| Astaxanthin is a keto-carotenoid within a group of chemical compounds known as carotenoids or terpenes. Astaxanthin is a metabolite of zeaxanthin and canthaxanthin, containing both hydroxyl and ketone functional groups.
It is a lipid-soluble pigment with red coloring properties, which result from the extended chain of conjugated (alternating double and single) double bonds at the center of the compound. The presence of the hydroxyl functional groups and the hydrophobic hydrocarbons render the molecule amphiphilic.
Astaxanthin is produced naturally in the freshwater microalgae Haematococcus pluvialis, the yeast fungus Xanthophyllomyces dendrorhous (also known as Phaffia rhodozyma) and the bacteria Paracoccus carotinifaciens. When the algae are stressed by lack of nutrients, increased salinity, or excessive sunshine, they create astaxanthin. Animals who feed on the algae, such as salmon, red trout, red sea bream, flamingos, and crustaceans (shrimp, krill, crab, lobster, and crayfish), subsequently reflect the red-orange astaxanthin pigmentation.
Astaxanthin is used as a dietary supplement for human, animal, and aquaculture consumption. Astaxanthin from algae, synthetic and bacterial sources is generally recognized as safe in the United States. The US Food and Drug Administration has approved astaxanthin as a food coloring (or color additive) for specific uses in animal and fish foods. The European Commission considers it as a food dye with E number E161j. The European Food Safety Authority has set an Acceptable Daily Intake of 0.2 mg per kg body weight, as of 2019. As a food color additive, astaxanthin and astaxanthin dimethyldisuccinate are restricted for use in Salmonid fish feed only.
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InChI=1S/C40H52O4/c1- 27(17-13-19-29(3)21-23-33-31(5)37(43)35(41)25-39(33,7)8)15-11-12-16-28(2)18-14-20-30(4)22-24-34-32(6)38(44)36(42)26-40(34,9)10/h11-24,35-36,41-42H,25-26H2,1-10H3/b12-11+,17-13+,18-14+,23-21+,24-22+,27-15+,28-16+,29-19+,30-20+/t35-,36-/m0/s1 |
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| CC(\C=C\C=C(C)\C=C\C1=C(C)C(=O)[C@@H](O)CC1(C)C)=C/C=C/C=C(C)/C=C/C=C(C)/C=C/C1=C(C)C(=O)[C@@H](O)CC1(C)C |
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antioxidant
A substance that opposes oxidation or inhibits reactions brought about by dioxygen or peroxides.
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animal metabolite
Any eukaryotic metabolite produced during a metabolic reaction in animals that include diverse creatures from sponges, insects to mammals.
food colouring
A food additive that imparts colour to food. In European countries, E-numbers for permitted food colours are from E 100 to E 199, divided into yellows (E 100-109), oranges (E 110-119), reds (E 120-129), blues and violets (E 130-139), greens (E 140-149), browns and blacks (E 150-159), and others (E 160-199).
plant metabolite
Any eukaryotic metabolite produced during a metabolic reaction in plants, the kingdom that include flowering plants, conifers and other gymnosperms.
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anticoagulant
An agent that prevents blood clotting.
food colouring
A food additive that imparts colour to food. In European countries, E-numbers for permitted food colours are from E 100 to E 199, divided into yellows (E 100-109), oranges (E 110-119), reds (E 120-129), blues and violets (E 130-139), greens (E 140-149), browns and blacks (E 150-159), and others (E 160-199).
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View more via ChEBI Ontology
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(3S,3'S)-3,3'-dihydroxy-β,β-carotene-4,4'-dione
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(3S,3'S)-astaxanthin
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ChemIDplus
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3,3'-dihydroxy-β,β-carotene-4,4'-dione
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ChemIDplus
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3,3'-dihydroxy-β-carotene-4,4'-dione
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ChemIDplus
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all-trans-(3S,3'S)-astaxanthin
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ChemIDplus
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all-trans-(3S,3'S)-astaxanthin
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UniProt
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ASTAXANTHIN
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PDBeChem
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Astaxanthin
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KEGG COMPOUND
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astaxanthine
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ChemIDplus
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E 161j
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ChEBI
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ovoester
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ChemIDplus
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1917937
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Beilstein Registry Number
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Beilstein
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1917937
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Reaxys Registry Number
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Reaxys
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472-61-7
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CAS Registry Number
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KEGG COMPOUND
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472-61-7
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CAS Registry Number
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ChemIDplus
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Tominaga K, Hongo N, Karato M, Yamashita E (2012)
Cosmetic benefits of astaxanthin on humans subjects.
Acta biochimica Polonica 59, 43-47 [PubMed:22428137]
[show Abstract]
Two human clinical studies were performed. One was an open-label non-controlled study involving 30 healthy female subjects for 8 weeks. Significant improvements were observed by combining 6 mg per day oral supplementation and 2 ml (78.9 μM solution) per day topical application of astaxanthin. Astaxanthin derived from the microalgae, Haematococcus pluvialis showed improvements in skin wrinkle (crow's feet at week-8), age spot size (cheek at week-8), elasticity (crow's feet at week-8), skin texture (cheek at week-4), moisture content of corneocyte layer (cheek in 10 dry skin subjects at week-8) and corneocyte condition (cheek at week-8). It may suggest that astaxanthin derived from H. pluvialis can improve skin condition in all layers such as corneocyte layer, epidermis, basal layer and dermis by combining oral supplementation and topical treatment. Another was a randomized double-blind placebo controlled study involving 36 healthy male subjects for 6 weeks. Crow's feet wrinkle and elasticity; and transepidermal water loss (TEWL) were improved after 6 mg of astaxanthin (the same as former study) daily supplementation. Moisture content and sebum oil level at the cheek zone showed strong tendencies for improvement. These results suggest that astaxanthin derived from Haematococcus pluvialis may improve the skin condition in not only in women but also in men. | Abadie-Guedes R, Guedes RC, Bezerra RS (2012)
The impairing effect of acute ethanol on spreading depression is antagonized by astaxanthin in rats of 2 young-adult ages.
Alcoholism, clinical and experimental research 36, 1563-1567 [PubMed:22432539]
[show Abstract]
BackgroundEthanol (EtOH) abuse and insufficient ingestion of antioxidants are external factors that can alter brain electrophysiology. Our previous studies have demonstrated that the excitability-related brain electrophysiological phenomenon known as cortical spreading depression (CSD) was facilitated by chronic EtOH intake, and chronic treatment with carotenoids attenuated this effect. Here, we investigated the acute effect of a single EtOH administration on CSD in young and adult rats previously (1 hour) treated with 10 μg/kg of astaxanthin.MethodsMale Wistar rats (5 young- and 5 adult groups, 60 to 80 and 150 to 180 days of age, respectively) were treated by 2 gavage procedures at 1-hour interval as follows: groups 1 and 2 received astaxanthin in gavage I combined with EtOH (group 1) or water (group 2) in gavage II; groups 3 and 4 received olive oil (the vehicle in which astaxanthin was dissolved) in gavage I combined with EtOH (group 3) or water (group 4) in gavage II; group 5 received water in gavage I combined with EtOH in gavage II. CSD was recorded on the cortical surface for 4 hours.ResultsCompared to the respective water and oil controls (groups 2 and 4; CSD velocities: 3.73 ± 0.09 and 3.78 ± 0.07 mm/min in the young groups; 2.99 ± 0.10 and 3.05 ± 0.19 mm/min in the adult groups), a single dose of EtOH (groups 3 and 5) decreased CSD propagation velocities (3.29 ± 0.23 and 3.16 ± 0.10 mm/min in the young groups; 2.71 ± 0.27 and 2.75 ± 0.31 mm/min in the adult groups). Astaxanthin antagonized the impairing effect of acute EtOH on CSD (group 1; mean velocity: 3.70 ± 0.19 and 3.13 ± 0.16 mm/min for the young and adult groups, respectively).ConclusionsThe results showed an antagonistic effect of acute EtOH treatment on CSD propagation that was reverted by astaxanthin. The EtOH-astaxanthin interaction was not influenced by the age, as it was found in both young and adult animals. | Ryu SK, King TJ, Fujioka K, Pattison J, Pashkow FJ, Tsimikas S (2012)
Effect of an oral astaxanthin prodrug (CDX-085) on lipoprotein levels and progression of atherosclerosis in LDLR(-/-) and ApoE(-/-) mice.
Atherosclerosis 222, 99-105 [PubMed:22406426]
[show Abstract]
UnlabelledOxidative stress and inflammation are key promoters of atherosclerosis and myocardial damage. When orally administered, the novel astaxanthin prodrug CDX-085 delivers high levels of the xanthophyll antioxidant astaxanthin that protects LDL from oxidation and reduces primary thrombosis. In this study, we analyzed whether delivery of astaxanthin from administration of the CDX-085 prodrug reduces plasma lipoprotein levels and the progression of atherosclerosis in low-density lipoprotein receptor negative (LDLR(-/-)) and apolipoprotein E deficient (ApoE(-/-)) mice.MethodsRelative circulating levels of astaxanthin derived from CDX-085 administration compared to administration of pure astaxanthin was initially evaluated in a canine model. In mouse Study #1, 16 wild-type and 16 LDLR(-/-) mice on 0.5% cholesterol diet supplemented with either 0.0%, 0.08%, 0.2% and 0.4% CDX-085 were used to assess plasma levels and lipoprotein biodistribution measured by FPLC after 4 weeks treatment. In Study #2, 36 male LDLR(-/-) mice were randomized to a 0.5% cholesterol chow diet (CHOW group, n=12) or 0.5% cholesterol chow fortified with 0.08% CDX-085 (n=12) or 0.5% cholesterol chow with 0.4% CDX-085 (n=12) for 12 weeks. In Study #3, 34 male ApoE(-/-) mice were randomized in the same fashion as the Study #2 and fed similar diets for 9 weeks.ResultsCDX-085 administration was shown to result in significantly higher levels of circulating astaxanthin (p<0.001 ANOVA) over a 72 h period compared to pure, non-esterified astaxanthin in a single-dose pharmacokinetic study in beagles. In Study #1, plasma astaxanthin levels were 5-9-fold higher in LDLR(-/-) mice compared to wild-type mice. Astaxanthin was highly distributed among all lipoprotein fractions, generally reflecting cholesterol content of lipoproteins. In Study #2, administration of CDX-085 resulted in significantly lower total cholesterol levels (528±68 mg/dL vs. 550±67 mg/dL vs. 602±80 mg/dL, p=0.047) and aortic arch atherosclerosis (9.0±4.2% vs. 9.8±3.5% vs. 13.2±3.6%, p=0.023) in the 0.4% CDX-085 group compared to the 0.08% CDX-085 and CHOW groups, respectively. In ApoE(-/-) mice, a 72% reduction in triglycerides in the 0.4% CDX-085 group and 50% reduction in the 0.08% CDX-085 groups was noted compared to CHOW group (final levels 17±11 mg/dL vs. 30±15 mg/dL vs. 60±32 mg/dL, respectively, p=0.001).ConclusionOral administration of the novel astaxanthin prodrug CDX-085 shows that it distributes among lipoproteins. CDX-085 lowers total cholesterol and aortic arch atherosclerosis in LDLR(-/-) mice and triglyceride levels in ApoE(-/-) mice and shows promise for further evaluation in human studies. | Ning Y, Li Q, Chen F, Yang N, Jin Z, Xu X (2012)
Low-cost production of 6G-fructofuranosidase with high value-added astaxanthin by Xanthophyllomyces dendrorhous.
Bioresource technology 104, 660-667 [PubMed:22119431]
[show Abstract]
The effects of medium composition and culture conditions on the production of (6)G-fructofuranosidase with value-added astaxanthin were investigated to reduce the capital cost of neo-fructooligosaccharides (neo-FOS) production by Xanthophyllomyces dendrorhous. The sucrose and corn steep liquor (CSL) were found to be the optimal carbon source and nitrogen source, respectively. CSL and initial pH were selected as the critical factors using Plackett-Burman design. Maximum (6)G-fructofuranosidase 242.57 U/mL with 5.23 mg/L value-added astaxanthin was obtained at CSL 52.5 mL/L and pH 7.89 by central composite design. Neo-FOS yield could reach 238.12 g/L under the optimized medium conditions. Cost analysis suggested 66.3% of substrate cost was reduced compared with that before optimization. These results demonstrated that the optimized medium and culture conditions could significantly enhance the production of (6)G-fructofuranosidase with value-added astaxanthin and remarkably decrease the substrate cost, which opened up possibilities to produce neo-FOS industrially. | Liu J, Huang J, Jiang Y, Chen F (2012)
Molasses-based growth and production of oil and astaxanthin by Chlorella zofingiensis.
Bioresource technology 107, 393-398 [PubMed:22221991]
[show Abstract]
The aim of this study is to evaluate the industrial waste cane molasses as a carbon source for cell growth, lipid and astaxanthin production of Chlorella zofingiensis. Pretreated with cation exchange resin to remove the metal ions, cane molasses provided better productivities of biomass, lipid, and astaxanthin (1.55, 0.71 g L(-1)day(-1) and 1.7 mg L(-1)day(-1), respectively) than glucose. Using a strategy of semi-continuous cultures coupled with feeding at a low concentration, molasses without pretreatment has the same effect as pretreated one on supporting the algal cell growth, lipid and astaxanthin production. The efficient metabolism of molasses triggered the up-regulation of genes involved in fatty acid and also astaxanthin biosynthesis, leading to the very high production of the two metabolites. This study highlights the possibility of using C. zofingiensis to deal with industrial wastes and to produce profitable biodiesel as well as the high-value astaxanthin. | Kim DM, Hyun SS, Yun P, Lee CH, Byun SY (2012)
Identification of an emulsifier and conditions for preparing stable nanoemulsions containing the antioxidant astaxanthin.
International journal of cosmetic science 34, 64-73 [PubMed:21883294]
[show Abstract]
In this study, oil-in-water nanoemulsions of astaxanthin were prepared by high-pressure homogenization. The influence of emulsifying conditions including emulsifier type, concentration, passing time, astaxanthin concentration and coantioxidants were optimized. The stabilities of nanoemulsions were measured using zetasizer, FF-SEM, TEM, colorimeter and particle size analyzer. The mean diameter of the dispersed particles containing astaxanthin ranged from 160 to 190 nm. The size distribution was unimodal and extended from 100 to 200 nm. The nanoemulsions prepared with glyceryl citrate/lactate/linoleate/oleate (glyceryl ester) had smaller particle size and narrower size distribution than the emulsion prepared with hydrogenated lecithin. Stable incorporation of astaxanthin in nanoemulsion was performed and checked using HPLC, FF-SEM and TEM. The nanoemulsion was not significantly affected during storage under light and thermal condition for one month indicating that the nanoemulsion had a zeta potential of less than -41 mV, indicating a stable colloid. | Chan KC, Pen PJ, Yin MC (2012)
Anticoagulatory and antiinflammatory effects of astaxanthin in diabetic rats.
Journal of food science 77, H76-80 [PubMed:22309505]
[show Abstract]
Astaxanthin at 0.01 or 0.05% of the diet was supplied to diabetic rats for 12 wk. Astaxanthin intake significantly increased its deposit in plasma, and retained glutathione content, reduced the production of reactive oxygen species, interleukin-6, tumor necrosis factor-α, and monocyte chemoattractant protein-1 in blood and kidney of diabetic rats (P < 0.05). Astaxanthin treatments also significantly decreased plasma levels of C-reactive protein and von Willebrand factor in diabetic rats (P < 0.05). Astaxanthin intake at 0.05% significantly diminished plasminogen activator inhibitor-1 and factor VII activities, enhanced antithrombin-III and protein C activities in circulation (P < 0.05). These results support that astaxanthin could attenuate diabetes associated coagulatory, oxidative, and inflammatory stress. | Etoh H, Suhara M, Tokuyama S, Kato H, Nakahigashi R, Maejima Y, Ishikura M, Terada Y, Maoka T (2012)
Auto-oxidation products of astaxanthin.
Journal of oleo science 61, 17-21 [PubMed:22188802]
[show Abstract]
The auto-oxidation products of astaxanthin were investigated. Astaxanthin was allowed to react with atmospheric oxygen at 55°C in the dark for 35 days. A series of oxidative cleavage products, 7-apoastaxanthinal (1), 9-apoastaxanthinone (2), 11-apoastaxanthinal (3), 13-apoastaxanthinone (4), 15-apoastaxanthinal (5), 14'-apoastaxanthinal (6), 12'-apoastaxanthinal (7), 10'-apoastaxanthinal (8), and 8'-apoastaxanthinal (9), were identified. Among them, 3 and 6 were isolated and characterized for the first time. Cleavage of the double bond in astaxanthin was discussed on the basis of the calculation of the stable molecular energy. | Fassett RG, Coombes JS (2012)
Astaxanthin in cardiovascular health and disease.
Molecules (Basel, Switzerland) 17, 2030-2048 [PubMed:22349894]
[show Abstract]
Oxidative stress and inflammation are established processes contributing to cardiovascular disease caused by atherosclerosis. However, antioxidant therapies tested in cardiovascular disease such as vitamin E, C and β-carotene have proved unsuccessful at reducing cardiovascular events and mortality. Although these outcomes may reflect limitations in trial design, new, more potent antioxidant therapies are being pursued. Astaxanthin, a carotenoid found in microalgae, fungi, complex plants, seafood, flamingos and quail is one such agent. It has antioxidant and anti-inflammatory effects. Limited, short duration and small sample size studies have assessed the effects of astaxanthin on oxidative stress and inflammation biomarkers and have investigated bioavailability and safety. So far no significant adverse events have been observed and biomarkers of oxidative stress and inflammation are attenuated with astaxanthin supplementation. Experimental investigations in a range of species using a cardiac ischaemia-reperfusion model demonstrated cardiac muscle preservation when astaxanthin is administered either orally or intravenously prior to the induction of ischaemia. Human clinical cardiovascular studies using astaxanthin therapy have not yet been reported. On the basis of the promising results of experimental cardiovascular studies and the physicochemical and antioxidant properties and safety profile of astaxanthin, clinical trials should be undertaken. | Hernández-Marin E, Barbosa A, Martínez A (2012)
The metal cation chelating capacity of astaxanthin. Does this have any influence on antiradical activity?
Molecules (Basel, Switzerland) 17, 1039-1054 [PubMed:22267192]
[show Abstract]
In this Density Functional Theory study, it became apparent that astaxanthin (ASTA) may form metal ion complexes with metal cations such as Ca⁺², Cu⁺², Pb⁺², Zn⁺², Cd⁺² and Hg⁺². The presence of metal cations induces changes in the maximum absorption bands which are red shifted in all cases. Therefore, in the case of compounds where metal ions are interacting with ASTA, they are redder in color. Moreover, the antiradical capacity of some ASTA-metal cationic complexes was studied by assessing their vertical ionization energy and vertical electron affinity, reaching the conclusion that metal complexes are slightly better electron donors and better electron acceptors than ASTA. | Alster J, Polívka T, Arellano JB, Hříbek P, Vácha F, Hála J, Pšenčík J (2012)
Self-assembly and energy transfer in artificial light-harvesting complexes of bacteriochlorophyll c with astaxanthin.
Photosynthesis research 111, 193-204 [PubMed:21833799]
[show Abstract]
Chlorosomes, the light-harvesting antennae of green photosynthetic bacteria, are based on large aggregates of bacteriochlorophyll molecules. Aggregates with similar properties to those in chlorosomes can also be prepared in vitro. Several agents were shown to induce aggregation of bacteriochlorophyll c in aqueous environments, including certain lipids, carotenes, and quinones. A key distinguishing feature of bacteriochlorophyll c aggregates, both in vitro and in chlorosomes, is a large (>60 nm) red shift of their Q(y) absorption band compared with that of the monomers. In this study, we investigate the self-assembly of bacteriochlorophyll c with the xanthophyll astaxanthin, which leads to the formation of a new type of complexes. Our results indicate that, due to its specific structure, astaxanthin molecules competes with bacteriochlorophylls for the bonds involved in the aggregation, thus preventing the formation of any significant red shift compared with pure bacteriochlorophyll c in aqueous buffer. A strong interaction between both the types of pigments in the developed assemblies, is manifested by a rather efficient (~40%) excitation energy transfer from astaxanthin to bacteriochlorophyll c, as revealed by fluorescence excitation spectroscopy. Results of transient absorption spectroscopy show that the energy transfer is very fast (<500 fs) and proceeds through the S(2) state of astaxanthin. | He KH, Zou XL, Liu X, Zeng HY (2012)
[Determination of canthaxanthin and astaxanthin in egg yolks by reversed phase high performance liquid chromatography with diode array detection].
Sichuan da xue xue bao. Yi xue ban = Journal of Sichuan University. Medical science edition 43, 113-117 [PubMed:22455145]
[show Abstract]
ObjectiveA method using reversed phase high performance liquid chromatography (RP-HPLC) coupled with diode array detector (DAD) was developed for the simultaneous determination of canthaxanthin and astaxanthin in egg yolks.MethodsSamples were extracted with acetonitrile in ultrasonic bath for 20 minutes and then purified by freezing-lipid filtration and solid phase extraction (SPE). After being vaporized to dryness by nitrogen blowing and made up to volume with methanol, the extract solution was chromatographically separated in C18 column with a unitary mobile phase consisting of acetonitrile. The proposed method was validated in terms of linearity, precision, accuracy, and limit of detection (LOD).ResultRegression analysis revealed a good linearity between peak area of each analyte and its concentration (r > or = 0.998). The intra- and inter-day relative standard deviations (RSDs) were less than 3.6% and 5.2%, respectively. LODs of canthaxanthin and astaxanthin were 0.035 and 0.027 microg/mL (S/N = 3). The average recoveries of canthaxanthin and astaxanthin were 91.5% and 88.7%.ConclusionThe proposed method is simple, fast and easy to apply. | Chiou TH, Place AR, Caldwell RL, Marshall NJ, Cronin TW (2012)
A novel function for a carotenoid: astaxanthin used as a polarizer for visual signalling in a mantis shrimp.
The Journal of experimental biology 215, 584-589 [PubMed:22279065]
[show Abstract]
Biological signals based on color patterns are well known, but some animals communicate by producing patterns of polarized light. Known biological polarizers are all based on physical interactions with light such as birefringence, differential reflection or scattering. We describe a novel biological polarizer in a marine crustacean based on linear dichroism of a carotenoid molecule. The red-colored, dichroic ketocarotenoid pigment astaxanthin is deposited in the antennal scale of a stomatopod crustacean, Odontodactylus scyllarus. Positive correlation between partial polarization and the presence of astaxanthin indicates that the antennal scale polarizes light with astaxanthin. Both the optical properties and the fine structure of the polarizationally active cuticle suggest that the dipole axes of the astaxanthin molecules are oriented nearly normal to the surface of the antennal scale. While dichroic retinoids are used as visual pigment chromophores to absorb and detect polarized light, this is the first demonstration of the use of a carotenoid to produce a polarizing signal. By using the intrinsic dichroism of the carotenoid molecule and orienting the molecule in tissue, nature has engineered a previously undescribed form of biological polarizer. | Wade NM, Anderson M, Sellars MJ, Tume RK, Preston NP, Glencross BD (2012)
Mechanisms of colour adaptation in the prawn Penaeus monodon.
The Journal of experimental biology 215, 343-350 [PubMed:22189778]
[show Abstract]
Exposure of prawns to dark- or light-coloured substrates is known to trigger a strong colour adaptation response through expansion or contraction of the colouration structures in the prawn hypodermis. Despite the difference in colour triggered by this adaptive response, total levels of the predominant carotenoid pigment, astaxanthin, are not modified, suggesting that another mechanism is regulating this phenomenon. Astaxanthin binds to a specific protein called crustacyanin (CRCN), and it is the interaction between the quantities of each of these compounds that produces the diverse range of colours seen in crustacean shells. In this study, we investigated the protein changes and genetic regulatory processes that occur in prawn hypodermal tissues during adaptation to black or white substrates. The amount of free astaxanthin was higher in animals adapted to dark substrate compared with those adapted to light substrate, and this difference was matched by a strong elevation of CRCN protein. However, there was no difference in the expression of CRCN genes either across the moult cycle or in response to background substrate colour. These results indicate that exposure to a dark-coloured substrate causes an accumulation of CRCN protein, bound with free astaxanthin, in the prawn hypodermis without modification of CRCN gene expression. On light-coloured substrates, levels of CRCN protein in the hypodermis are reduced, but the carotenoid is retained, undispersed in the hypodermal tissue, in an esterified form. Therefore, the abundance of CRCN protein affects the distribution of pigment in prawn hypodermal tissues, and is a crucial regulator of the colour adaptation response in prawns. |
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