One‐electron reduction potentials of dietary carotenoid radical cations in aqueous micellar environments

FEBS Letters

McGarvey, David J.¹  Land, Edward J.²  Truscott, T.George¹  Edge, Ruth¹  Burke, Marc¹ 

[1] School of Chemistry and Physics, Lennard-Jones Laboratories, Keele University, Keele, Staffordshire ST5 5BG, UK;CRC Drug Development Group, Paterson Institute for Cancer Research, Christie Hospital, NHS Trust, Manchester M20 4BX, UK

关键词: Dietary carotenoid;    Radical cation;    One-electron reduction potential;    β-Carotene;    Lycopene;    Tryptophan;   

DOI  :  10.1016/S0014-5793(01)02601-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The one-electron reduction potentials of the radical cations of five dietary carotenoids (β-carotene, canthaxanthin, zeaxanthin, astaxanthin and lycopene) in aqueous micellar environments have been obtained from a pulse radiolysis study of electron transfer between the carotenoids and tryptophan radical cations as a function of pH, and lie in the range of 980–1060 mV. These values are consistent with our observation that the carotenoid radical cations oxidise tyrosine and cysteine. The decays of the carotenoid radical cations in the absence of added reactants suggest a distribution of exponential lifetimes. The radicals persist for up to about 1 s, depending on the medium.

【 授权许可】

Unknown