| Title | Singlet oxygen quenching by dietary carotenoids in a model membrane environment. | | Author(s) | Cantrell A, McGarvey DJ, Truscott TG, Rancan F, Böhm F | | Institution | School of Chemistry and Physics, Lennard-Jones Laboratories, Keele University, Staffordshire, ST5 5BG, UK. | | Source | Arch Biochem Biophys 2003 Apr 1; 412(1):47-54. | | MeSH | 1,2-Dipalmitoylphosphatidylcholine
Antioxidants
Carotenoids
Cell Membrane
Deuterium Oxide
Kinetics
Lipid Metabolism
Lipids
Liposomes
Lutein
Membranes, Artificial
Models, Chemical
Oxygen
Time Factors
Xanthophylls
beta Carotene
| | Abstract | The ability of several dietary carotenoids to quench singlet oxygen in a model membrane system (unilamellar DPPC liposomes) has been investigated. Singlet oxygen was generated in both the aqueous and the lipid phase, with quenching by a particular carotenoid independent of the site of generation. However, singlet oxygen quenching is dependent on the carotenoid incorporated; xanthophylls exhibit a marked reduction in efficiency compared to the hydrocarbon carotenoids. Lycopene and beta-carotene exhibit the fastest singlet oxygen quenching rate constants (2.3-2.5 x 10(9)M(-1)s(-1)) with lutein the least efficient (1.1 x 10(8)M(-1)s(-1)). The other carotenoids, astaxanthin and canthaxanthin, are intermediate. Zeaxanthin exhibits anomalous behavior, and singlet oxygen quenching decreases with increasing amounts of zeaxanthin, leading to nonlinear plots for the decay of singlet oxygen with zeaxanthin concentration. Such differences are discussed in terms of carotenoid structure and their influence on the properties of the lipid membrane. The formation of aggregates by the polar carotenoids is also proposed to be of significance in their ability to quench singlet oxygen. | | Language | eng | | Pub Type(s) | Journal Article
Research Support, Non-U.S. Gov't
| | PubMed ID | 12646267 |
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