Xanthophylls (originally phylloxanthins) are yellow pigments from the carotenoid group. Their molecular structure is based on carotenes; contrary to the carotenes, some hydrogen atoms are substituted by hydroxyl groups and/or some pairs of hydrogen atoms are substituted by oxygen atoms. They are found in the leaves of most plants and are synthesized within the plastids. They are involved in photosynthesis along with green chlorophyll, which typically covers up the yellow except in autumn, when the chlorophyll is denatured by the cold.

In plants, xanthophylls are considered accessory pigments, along with anthocyanins, carotenes, and sometimes phycobiliproteins. Xanthophylls, along with carotenic pigments are seen when leaves turn orange in the autumn season.

Animals cannot produce xanthophylls, and thus xanthophylls found in animals (e.g. in the eye) come from their food intake. The yellow color of chicken egg yolks also comes from ingested xanthophylls.

Xanthophylls are oxidized derivatives of carotenes. They contain hydroxyl groups and are more polar than carotenes; therefore, carotenes travel further than xanthophylls in paper chromatography.

The group of xanthophylls includes lutein, zeaxanthin, neoxanthin, violaxanthin, and α- and β-cryptoxanthin.

Xanthophyll has a chemical formula of C40H56O2.

Xanthophyll cycle

The xanthophyll cycle involves conversions of pigments from a non-energy-quenching form to energy-quenching forms. This is a way to reduce the absorption cross-section of the light harvesting antenna, and thus to reduce the amount of energy that reaches the photosynthetic reaction centers. Reducing the light harvesting antenna is one of the main ways of protecting against photoinhibition and changes in the xanthophyll cycling takes place on a time scale of minutes to hours. [Falkowski, P. G. & J. A. Raven, 1997, Aquatic photosynthesis. Blackwell Science, 375 pp] In higher plants there are three carotenoid pigments that are active in the xanthophyll cycle: violaxanthin, antheraxanthin and zeaxanthin. During light stress violoxanthin is converted to antheraxanthin and zeaxanthin, which functions as photoprotective pigments. This conversion is done by the enzyme violaxanthin de-epoxidase. [Taiz, Lincoln and Eduardo Zeiger. 2006. "Plant Physiology". Sunderland, MA: Sinauer Associates, Inc. Publishers, Fourth edition, 764 pp]

In diatoms and dinoflagellates the xanthophyll cycle consists of the pigment diadinoxanthin, which is transformed into diatoxanthin (diatoms) or dinoxanthin (dinoflagellates), at high light. [Jeffrey, S. W. & M. Vesk, 1997. Introduction to marine phytoplankton and their pigment signatures. In Jeffrey, S. W., R. F. C. Mantoura & S. W. Wright (eds.), Phytoplankton pigments in oceanography, pp 37-84. – UNESCO Publishing, Paris.]


*Demmig-Adams, B & W. W. Adams, 2006. Photoprotection in an ecological context: the remarkable complexity of thermal energy dissipation, New Phytologist, 172: 11–21.

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Look at other dictionaries:

  • Xanthophyll — Xan tho*phyll, n. [Xantho + Gr. fy llon leaf.] (Bot.) A yellow coloring matter found in yellow autumn leaves, and also produced artificially from chlorophyll; formerly called also {phylloxanthin}. [1913 Webster] …   The Collaborative International Dictionary of English

  • Xanthophyll — Xanthophyll, s. Chlorophyll …   Meyers Großes Konversations-Lexikon

  • xanthophyll — [zan′thə fil] n. [ XANTHO + PHYLL] a yellow, crystalline pigment, C40H56O2, found in plants; lutein: it is related to carotene and is the basis of the yellow seen in autumn leaves xanthophyllous [zan΄fil′əs] adj …   English World dictionary

  • xanthophyll — Oxygenated derivative of carotene; a yellow plant pigment, occurring also in egg yolk and corpus luteum. SYN: lutein (2), luteol, luteole. * * * xan·tho·phyll zan thə .fil n any of several neutral yellow to orange carotenoid pigments that are… …   Medical dictionary

  • xanthophyll — n. a yellow pigment found in green leaves. An example of a xanthophyll is lutein …   The new mediacal dictionary

  • xanthophyll — ksantofilas statusas T sritis ekologija ir aplinkotyra apibrėžtis Karotinoidų grupės pigmentas, kurio molekulėje yra deguonies. Yra augalų lapuose, žieduose, vaisiuose, pumpuruose, mikroorganizmuose, dumbliuose, kiaušinio trynyje, kepenyse,… …   Ekologijos terminų aiškinamasis žodynas

  • xanthophyll — noun Etymology: French xanthophylle, from xanth + phylle phyll Date: 1838 any of several yellow to orange carotenoid pigments that are oxygen derivatives of carotenes; especially lutein …   New Collegiate Dictionary

  • Xanthophyll — Strukturen einiger Xanthophylle Astaxanthin (CAS 472 61 7) Canthaxanthin (CAS 514 78 3) …   Deutsch Wikipedia

  • xanthophyll — n. [Gr. xanthos, yellow; phyllon, leaf] An oxidised derivative of carotene found in the blood of some plant eating insects …   Dictionary of invertebrate zoology

  • xanthophyll — xanthophyllous, adj. /zan theuh fil/, n. Biochem. lutein (def. 1). Also, xanthophyl. [1830 40; < F xanthophylle. See XANTHO , PHYLL] * * * …   Universalium

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