Astaxanthin

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Astaxanthin
Other names

3,3'-dihydroxy-ß-carotene-4,4'-dione; Astaxanthin (6CI); β-Carotene-4,4'-dione, 3,3'-dihydroxy-, all-trans- (8CI); (3S,3'S)-Astaxanthin; (3S,3'S)-Astaxanthin; (3S,3'S)-all-trans-Astaxanthin; (S,S)-Astaxanthin; Aquasta; AstaREAL; AstaXin; Astared; Astaxanthin, all-trans-; Astots 10O; Astots 5O; BioAstin; BioAstin oleoresin; Carophyll Pink; Lucantin Pink; NatuRose; Natupink; Ovoester; all-trans-Astaxanthin; trans-Astaxanthin [1]
Identifiers
CAS number 472-61-7 YesY
PubChem 5281224
ChemSpider 4444636 YesY
UNII 8XPW32PR7I YesY
ChEMBL CHEMBL445751 N
Jmol-3D images Image 1
Properties
Molecular formula C40H52O4
Molar mass 596.84 g mol−1
Appearance red solid powder
Density 1.071 g/mL [2]
Melting point

216 degrees Celsius [2]
Boiling point

774 degrees Celsius [2]
Solubility in water 30 g/L in DCM; 10 g/L in CHCl3; 0.5 g/L in DMSO; 0.2 g/L in acetone [3]
 N (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Astaxanthin (pronounced /æstəˈzænθɨn/) is a carotenoid. It belongs to a larger class of phytochemicals known as terpenes, which are built from five carbon precursors; isopentenyl diphosphate (or IPP) and dimethylallyl diphosphate (or DMAPP). Astaxanthin is classified as a xanthophyll (originally derived from a word meaning "yellow leaves" since yellow plant leaf pigments were the first recognized of the xanthophyll family of carotenoids), but currently employed to described carotenoid compounds that have oxygen containing moities, hydroxyl (OH) or ketone (=0), such as zeaxanthin and canthaxanthin. Indeed, astaxanthin is a metabolite of zeaxanthin and/or canthaxanthin, containing both hydroxyl and ketone functional groups. Like many carotenoids, astaxanthin is a colorful, lipid-soluble pigment. This colour is due to the extended chain of conjugated (alternating double and single) double bonds at the centre of the compound. This chain of conjugated double bonds is also responsible for the antioxidant function of astaxanthin, as well as other carotenoids, as this results in a region of decentralized electrons, that can be donated to quench the charge of a reactive molecule.

Astaxanthin is found in microalgae, yeast, salmon, trout, krill, shrimp, crayfish, crustaceans, and the feathers of some birds. It provides the red color of salmon meat and the red color of cooked shellfish. [4][5] Professor Basil Weedon was the first to map the structure of astaxanthin.

Astaxanthin, unlike several carotenes and one other known carotenoid, is not converted to vitamin A (retinol) in the human body. Like other carotenoids, astaxanthin has self-limited absorption orally and such low toxicity by mouth that no toxic syndrome is known. It is an antioxidant with a slightly lower antioxidant activity in some model systems than other carotenoids. However, in living organisms the free-radical terminating effectiveness of each carotenoid is heavily modified by its lipid solubility, and thus varies with the type of system being protected. [6]

While astaxanthin is a natural nutritional component, it can also be used as a food supplement. The supplement is intended for human, animal, and aquaculture consumption. The commercial production of astaxanthin comes from both natural and synthetic sources.

The U.S. Food and Drug Administration (FDA) has approved astaxanthin as a food coloring (or color additive) for specific uses in animal and fish foods.[7] The European Commission considers it food dye and it is given the E number E161j.[8] Natural astaxanthin is considered generally recognized as safe (GRAS) by the FDA,[9][10] but as a food coloring in the United States it is restricted to use in animal food.[11]

Contents

[edit] Natural sources

The following sources are used for the commercial production of astaxanthin:

Pandalus borealis (Arctic shrimp)

As a natural source, the following can be found in nature (or a production facility) with the approximate astaxanthin concentrations:

Source Astaxanthin concentration (ppm)[12]
Salmonids ~ 5
Plankton ~ 60
Krill ~ 120
Arctic shrimp (P borealis) ~ 1,200
Phaffia yeast ~ 10,000
Haematococcus pluvialis ~ 40,000

Currently, the primary natural source for astaxanthin is the microalgae Haematococcus pluvialis.[13] It seems to accumulate the highest levels of astaxanthin in nature;[14] Commercially more than 40 g of astaxanthin can be obtained from one kg of dry biomass.[15] It has the advantage of the population doubling every week, which means scaling up is not an issue. However, it does require some expertise to grow the algae with a high astaxanthin content. Specifically, the microalgae is grown in two phases. First, in the green phase, the cells are given an abundance of nutrients to promote proliferation of the cells. In the subsequent red phase, the cells are deprived of nutrients and subjected to intense sunlight to induce encystment (carotogenesis), during which the cells produce high levels of astaxanthin as a protective mechanism against the environmental stress. The cells, with their high concentrations of astaxanthin, are then harvested.[16]

Phaffia yeast Xanthophyllomyces dendrorhous exhibits 100% free, non-esterified astaxanthin, which is considered advantageous because it is readily absorbable and need not be hydrolysed in the digestive tract of the fish. In contrast to synthetic and bacteria sources of astaxanthin, yeast sources of astaxanthin consist virtually all in 3R, 3’R form, an important astaxanthin source in nature. Finally, the geometrical isomer, all-E, is higher in yeast sources of astaxanthin, as compared to synthetic sources. This contributes to greater efficacy because the all-E (trans) isomer has greater bio-availability than the cis isomer.[17]

For obtaining astaxanthin from Euphausia superba (Antarctic krill), there are a number of issues:[18]

Krill
The Krill fishing operation is complex. It is done in Antarctic waters, under extreme weather conditions and far away from ports with substantial operational complexities. Krill's fishing location and the difficult weather conditions in the main fishing area, together with the costs involved in the operation, have contributed to a slow development of the industry. Krill fishing is by far different than any other fishing operation today known. The knowledge to work with it belongs to very few people in the world.

Astaxanthin is commercially collected from shrimp processing waste. 12,000 pounds of wet shrimp shells can yield a 6-8 gallon astaxanthin/triglyceride oil mixture.[19]

[edit] Synthetic sources

Nearly all commercial astaxanthin for aquaculture is produced synthetically, with an annual turnover of over $200 million and a selling price of ~$2000 per kilo.[15] However, synthetic production of astaxanthin is not preferred in some cases because synthetic astaxanthin contains a mixture of stereoisomers. Astaxanthin is fairly abundant and obtainable from natural sources, and some consumers prefer natural products over synthetic ones.[16] Synthetic astaxanthin fetches $2000 per kg, while the natural product is sold for over $7000 per kg.[20]

An efficient synthesis from isophorone, cis-3-methyl-2-penten-4-yn-1-ol and a symmetrical C10-dialdehyde has been discovered and is used commercially. It combines these chemicals together with an ethynylation and then a Wittig reaction.[21] Two equivalents of the proper ylide combined with the proper dialdehyde in a solvent of methanol, ethanol, or a mixture of the two, yields astaxanthin in up to 88% yields.[22]

[edit] Metabolic engineering

The cost of astaxanthin production, high commercial price and lack of a leading fermentation production systems, combined with the short falls of chemical synthesis mean that research into alternative fermentation production methods has been carried out. Metabolic engineering offers the opportunity to create biological systems for the production of a specifici target compound. The metabolic engineering of bacteria (Escherichia coli) recently allowed production of astaxanthin at >90% of the total carotenoids, providing the first engineered production system capable of efficient astaxanthin production.[23]

[edit] Difference between natural and synthetic forms

Astaxanthin has two chiral centers, at the 3- and 3′-positions. Therefore, there are three stereoisomers; (3R,3′R), (3R,3′S) (meso), and (3S,3′S). Synthetic astaxanthin contains a mixture of the three, in approximately 1:2:1 proportions. Naturally occurring astaxanthin varies considerably from one organism to another. The astaxanthin in fish is of whatever stereoisomer the fish ingested.[24] The astaxanthin produced by haematococcus pluvialis, which is commonly used in the feed of animals that are in turn consumed by humans, is the (3S,3′S) stereoisomer.[16]

[edit] Uses

Astaxanthin is used as a feed supplement for salmon, crabs, shrimp, chickens and egg production.[25] Regardless of the source, astaxanthin provides some important benefits beyond coloration. It also has been found to be essential for proper growth and survival.[15]

[edit] For seafood and animals

The primary use of synthetic astaxanthin today is as an animal feed additive to impart coloration, including farm-raised salmon and egg yolks.[15] Synthetic carotenoid pigments colored yellow, red or orange represent about 15–25% of the cost of production of commercial salmon feed.[26] Today, almost all commercial astaxanthin for aquaculture is produced synthetically from petrochemical sources. While it constitutes a tiny portion of salmon feed (50 to 100 parts per million), astaxanthin represents a major share of the cost, up to 20 percent.[27]

[edit] The farm-raised salmon lawsuit

Class action lawsuits have been filed against some major grocery store chains for not clearly labeling the salmon "color added".[27] The chains followed up quickly by labeling all such salmon as "color added". "...Smith & Lowney persisted with the suit for damages, but a Seattle judge dismissed [the case], ruling that enforcement of the applicable food laws was up to government and not individuals."[28]

[edit] For humans

The primary use for humans is as a food supplement. Research shows that, due to astaxanthin's potent antioxidant activity, it may be beneficial in cardiovascular, immune, inflammatory and neurodegenerative diseases.[29] While it does function as a carotenoid antioxidant, research has shown that lycopenes are more efficient antioxidants than carotenoids.[6] Some research has suggested potential as an anti-cancer agent.[30] Some research supports the assumption that it may protect body tissues from oxidative damage.[31]

[edit] Role in the food chain

It has been speculated that gulls are "flushed" pink when molting, especially in areas with farm-raised salmon.[32] However, not enough is known about the relationship between astaxanthin and plumage.[33] For example, cardinals seem to produce astaxanthin from carotenoids when molting, even when fed primarily seed with natural yellow dye.[34]

Lobsters, shrimp, and some crabs turn red when cooked because the astaxanthin, which was bound to the protein in the shell, becomes free as the protein denatures and unwinds. The freed pigment is thus available to absorb light and produce the red color. [35]

[edit] Regulations

In April 2009, the US FDA approved astaxanthin as an additive for fish feed only as a component of a stabilized color additive mixture. Color additive mixtures for fish feed made with astaxanthin may contain only those diluents that are suitable.[7] The color additives astaxanthin, ultramarine blue, canthaxanthin, synthetic iron oxide, dried algae meal, Tagetes meal and extract, and corn endosperm oil are approved for specific uses in animal foods.[36] Haematococcus algae meal (21 CFR 73.185) and Phaffia yeast (21 CFR 73.355) for use in fish feed to color salmonoids were added in 2000.[37][38][39] In the European Union, astaxanthin-containing food supplements derived from sources that have no history of use as a source of food in Europe, fall under the remit of the Novel Food legislation, EC (No.) 258/97. Since 1997, there have been five novel food applications concerning products that contain astaxanthin extracted from these novel sources. In each case, these applications have been simplified or substantial equivalence applications, because astaxanthin itself is recognised as a food component in the EU diet.[40][41][42][43]

[edit] References

  1. ^ SciFinder Web (accessed Sep 28, 2010). Astaxanthin (472-61-7) Name
  2. ^ a b c SciFinder Web (accessed Sep 28, 2010). Astaxanthin (472-61-7) Experimental Properties.
  3. ^ Hussein G, Goto H, Oda S, Sankawa U, Matsumoto K, Watanabe H (April 2006). "Antihypertensive potential and mechanism of action of astaxanthin: III. Antioxidant and histopathological effects in spontaneously hypertensive rats". Biol. Pharm. Bull. 29 (4): 684–8. PMID 16595899. http://joi.jlc.jst.go.jp/JST.JSTAGE/bpb/29.684?from=PubMed. 
  4. ^ Carotenoid Introductory
  5. ^ Carotenoid — See: Astaxanthin
  6. ^ a b Mortensen, A.; Skibsted, L. H. (1997). "Importance of carotenoid structure in radical scavenging reactions". J. Agric. Food Chem. 45 (8): 2970−7. doi:10.1021/jf970010s. http://pubs.acs.org/doi/abs/10.1021/jf970010s. 
  7. ^ a b "Summary of Color Additives for Use in United States in Foods, Drugs, Cosmetics, and Medical Devices". http://www.fda.gov/ForIndustry/ColorAdditives/ColorAdditiveInventories/ucm115641.htm.  See Note 1.
  8. ^ — Currently unlisted. Will look for a better ref.
  9. ^ Astaxanthin wins full GRAS status
  10. ^ Algatechnologies gets GRAS for AstaPure astaxanthin
  11. ^ Summary of Color Additives for Use in United States in Foods, Drugs, Cosmetics, and Medical Devices
  12. ^ http://algatech.com/astax.htm
  13. ^ Haematococcus pluvialis
  14. ^ astafactor.com Algae
  15. ^ a b c d astafactor.com Astax
  16. ^ a b c Boussiba; Sammy, V.; Avigad, C.; et al. (2000) Procedure for large-scale production of astaxanthin from haematococcus. U. S. Patent 6,022,701.
  17. ^ Astaxanthin Source Comparison
  18. ^ aquafeed.com
  19. ^ Anderson, Lyle K. Extraction of Carotenoid Pigment from Shrimp Processing Waste. U.S. Patent 3906112. Sep 16, 1975
  20. ^ Leora Eren Frucht; Sharon Kanon (8 May 2005). "Israel grows red algae in the desert to fight disease". http://www.israel21c.org/index.php?option=com_content&view=article&id=1068:israel-grows-red-algae-in-the-desert-to-fight-disease&catid=58:environment&Itemid=101. Retrieved 14 Oct 2009. 
  21. ^ Ashford's Dictionary of Industrial Chemicals, 3rd Edition, 2011, page 984
  22. ^ Krause, Wolfgang; Henrich, Klaus; Paust, Joachim; et al. Preaparation of Astaxanthin. DE 19509955.9 Mar. 18, 1995
  23. ^ Scaife, M. A.; Burja, A. M.; Wright, P. C. (2009). "Characterization of cyanobacterial β-carotene ketolase and hydroxylase genes inEscherichia coli, and their application for astaxanthin biosynthesis". Biotechnology and Bioengineering 103 (5): 944–955. doi:10.1002/bit.22330. PMID 19365869.  edit
  24. ^ US application 20050014824  (online here) (also EP 1442083 )
  25. ^ — just the egg part
  26. ^ Fisheries and Oceans Canada — Aquaculture Issues
  27. ^ a b "Smith & Lowney — Farm-raised Salmon Coloring". 2003. http://www.smithandlowney.com/salmon/. Retrieved 14 Oct 2009. 
  28. ^ "Pigments in Salmon Aquaculture: How to Grow a Salmon-colored Salmon". Archived from the original on 13 Oct 2007. http://web.archive.org/web/20071013221146/http://seafoodmonitor.com/sample/salmon.html. Retrieved 18 July 2009. 
  29. ^ Fassett, Robert G.; Coombes, Jeff S. (2009). "Astaxanthin, oxidative stress, inflammation and cardiovascular disease". Future Cardiology 4 (3): 333–342. 
  30. ^ Palozza, P.; Torelli, C.; Boninsegna, A.; Simone, R.; Catalano, A.; Mele, M. C.; Picci, N. (2009). "Growth-inhibitory effects of the astaxanthin-rich alga Haematococcus pluvialis in human colon cancer cells". Cancer Lett 283 (1): 108–117. doi:10.1016/j.canlet.2009.03.031. PMID 19423215. 
  31. ^ Guerin M, Huntley ME, Olaizola M (May 2003). "Haematococcus astaxanthin: applications for human health and nutrition". Trends Biotechnol. 21 (5): 210–6. doi:10.1016/S0167-7799(03)00078-7. PMID 12727382. http://linkinghub.elsevier.com/retrieve/pii/S0167779903000787.  as PDF
  32. ^ McGraw, Kevin; Hardy, Lisa (2006) (pdf). Astaxanthin is responsible for the pink plumage flush in Franklin's and Ring-billed gulls. Tempe, AZ: School of Life Sciences, Arizona State University. pp. 5. http://www.public.asu.edu/~kjmcgraw/pubs/JFO2006.pdf. 
  33. ^ "Notes on the effects of Astaxanthin on the plumage of birds". 2006. http://www.didgood.com/recipes/information/salmon/astaxanthin/research-Bird-Plumage/pdf.html. Retrieved 19 July 2009. 
  34. ^ http://www.colorado.edu/chemistry/chem5181/HP_GCMS_Paper2.pdf
  35. ^ http://www.ochef.com/718.htm
  36. ^ See 21 CFR 73.35,73.50, 73.75, 73.200, 73.275, 73.295, 73.315, respectively.
  37. ^ Code of Federal Regulations Title 21 §73.35 FDA decision on Astaxanthin
  38. ^ http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=73.185 Code of Federal Regulations Title 21 §73.185 FDA decision on Haematococcus algae meal
  39. ^ Food Additive Status List 2009
  40. ^ UK novel food application
  41. ^ UK novel food application
  42. ^ UK novel food application
  43. ^ UK novel food application

[edit] External links
Carotenes (C40)
Xanthophylls (C40)
Apocarotenoids (C<40)
Vitamin A retinoids (C20)
Retinoid drugs
Retrieved from "http://en.wikipedia.org/w/index.php?title=Astaxanthin&oldid=475847263"
Personal tools
Namespaces
Variants
Actions
Navigation
Interaction
Toolbox
Print/export
Languages