Macular pigments lutein and zeaxanthin as blue light filters studied in liposomes

Arch Biochem Biophys. 2001 Jul 15;391(2):160-4. doi: 10.1006/abbi.2001.2411.


Lutein and zeaxanthin are the predominant carotenoids in the human macula lutea. Epidemiological data suggest that an increased intake of a lutein-rich diet correlates with a diminished risk for age-related macular degeneration, a major cause of impaired vision in the elderly. Filtering of blue light has been proposed as a possible mechanism of protection. Here, the blue light filter efficacy of carotenoids was investigated in unilamellar liposomes loaded in the hydrophilic core space with a fluorescent dye, Lucifer yellow, excitable by blue light. Carotenoids were incorporated into the lipophilic membrane. Fluorescence emission in carotenoid-containing liposomes was lower than in carotenoid-free controls when exposed to blue light, indicating a filter effect. Filter efficacy was in the order lutein > zeaxanthin > beta-carotene > lycopene. Some of the difference in blue light filter efficacy of carotenoids is attributable to differences in extinction coefficients, and a major further contribution is suggested to be related to the orientation of the incorporated molecules in the liposomal membrane.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Filtration
  • Humans
  • Light
  • Liposomes / metabolism*
  • Lutein / metabolism*
  • Macula Lutea / metabolism*
  • Macula Lutea / radiation effects
  • Spectrum Analysis
  • Xanthophylls
  • Zeaxanthins
  • beta Carotene / analogs & derivatives
  • beta Carotene / metabolism*


  • Liposomes
  • Xanthophylls
  • Zeaxanthins
  • beta Carotene
  • Lutein