Information about Zeaxanthin
Zeaxanthin is one of the two 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 main difference between them is in the location of a double bond in one of the end rings. This difference gives lutein three chiral centers whereas zeaxanthin has two.
As a food additive, zeaxanthin is a food dye with E number E161h.
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.
There is also epidemiological evidence that increasing lutein and zeaxanthin intake lowers the risk of cataract development.
On September 10, 2007, in a 6-year study, researchers, led by John Paul SanGiovanni of the National Eye Institute, Maryland found that Lutein and zeaxanthin (nutrients in eggs, spinach and other green vegetables) protect against blindness (macular degeneration), affecting 1.2 million Americans, mostly after age 65. Lutein and zeaxanthin reduce the risk of AMD (journal Archives of Ophthalmology). Foods considered good sources of the nutrients also include kale, turnip greens, collard greens, romaine lettuce, broccoli, zucchini, corn, garden peas and Brussels sprouts.[1]
The retina is a thin layer of neural cells that lines the back of the eyeball of vertebrates and some cephalopods. It is comparable to the film in a camera.
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| Zeaxanthin | ||
|---|---|---|
| General | ||
| Systematic name | 4-[18-(4-hydroxy-2,6,6-trimethyl -1-cyclohexenyl)- 3,7,12,16-tetramethyl-octadeca- 1,3,5,7,9,11,13,15,17-nonaenyl]- 3,5,5-trimethyl-cyclohex-3-en-1-ol | |
| Other names | zeaxanthin; ß,ß-carotene-3,3'-diol | |
| Molecular formula | C40H56O2 | |
| SMILES | CC1CC(O)CC(C)(C)C=1C= CC(C)=CC=CC(C)=CC= CC=C(C)C=CC=C(C)C =CC2=C(C)CC(O)CC2(C)C | |
| Molar mass | 568.88 g/mol | |
| Appearance | orange-red | |
| CAS number | 144-68-3 | |
| PubChem | 91445 | |
| EINECS | 205-636-4 | |
| Properties | ||
| Density and phase | ? g/cm³, ? | |
| Solubility in water | insol. | |
| Melting point | 215.5 °C (488.7 K) | |
| Boiling point | ? °C (? K) | |
| Acidity (pKa) | ? | |
| Basicity (pKb) | ? | |
| Chiral rotation [α]D | ?° | |
| Viscosity | ? cP at ? °C | |
| Hazards | ||
| MSDS | External MSDS | |
| Main hazards | ? | |
| NFPA 704 | ||
| Flash point | ? °C | |
| R/S statement | R: ? S: ? | |
| RTECS number | ? | |
| Supplementary data page | ||
| Structure and properties | n, εr, etc. | |
| Thermodynamic data | Phase behaviour Solid, liquid, gas | |
| Spectral data | UV, IR, NMR, MS | |
| Related compounds | ||
| Other anions | ? | |
| Other cations | ? | |
| Related ? | ? | |
| Related compounds | lutein xanthophyll | |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) | ||
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 main difference between them is in the location of a double bond in one of the end rings. This difference gives lutein three chiral centers whereas zeaxanthin has two.
As a food additive, zeaxanthin is a food dye with E number E161h.
Isomers
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
There is epidemiological evidence of a relationship between low plasma concentrations of lutein and zeaxanthin on the one hand, and the risk of developing age-related macular degeneration (AMD) on the other. Some studies support the view that supplemental lutein and/or zeaxanthin help protect against AMD.There is also epidemiological evidence that increasing lutein and zeaxanthin intake lowers the risk of cataract development.
On September 10, 2007, in a 6-year study, researchers, led by John Paul SanGiovanni of the National Eye Institute, Maryland found that Lutein and zeaxanthin (nutrients in eggs, spinach and other green vegetables) protect against blindness (macular degeneration), affecting 1.2 million Americans, mostly after age 65. Lutein and zeaxanthin reduce the risk of AMD (journal Archives of Ophthalmology). Foods considered good sources of the nutrients also include kale, turnip greens, collard greens, romaine lettuce, broccoli, zucchini, corn, garden peas and Brussels sprouts.[1]
Natural occurrence
Zeaxanthin is one of the most common carotenoid alcohols found in nature. It is the pigment that gives 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.External links
References
| Major families of biochemicals | ||
| Peptides | Amino acids | Nucleic acids | Carbohydrates | Lipids | Terpenes | Carotenoids | Tetrapyrroles | Enzyme cofactors | Steroids | Flavonoids | Alkaloids | Polyketides | Glycosides | ||
| Analogues of nucleic acids: | Types of Carotenoids | Analogues of nucleic acids: |
| General: | ||
|---|---|---|
| Xanthophylls: | Astaxanthin | Canthaxanthin | Fucoxanthin | Lutein | Zeaxanthin | |
| Carotenes: | Lycopene | Carotene | |
Carotenoids are organic pigments that are naturally occurring in plants and some other photosynthetic organisms like algae, some types of fungus and some bacteria. There are over 600 known carotenoids; they are split into two classes, xanthophylls and carotenes.
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- For the moth genus, see Retina (moth).
The retina is a thin layer of neural cells that lines the back of the eyeball of vertebrates and some cephalopods. It is comparable to the film in a camera.
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Eyes are organs of vision that detect light. Different kinds of light-sensitive organs are found in a variety of organisms. The simplest eyes do nothing but detect whether the surroundings are light or dark, while more complex eyes can distinguish shapes and colors.
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IUPAC nomenclature is a system of naming chemical compounds and of describing the science of chemistry in general. It is developed and kept up to date under the auspices of the International Union of Pure and Applied Chemistry (IUPAC).
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A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. A chemical formula is also a short way of showing how a chemical reaction occurs.
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smiles
File extension:
Type of format: chemical file format
The simplified molecular input line entry specification or SMILES
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File extension:
.smiType of format: chemical file format
The simplified molecular input line entry specification or SMILES
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Molar mass, symbol M,[1] is the mass of one mole of a substance (chemical element or chemical compound).[2] It is a physical property which is characteristic of each pure substance.
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CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. They are also referred to as CAS numbers, CAS RNs or CAS #s.
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PubChem is a database of chemical molecules. The system is maintained by the National Center for Biotechnology Information (NCBI), a component of the National Library of Medicine, which is part of the United States National Institutes of Health (NIH).
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The EINECS number (for European Inventory of Existing Chemical Substances) is a registry number given to each chemical substance commercially available in the European Union between 1 January 1971 and 18 September 1981.
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In physics, density is mass m per unit volume V—how heavy something is compared to its size. A small, heavy object, such as a rock or a lump of lead, is denser than a lighter object of the same size or a larger object of the same weight, such as pieces of
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In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i.e. density, crystal structure, index of refraction, and so forth).
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Solubility is a physical property referring to the ability for a given substance, the solute, to dissolve in a solvent.[1] It is measured in terms of the maximum amount of solute dissolved in a solvent at equilibrium. The resulting solution is called a saturated solution.
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Water (H2O, HOH) is the most abundant molecule on Earth's surface, composing of about 70% of the Earth's surface as liquid and solid state in addition to being found in the atmosphere as a vapor.
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The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. Although the phrase would suggest a specific temperature and is commonly and incorrectly used as such in most textbooks and literature, most crystalline compounds
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boiling point of a liquid is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid.[1][2][3][4]
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An acid dissociation constant, denoted by Ka, is an equilibrium constant for the dissociation of a weak acid. According to the Brønsted-Lowry theory of acids and bases an acid is only recognised by its reaction with a base.
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An acid dissociation constant, denoted by Ka, is an equilibrium constant for the dissociation of a weak acid. According to the Brønsted-Lowry theory of acids and bases an acid is only recognised by its reaction with a base.
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The specific rotation of a chemical compound [α] is defined as the observed angle of optical rotation α when plane-polarized light is passed through a sample with a path length of 1 decimeter and a sample concentration of 1 gram per 1 deciliter.
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Viscosity is a measure of the resistance of a fluid to deform under either shear stress or extensional stress. It is commonly perceived as "thickness", or resistance to flow.
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The poise (symbol P; IPA: /pwɑːz/) is the unit of dynamic viscosity in the centimetre gram second system of units. It is named after Jean Louis Marie Poiseuille.
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material safety data sheet (MSDS) is a form containing data regarding the properties of a particular substance. An important component of product stewardship and workplace safety, it is intended to provide workers and emergency personnel with procedures for handling or
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Occupational safety and health (OSH) is a cross-disciplinary area concerned with protecting the safety, health and welfare of people engaged in work or employment. As a secondary effect, OSH may also protect co-workers, family members, employers, customers, suppliers, nearby
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NFPA 704 is a standard maintained by the U.S. National Fire Protection Association. It defines the colloquial "fire diamond" used by emergency personnel to quickly and easily identify the risks posed by nearby hazardous materials.
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The flash point of a flammable liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed.
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Risk and Safety Statements, also known as R/S statements, R/S numbers, R/S phrases, and R/S sentences, is a system of hazard codes and phrases for labeling dangerous chemicals and compounds.
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R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations.
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S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. The list was consolidated and republished in Directive 2001/59/EC , where translations into other EU languages may be found.
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The refractive index (or index of refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium. For example, typical glass has a refractive index of 1.
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The relative static permittivity (or static relative permittivity) of a material under given conditions is a measure of the extent to which it concentrates electrostatic lines of flux.
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