Related Experiment Video For apo-carotenoids
Updated: Dec 27, 2025

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
Free Radical Mediated Oxidative Degradation of Carotenes and Xanthophylls
Raphael C Mordi1, Olabisi T Ademosun2, Christiana O Ajanaku2
1Department of Chemistry, Chrisland University, Ajebo Road, Abeokuta, Ogun State 110222, Nigeria.
Abstract:
This article reviews the excited-state quenching, pro-vitamin A activity and anticarcinogenicity of carotenes and xanthophylls in relation to their chemical structures. Excited-state quenching improved with the length of the conjugated chain structure. Pro-vitamin A activity was dependent on the presence of at least one beta-ionyl ring structure. The effectiveness of carotenoids as antioxidants depended on their ability to trap peroxyl radicals with production of resonance-stabilized carotenyl radicals. The products identified from oxidations of carotenes and xanthophylls with molecular oxygen and other oxidizing agents are presented. The free radical-mediated mechanisms that have been proposed to account for the different classes of products are reviewed.
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