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Updated: Jul 19, 2025

Measurement of Carotenoids in Perifovea using the Macular Pigment Reflectometer
Published on: January 29, 2020
How Do Xanthophylls Protect Lipid Membranes from Oxidative Damage?
Renata Welc-Stanowska1,2, Rafal Pietras3, Bohun Mielecki3,4
1Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, 20-031 Lublin, Poland.
Abstract:
Here, we address the problem of the antioxidant activity of carotenoids in biomembranes. The activity of lutein and zeaxanthin in the quenching of singlet oxygen generated by photosensitization was monitored in lipid vesicles using a singlet oxygen-sensitive fluorescent probe and with the application of fluorescence lifetime imaging microscopy. The antioxidant activity of xanthophylls was interpreted on the basis of electron paramagnetic resonance oximetry results showing that xanthophylls constitute a barrier to the penetration of molecular oxygen into lipid membranes: to a greater extent in the 13-cis configuration than in all-trans. These results are discussed in relation to the trans-cis photoisomerization of xanthophylls observed in the human retina. It can be concluded that photoisomerization of xanthophylls is a regulatory mechanism that is important for both the modulation of light filtration through the macula and photoprotection by quenching singlet oxygen and creating a barrier to oxygen permeation to membranes.
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