors.lastname: Lin
authors.forename: R L
authors.initials: RL
authors.lastname: Zheng
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D002396:Catechols / Q000494:pharmacology*; D004260:DNA Repair / Q000187:drug effects*; D005960:Glucosides / Q000494:pharmacology*; D006027:Glycosides / Q000494:pharmacology*; D017665:Hydroxyl Radical / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry*; D010084:Oxidation-Reduction; D032262:Pedicularis / Q000737:chemistry*; D010636:Phenols / Q000494:pharmacology*; D011068:Poly G / Q000737:chemistry* / Q000528:radiation effects; D011675:Pulse Radiolysis; D013055:Spectrophotometry, Infrared; D059808:Polyphenols
chemical_list: D000975:Antioxidants; D002396:Catechols; D005960:Glucosides; D006027:Glycosides; D017665:Hydroxyl Radical; D016877:Oxidants; D010636:Phenols; D011068:Poly G; C471338:cistanoside C; C058956:acteoside; D059808:Polyphenols