摘 要:
目的研究还原型谷胱甘肽(GSH)、半胱氨酸(Cys)、维生素C(VC)和亚铁离子(Fe2+)等常见还原性物质对五价无机砷[As(Ⅴ)]的还原作用及特点。方法模拟体内环境建立还原体系[37℃、pH7.0的磷酸盐缓冲液、3μmol/L As(Ⅴ)、60mmol/L巯基化合物(GSH和Cys)、0-30mmol/L VC、0-40mmol/LFe^2+],采用高效液相色谱-氢化物发生-原子荧光法(HPLC-HG-AFS)检测各种反应过程中的三价无机砷[As(Ⅲ)]和As(Ⅴ)。结果As(Ⅴ)还原率和As(Ⅲ)生成率随GSH浓度增加(0~60mmol/L)而增加;当GSH浓度为60mmol/L时,As(Ⅴ)还原率和As(Ⅲ)生成率达到峰值;随着GSH浓度继续增加(60~80mmol/L),As(Ⅴ)还原率和As(Ⅲ)生成率反而下降;巯基化合物中的巯基(-SH)在还原As(Ⅴ)过程中起关键作用,60mmol/L的-SH反应30分钟后As(Ⅴ)还原率达到60%,As(Ⅴ)还原率与-SH的具体存在形式(GSH或Cys)无关;单独VC或Fe^2+不能还原As(Ⅴ),但是当VC浓度大于10mmol/L或Fe2+浓度大于20mmol/L时,可以增加60mmol/L的-SH的还原作用(P〈0.01)。结论巯基化合物中的-SH可以非酶促还原As(Ⅴ),VC和Fe^2+可以增强-SH的还原作用。[著者文摘]
文章出处:
《卫生研究》-2008年37卷1期 -19-21页
栏目信息:
文献标识码:
A
文章编号:
1000-8020(2008)01-0019-03
Study of the arsenate reducted by common reducing agents
FU Jingqi, XUE Peng, JIN Yaping, HE Miao, et al. (Department of Occupational Health, School of Public Health, China Medical University, Shenyang 110001, China)
Abstract:
Objective To study the role of glutathione(GSH), cysteine(Cys), vitamin C(VC) and ferrous ion(Fe^2+) in the reduction of arsenate [ As ( Ⅴ ) ] and the characteristic of reduction.Methods The reaction conditions [ ( 37 ℃, pH7.0 phosphate buffer) and the concentrations of As ( V ) ( 3μmol/L), GSH ( 60mmol/L), Cys ( 60mmol/L), VC (0 - 30mmol/L) and Fe^2+ (0 - 40mmol/L) ] were simulated in vitro. Arsenite[As( Ⅲ ) ] and [As( Ⅴ ) ] were determined by the high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry(HPLC-HG-AFS). Results The reduction, of As( Ⅴ ) and As( Ⅲ) formation, increased with the concentration, of GSH(0 - 60mmol/L), and reached a maximum values at the concentration of 60mmol/L GSH, then decreased with the concentration of(60- 80mmol/L) GSH. -SH in suffhydryl compound, could play an important role in the reduction of As( Ⅴ ), and at the concentration of 60mmol/ L -SH(both GSH and Cys) could reduce 60% of As( Ⅴ ) to As( Ⅲ) for 30 min. VC or Fe^2+ could not reduce As( Ⅴ ) alone, but when the concentration of VC or Fe^2+ reached to 10mmol/L or 20mmol/L, they could have a significantly synergistic effect with 60mmol/L -SH on the reduction of As(Ⅴ ) ( P 〈 0.01 ). Conclusion -SH could reduce As( Ⅴ ) alone without any reductase. VC and Fe^2+ could have a synergistic effect with -SH on the reduction of As( V ).[著者文摘]
Key words:
arsenate, glutathione, cysteine, vitamin C, ferrous ion
基金资助:
国家自然科学基金重点项目(No.30530640)

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