脂质体环境中类胡萝卜素自由基阳离子的表征：与维生素C的相互作用

Characterisation of carotenoid radical cations in liposomal environments: interaction with vitamin C.

作者信息

Burke M, Edge R, Land E J, Truscott T G

机构信息

School of Chemistry and Physics, Lennard-Jones Laboratories, Keele University, Staffordshire, UK.

出版信息

J Photochem Photobiol B. 2001 Apr;60(1):1-6. doi: 10.1016/s1011-1344(01)00111-7.

DOI:10.1016/s1011-1344(01)00111-7

PMID:11386675

Abstract

Pulse radiolysis was used to generate the radical cations of beta-carotene and two xanthophylls, zeaxanthin and lutein, in unilamellar vesicles of dipalmitoylphosphatidyl choline. The rate constants for the reaction (repair) of these carotenoid radical cations with the water-soluble vitamin C were found to be similar (approximately 1x10(7) M(-1) s(-1)) for beta-carotene and zeaxanthin and somewhat lower (approximately 0.5x10(7) M(-1) s(-1)) for lutein. The results are discussed in terms of the microenvironment of the carotenoids and suggest that for beta-carotene, a hydrocarbon carotenoid, the radical cation is able to interact with a water-soluble species even though the parent hydrocarbon carotenoid is probably entirely in the non-polar region of the liposome.

摘要

采用脉冲辐解技术在二棕榈酰磷脂酰胆碱单层囊泡中生成β-胡萝卜素、两种叶黄素（玉米黄质和叶黄素）的自由基阳离子。发现这些类胡萝卜素自由基阳离子与水溶性维生素C反应（修复）的速率常数，β-胡萝卜素和玉米黄质相似（约1×10⁷ M⁻¹ s⁻¹），而叶黄素稍低（约0.5×10⁷ M⁻¹ s⁻¹）。根据类胡萝卜素的微环境对结果进行了讨论，结果表明，对于烃类类胡萝卜素β-胡萝卜素而言，尽管母体烃类类胡萝卜素可能完全处于脂质体的非极性区域，但自由基阳离子仍能够与水溶性物质相互作用。