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Related to Xanthophylls: chlorophyll b, Phycobilins



oxygen-containing carotenoids, the principal components of the yellow pigments in the leaves, flowers, fruits, and buds of higher plants, as well as in many algae and microorganisms. Xanthophylls are found less frequently in the animal world, for example, in the yolk of chicken eggs and in the liver and fatty tissue of mammals. These carotenoids are contained in the chloroplasts of the green parts of plants, in the chromoplasts of flowers and fruits, and in the lipophil sections of bacterial cells. Together with flavonoids, xanthophylls are responsible for the autumnal coloration of leaves.

The biological importance of xanthophylls is related to their ability to absorb sunlight from the short-wave range of the visible spectrum (380-520 nanometers). All photosynthetizing organs of green plants and of photosynthetic microorganisms contain xanthophylls. In these organs the absorbed light energy is transformed into chlorophyll or similar complexes. In this way, xanthophylls participate as auxiliary pigments in the photosynthetic process. Apparently, they also play the role of filters, protecting sensitive enzymes from destruction by light.

There are more than 50 known xanthophylls; they fall into various functional groups, including alcohols, ketones, aldehydes, acids, and simple and complex ethers. They belong to acyclic, monocyclic, and bicyclic carotenoids, containing 40 atoms of carbon. A typical representative is zeaxanthin (C40H56O2), the yellow crystals (melting point, 207–215°C), and its isomer—xanthophyl (lutein)—whose crystals are violet (melting point, 190–193°C). The biosynthesis of xanthophylls from colorless carotenoid hydrocarbons is catalyzed by atmospheric oxygen in sunlight.


Kretovich, V. L. Osnovy biokhimii rastenii, 5th ed. Moscow, 1971.


References in periodicals archive ?
The results found supplementation significantly improved the plasma antioxidant capacity, circulating macular xanthophyll levels, and the optical density of the macular pigment.
Some xanthophylls help phytoplankton absorb light, but others help them get rid of excess light.
Flavonoids are water soluble so enter into the mixed juice during processing while others such as chlorophylls, xanthophylls and carotenes are water insoluble hence removed in clarification.
Carotenoid found in cyanobacteria includes variety of xanthophylls and [beta] carotene.
Today these plants process phytosterols, carotenes, xanthophylls, specialty lipids and fatty acids from botanical, biological and marine sources.
Stresses of light harvesting system of higher light illumination light intensity involves major increased in xanthphyll--cycle dependent energy dissipation utilizes xanthophylls carotenoids in a presence of high light energy absorbed by chlorophyll is converted to heat and dissipated harmlessly , thus preventing the formation of singlet oxygen within the light harvesting complexes (Deoimming --Adams and Adms , 1996).
HMD: We are the world's first complete source for the entire range of macular xanthophylls for food fortification and dietary supplementation.
several students, depending on the size of the class, designated as chlorophylls a and b, and carotenes and xanthophylls in the antenna complex
By saponification the esters of xanthophylls were converted to free carotenoids and chlorophylls were also removed.