Zeaxanthin Identifiers CAS number PubChem ChemSpider UNII ChEBI Jmol-3D images Image 1 Properties Molecular formula C40H56O2 Molar mass 568.88 g/mol Appearance orange-red Melting point
215.5 °C, 489 K, 420 °F
Solubility in water insol. Related compounds Related compounds lutein
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Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Zeaxanthin is one of the most common carotenoid alcohols found in nature. It is important in the xanthophyll cycle. Synthesized in plants & some micro-organisms, it is the pigment that gives paprika (made from bell peppers), corn, saffron, and many other plants & microbes their characteristic color.
The name (pronounced zee-uh-zan'-thin) is derived from Zea mays (common yellow maize corn) in which zeaxanthin provides the primary yellow pigment, plus the Greek word for yellow (see xanthophyll).
Xanthophylls such as zeaxhanthin are found in highest quantity in the leaves of most green plants, where they act to modulate light energy and perhaps serve as a non-photochemical quenching agent to deal with triplet chlorophyll (an excited form of chlorophyll), which is overproduced at very high light levels, during photosynthesis.
Animals derive zeaxanthin from a plant diet. Zeaxanthin is one of the two primary xanthophyll carotenoids contained within the retina of the eye. Within the central macula, zeaxanthin is the dominant component, whereas in the peripheral retina, lutein predominates.
Lutein and zeaxanthin have identical chemical formulas and are isomers, but they are not stereoisomers. The only difference between them is in the location of the double bond in one of the end rings. This difference gives lutein three chiral centers whereas zeaxanthin has two. Because of symmetry, the (3R,3'S) and (3S,3'R) stereoisomers of zeaxanthin are identical. Therefore, zeaxanthin has only three stereoisomeric forms. The (3R,3'S) stereoisomer is called meso-zeaxanthin.
The principal natural form of zeaxanthin is (3R,3'R)-zeaxanthin. The macula mainly contains the (3R,3'R)- and meso-zeaxanthin forms, but it also contains much smaller amounts of the third (3S,3'S) form.
Relationship with diseases of the eye
Several observational studies have connected high dietary intake of foods providing zeaxanthin with lower incidence of age-related macular degeneration (AMD), most notably the Age-Related Eye Disease study (AREDS). There is currently insufficient evidence to assess the effectiveness of dietary or supplemental antioxidants in treatment or primary prevention of ARMD, or the formation or progression of cataracts. Any benefit is more likely to be apparent in subpopulations of individuals exposed to high oxidative stress, such as heavy smokers or those with poor nutrition. In 2005, the US Food and Drug Administration rejected a Qualified Health Claims application by Xangold, citing insufficient evidence supporting the use of a zeaxanthin-containing supplement in prevention of AMD.
Zeaxanthin is one of the most common carotenoid alcohols found in nature. It is the pigment that gives paprika (made from bell peppers), corn, saffron, and many other plants their characteristic color. Zeaxanthin breaks down to form picrocrocin and safranal, which are responsible for the taste and aroma of saffron.
Foods considered good sources of lutein and zeaxanthin include eggs, spinach, goji berry, kale, turnip greens, collard greens, romaine lettuce, broccoli, zucchini, kiwifruit, corn, garden peas, swiss chard and Brussels sprouts.
- ^ See POLA Study
- ^ a b Krishnadev N, Meleth AD, Chew EY (May 2010). "Nutritional supplements for age-related macular degeneration". Current Opinion in Ophthalmology 21 (3): 184–9. doi:10.1097/ICU.0b013e32833866ee. PMC 2909501. PMID 20216418. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2909501.
- ^ a b SanGiovanni JP, Chew EY, Clemons TE, et al. (September 2007). "The relationship of dietary carotenoid and vitamin A, E, and C intake with age-related macular degeneration in a case-control study: AREDS Report No. 22". Archives of Ophthalmology 125 (9): 1225–32. doi:10.1001/archopht.125.9.1225. PMID 17846363.
- ^ Chong EW, Wong TY, Kreis AJ, Simpson JA, Guymer RH (October 2007). "Dietary antioxidants and primary prevention of age related macular degeneration: systematic review and meta-analysis". BMJ (Clinical Research Ed.) 335 (7623): 755. doi:10.1136/bmj.39350.500428.47. PMC 2018774. PMID 17923720. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2018774.
- ^ Fernandez MM, Afshari NA (January 2008). "Nutrition and the prevention of cataracts". Current Opinion in Ophthalmology 19 (1): 66–70. doi:10.1097/ICU.0b013e3282f2d7b6. PMID 18090901.
- ^ US FDA, Qualified Health Claims: Letter of Denial - Xangold Lutein Esters, Lutein, or Zeaxanthin and Reduced Risk of Age-related Macular Degeneration or Cataract Formation (Docket No. 2004Q-0180)
- ^ Spice Science and Technology, K. Hirasa, M. Takamasa, page 15
Carotenes (C40) Xanthophylls (C40) Apocarotenoids (C<40) Vitamin A retinoids (C20) Retinoid drugs
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Look at other dictionaries:
Zeaxanthin — ⇒ Xanthophylle … Deutsch wörterbuch der biologie
Zeaxanthin — Strukturformel Allgemeines Name Zeaxanthin Andere Namen … Deutsch Wikipedia
Zeaxanthin — Ze|a|xan|thin [↑ Zea u. ↑ xanthin], das; s; Syn.: β, β Carotin 3,3′ diol: im Pflanzen u. Tierreich verbreitetes, als Lebensmittelfarbstoff einsetzbares orangegelbes Carotinoid. * * * Zeaxanthin [zu Zea und griechisch xanthós »gelb«] das, s,… … Universal-Lexikon
zeaxanthin — noun Etymology: International Scientific Vocabulary zea (from New Latin Zea) + xanthin carotenoid pigment, from xanth + 1 in Date: 1929 an isomer of lutein occurring especially in fruits and vegetables (as spinach and corn) … New Collegiate Dictionary
zeaxanthin — noun A yellow crystalline carotenoid alcohol that occurs widely with lutein, with which it is isomeric, and is the chief pigment of maize. Syn: E161h, food colouring … Wiktionary
zeaxanthin — A carotene found in corn, fruits, seeds, and egg yolk; isomeric with xanthophyll. SYN: zeaxanthol. [Mod. L. Zea, Indian corn, fr. L. zea, grain + G. xanthos, yellow, + in] * * * ze·a·xan·thin .zē ə zan thən n a yellow cry … Medical dictionary
Zeaxanthin — Ze|a|xan|thin 〈n.; Gen.: s; Pl.: unz.; Biochemie〉 gelber Farbstoff des Maiskorns [Etym.: <Zea + Xanthin] … Lexikalische Deutsches Wörterbuch
Zeaxanthin — Ze|a|xan|thin das; s: im Maiskorn u. anderen Früchten enthaltenes ↑Xanthophyll … Das große Fremdwörterbuch
zeaxanthin — ze·a·xanthin … English syllables
zeaxanthin — noun yellow carotenoid (isomeric with lutein and occurs widely with it) that is the main pigment in yellow Indian corn • Hypernyms: ↑carotenoid … Useful english dictionary