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Astaxanthin
Terms modified by Astaxanthin Selected AbstractsSUPERCRITICAL CO2/ETHANOL EXTRACTION OF ASTAXANTHIN FROM BLUE CRAB (CALLINECTES SAPIDUS) SHELL WASTEJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2001LETICIA FÉLIX-VALENZUELA ABSTRACT Astaxanthin (AX) is the major naturally occurring carotenoid pigment in marine crustaceans and the flesh of salmonids. These organisms are unable to synthesize AX de novo and when farmed commercially, require it in their feed. The high cost of synthetic AX has promoted research into new natural sources of ihe pigment, such as crustacean wastes. In this work, AX from demineralized crab (Callinectes sapidusj shell waste was extracted with a mixture of supercritical C2 and ethanol as a cosolvent. The effect of total solids load, pressure and temperature was assessed by response surface methodology (RSM). Extracted AX was determined by HPLC. The experimental data were fined to a second order model whereby the conditions for maximum extraction yield were defined (, 34 MPa, 45C and solids load of 25 g). Pressure and solids load were the most important factors affecting AX extraction yields. [source] In vivo astaxanthin treatment partially prevents antioxidant alterations in dental pulp from alloxan-induced diabetic ratsINTERNATIONAL ENDODONTIC JOURNAL, Issue 11 2010M. F. Leite Leite MF, de Lima A, Massuyama MM, Otton R.In vivo astaxanthin treatment partially prevents antioxidant alterations in dental pulp from alloxan-induced diabetic rats. International Endodontic Journal, 43, 959,967, 2010. Abstract Aim, To evaluate the effect of astaxanthin on antioxidant parameters of dental pulp from diabetic rats. The hypothesis tested was that supplementation of diabetic rats with astaxanthin might eliminate, or at least attenuate, the defect in their antioxidative status. Methodology, Wistar rats (n = 32) were divided into four groups: untreated control, treated control, untreated diabetic and treated diabetic rats. A prophylactic dose of astaxanthin (20 mg kg,1 body weight) was administered daily by gavage for 30 days. On day 23, diabetes was induced by injection of alloxan (60 mg kg,1 body weight). After 7 days of diabetes induction, the rats were killed, and pulp tissue from incisor teeth removed. Superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and reductase activities were determined. Data were compared by anova and the Newman,Keuls test (P < 0.05). Results, Diabetes caused a reduction in SOD, GPx and reductase activity in dental pulp tissue. Astaxanthin had no effect on SOD and catalase activities; however, it stimulated GPx in control and diabetic rats. Conclusions, Diabetes altered the antioxidant system in dental pulp tissue; astaxanthin partially improved the diabetic complications. [source] Astaxanthin protects mesangial cells from hyperglycemia-induced oxidative signaling,JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 6 2008Emiko Manabe Abstract Astaxanthin (ASX) is a carotenoid that has potent protective effects on diabetic nephropathy in mice model of type 2 diabetes. In this study, we investigated the protective mechanism of ASX on the progression of diabetic nephropathy using an in vitro model of hyperglycemia, focusing on mesangial cells. Normal human mesangial cells (NHMCs) were cultured in the medium containing normal (5 mM) or high (25 mM) concentrations of D -glucose. Reactive oxygen species (ROS) production, the activation of nuclear transcription factors such as nuclear factor kappa B (NF,B) and activator protein-1 (AP-1), and the expression/production of transforming growth factor-beta 1 (TGF,1) and monocyte chemoattractant protein-1 (MCP-1) were evaluated in the presence or absence of ASX. High glucose (HG) exposure induced significant ROS production in mitochondria of NHMCs, which resulted in the activation of transcription factors, and subsequent expression/production of cytokines that plays an important role in the mesangial expansion, an important event in the pathogenesis of diabetic nephropathy. ASX significantly suppressed HG-induced ROS production, the activation of transcription factors, and cytokine expression/production by NHMCs. In addition, ASX accumulated in the mitochondria of NHMCs and reduced the production of ROS-modified proteins in mitochondria. ASX may prevent the progression of diabetic nephropathy mainly through ROS scavenging effect in mitochondria of mesangial cells and thus is expected to be very useful for the prevention of diabetic nephropathy. J. Cell. Biochem. 103: 1925,1937, 2007. © 2007 Wiley-Liss, Inc. [source] SUPERCRITICAL CO2/ETHANOL EXTRACTION OF ASTAXANTHIN FROM BLUE CRAB (CALLINECTES SAPIDUS) SHELL WASTEJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2001LETICIA FÉLIX-VALENZUELA ABSTRACT Astaxanthin (AX) is the major naturally occurring carotenoid pigment in marine crustaceans and the flesh of salmonids. These organisms are unable to synthesize AX de novo and when farmed commercially, require it in their feed. The high cost of synthetic AX has promoted research into new natural sources of ihe pigment, such as crustacean wastes. In this work, AX from demineralized crab (Callinectes sapidusj shell waste was extracted with a mixture of supercritical C2 and ethanol as a cosolvent. The effect of total solids load, pressure and temperature was assessed by response surface methodology (RSM). Extracted AX was determined by HPLC. The experimental data were fined to a second order model whereby the conditions for maximum extraction yield were defined (, 34 MPa, 45C and solids load of 25 g). Pressure and solids load were the most important factors affecting AX extraction yields. [source] Astaxanthin, a dietary carotenoid, protects retinal cells against oxidative stress in-vitro and in mice in-vivoJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 10 2008Yoshimi Nakajima We have investigated whether astaxanthin exerted neuroprotective effects in retinal ganglion cells in-vitro and in-vivo. In-vitro, retinal damage was induced by 24-h hydrogen peroxide (H2O2) exposure or serum deprivation, and cell viability was measured using a WST assay. In cultured retinal ganglion cells (RGC-5, a rat ganglion cell-line transformed using E1A virus), astaxanthin inhibited the neurotoxicity induced by H2O2 or serum deprivation, and reduced the intracellular oxidation induced by various reactive oxygen species (ROS). Furthermore, astaxanthin decreased the radical generation induced by serum deprivation in RGC-5. In mice in-vivo, astaxanthin (100 mg kg,1, p.o., four times) reduced the retinal damage (a decrease in retinal ganglion cells and in thickness of inner plexiform layer) induced by intravitreal N -methyl- d -aspartate (NMDA) injection. Furthermore, astaxanthin reduced the expressions of 4-hydroxy-2-nonenal (4-HNE)-modified protein (indicator of lipid peroxidation) and 8-hydroxy-deoxyguanosine (8-OHdG; indicator of oxidative DNA damage). These findings indicated that astaxanthin had neuroprotective effects against retinal damage in-vitro and in-vivo, and that its protective effects may have been partly mediated via its antioxidant effects. [source] ACCUMULATION OF OLEIC ACID IN HAEMATOCOCCUS PLUVIALIS (CHLOROPHYCEAE) UNDER NITROGEN STARVATION OR HIGH LIGHT IS CORRELATED WITH THAT OF ASTAXANTHIN ESTERS1JOURNAL OF PHYCOLOGY, Issue 2 2002Mirash Zhekisheva The chlorophyte Haematococcus pluvialis accumulates large quantities of astaxanthin under stress conditions. Under either nitrogen starvation or high light, the production of each picogram of astaxanthin was accompanied by that of 5 or 3,4 pg of fatty acids, respectively. In both cases, the newly formed fatty acids, consisting mostly of oleic (up to 34% of fatty acids in comparison with 13% in the control), palmitic, and linoleic acids, were deposited mostly in triacylglycerols. Furthermore, the enhanced accumulation of oleic acid was linearily correlated with that of astaxanthin. Astaxanthin, which is mostly monoesterified, is deposited in globules made of triacylglycerols. We suggest that the production of oleic acid-rich triacylglycerols on the one hand and the esterification of astaxanthin on the other hand enable the oil globules to maintain the high content of astaxanthin esters. [source] Effects of dietary supplementation of alga Haematococcus pluvialis (Flotow), synthetic astaxanthin and ,-carotene on survival, growth, and pigment distribution of red devil, Cichlasoma citrinellum (Günther)AQUACULTURE RESEARCH, Issue 8 2009C-H Pan Abstract Dietary carotenoids of various types and concentration can affect the pigmentation efficiency in an ornamental fish red devil, Cichlasoma citrinellum. Astaxanthin (AX) containing alga Haematococcus pluvialis, a synthetic AX, and a synthetic ,-carotene (BC) were supplemented in formulated diets at two concentrations, 80 and 160 mg kg,1, resulting in six pigmented diets. Formulated diet without carotenoids supplementation served as a control. These diets were fed to the fish, for 8 weeks. Astaxanthin dominated in body carotenoids deposition. Dietary BC hardly had contribution to body AX. Control fish had much lower AX content in skin, fin and muscle than fish fed pigmented diets, but had equal AX content in liver, intestine and gonad as those fish. Dietary synthetic AX had equal efficiency in depositing AX in skin and fin as natural AX but higher efficiency in gonad than natural AX. Fish fed AX supplemented at 160 mg kg,1, either natural or synthetic AX, had higher AX content in skin than fish at 80 mg kg,1 but had equal AX content in fin as fish at 80 mg kg,1. Disregarding the treatment effects, the overall average AX content in tissue in descending order was gonad>fin,(intestine=skin)>liver>muscle. [source] Selective Extraction of Free Astaxanthin from Haematococcus Culture Using a Tandem Organic Solvent SystemBIOTECHNOLOGY PROGRESS, Issue 4 2007Chang Duk Kang A novel tandem solvent process of dodecane and methanol was developed for the selective extraction of free astaxanthin from red encysted Haematococcus culture. The process consists of dodecane extraction for astaxanthin mixture from the culture (stage 1) and methanol extraction for free astaxanthin from the dodecane extract (stage 2). In the first stage, astaxanthin mixture was directly extracted to dodecane from the culture broth without cell harvest process, followed by a rapid separation of the dodecane extract and the culture medium containing cell debris by simple settling. In the second stage, free astaxanthin was selectively collected to methanol from the dodecane extract, accompanied with saponification of astaxanthin-esters by the addition of NaOH to methanol. During saponification, use of the optimum NaOH concentration (0.02 M) and low temperature (4 °C) reaction minimized the degradation of free astaxanthin, resulting in a total recovery yield of free astaxanthin of over 85%. The free-astaxanthin-containing methanol extract was also simply separated from dodecane by gravity settling, after which the astaxanthin-free dodecane was effectively recycled to the first stage, yielding a stable extractability of astaxanthin mixture during repeated extraction. Our results indicate the potential of the proposed tandem solvent process as an alternative extraction technology for the high-value antioxidant Haematococcus astaxanthin. [source] Astaxanthin formation in the marine photosynthetic bacterium Rhodovulum sulfidophilum expressing crtI, crtY, crtW and crtZFEMS MICROBIOLOGY LETTERS, Issue 1 2006Daikichi Mukoyama Abstract This study reports the production of astaxanthin in the photosynthetic bacterium Rhodovulum sulfidophilum, which has adequate precursor pools and storage capabilities for heterologous carotenoid production. Chemical mutagenesis was carried out using ethylmethane sulfonate to produce mutants with a modified carotenoid biosynthesis pathway downstream of phytoene. Stable green- and gray-colored mutants were selected. Green mutants contained neurosporene or chloroxanthin as their major carotenoid (>90%), while the gray mutants accumulated phytoene. We previously demonstrated the production of ,-carotene in Rhodovulum sulfidophilum by cloning the Erythrobacter longus crtI (phytoene dehydrogenase) and crtY (lycopene cyclase) genes. In the present study, an expression vector for astaxanthin production was constructed that contained the Paracoccus crtW (,-carotene oxygenase) and crtZ (,-carotene hydroxylase) genes in addition to the E. longus crtI and crtY genes. A transconjugant, which can synthesize astaxanthin, was successfully generated (2.0 ,g g,1 DCW). [source] Bioconversions of maize residues to value-added coproducts using yeast-like fungi,FEMS YEAST RESEARCH, Issue 2 2003Timothy D Leathers Abstract Agricultural residues are abundant potential feedstocks for bioconversions to industrial fuels and chemicals. Every bushel of maize (approximately 25 kg) processed for sweeteners, oil, or ethanol generates nearly 7 kg of protein- and fiber-rich residues. Currently these materials are sold for very low returns as animal feed ingredients. Yeast-like fungi are promising biocatalysts for conversions of agricultural residues. Although corn fiber (pericarp) arabinoxylan is resistant to digestion by commercially available enzymes, a crude mixture of enzymes from the yeast-like fungus Aureobasidium partially saccharifies corn fiber without chemical pretreatment. Sugars derived from corn fiber can be converted to ethanol or other valuable products using a variety of naturally occurring or recombinant yeasts. Examples are presented of Pichia guilliermondii strains for the conversion of corn fiber hydrolysates to the alternative sweetener xylitol. Corn-based fuel ethanol production also generates enormous volumes of low-value stillage residues. These nutritionally rich materials are prospective substrates for numerous yeast fermentations. Strains of Aureobasidium and the red yeast Phaffia rhodozyma utilize stillage residues for production of the polysaccharide pullulan and the carotenoid astaxanthin, respectively. [source] In vivo astaxanthin treatment partially prevents antioxidant alterations in dental pulp from alloxan-induced diabetic ratsINTERNATIONAL ENDODONTIC JOURNAL, Issue 11 2010M. F. Leite Leite MF, de Lima A, Massuyama MM, Otton R.In vivo astaxanthin treatment partially prevents antioxidant alterations in dental pulp from alloxan-induced diabetic rats. International Endodontic Journal, 43, 959,967, 2010. Abstract Aim, To evaluate the effect of astaxanthin on antioxidant parameters of dental pulp from diabetic rats. The hypothesis tested was that supplementation of diabetic rats with astaxanthin might eliminate, or at least attenuate, the defect in their antioxidative status. Methodology, Wistar rats (n = 32) were divided into four groups: untreated control, treated control, untreated diabetic and treated diabetic rats. A prophylactic dose of astaxanthin (20 mg kg,1 body weight) was administered daily by gavage for 30 days. On day 23, diabetes was induced by injection of alloxan (60 mg kg,1 body weight). After 7 days of diabetes induction, the rats were killed, and pulp tissue from incisor teeth removed. Superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and reductase activities were determined. Data were compared by anova and the Newman,Keuls test (P < 0.05). Results, Diabetes caused a reduction in SOD, GPx and reductase activity in dental pulp tissue. Astaxanthin had no effect on SOD and catalase activities; however, it stimulated GPx in control and diabetic rats. Conclusions, Diabetes altered the antioxidant system in dental pulp tissue; astaxanthin partially improved the diabetic complications. [source] Antiadult T-cell leukemia effects of brown algae fucoxanthin and its deacetylated product, fucoxanthinolINTERNATIONAL JOURNAL OF CANCER, Issue 11 2008Chie Ishikawa Abstract Adult T-cell leukemia (ATL) is a fatal malignancy of T lymphocytes caused by human T-cell leukemia virus type 1 (HTLV-1) infection and remains incurable. Carotenoids are a family of natural pigments and have several biological functions. Among carotenoids, fucoxanthin is known to have antitumorigenic activity, but the precise mechanism of action is not elucidated. We evaluated the anti-ATL effects of fucoxanthin and its metabolite, fucoxanthinol. Both carotenoids inhibited cell viability of HTLV-1-infected T-cell lines and ATL cells, and fucoxanthinol was approximately twice more potent than fucoxanthin. In contrast, other carotenoids, ,-carotene and astaxanthin, had mild inhibitory effects on HTLV-1-infected T-cell lines. Importantly, uninfected cell lines and normal peripheral blood mononuclear cells were resistant to fucoxanthin and fucoxanthinol. Both carotenoids induced cell cycle arrest during G1 phase by reducing the expression of cyclin D1, cyclin D2, CDK4 and CDK6, and inducing the expression of GADD45,, and induced apoptosis by reducing the expression of Bcl-2, XIAP, cIAP2 and survivin. The induced apoptosis was associated with activation of caspase-3, -8 and -9. Fucoxanthin and fucoxanthinol also suppressed I,B, phosphorylation and JunD expression, resulting in inactivation of nuclear factor-,B and activator protein-1. Mice with severe combined immunodeficiency harboring tumors induced by inoculation of HTLV-1-infected T cells responded to treatment with fucoxanthinol with suppression of tumor growth, showed extensive tissue distribution of fucoxanthinol, and the presence of therapeutically effective serum concentrations of fucoxanthinol. Our preclinical data suggest that fucoxanthin and fucoxanthinol could be potentially useful therapeutic agents for patients with ATL. © 2008 Wiley-Liss, Inc. [source] Red-winged blackbirds Agelaius phoeniceus use carotenoid and melanin pigments to color their epauletsJOURNAL OF AVIAN BIOLOGY, Issue 6 2004Kevin J. McGraw Over the past three decades, the red-winged blackbird Agelaius phoeniceus has served as a model species for studies of sexual selection and the evolution of ornamental traits. Particular attention has been paid to the role of the colorful red-and-yellow epaulets that are striking in males but reduced in females and juveniles. It has been assumed that carotenoid pigments bestow the brilliant red and yellow colors on epaulet feathers, but this has never been tested biochemically. Here, we use high-performance liquid chromatography (HPLC) to describe the pigments present in these colorful feathers. Two red ketocarotenoids (astaxanthin and canthaxanthin) are responsible for the bright red hue of epaulets. Two yellow dietary precursors pigments (lutein and zeaxanthin) are also present in moderately high concentrations in red feathers. After extracting carotenoids, however, red feathers remained deep brown in color. HPLC tests show that melanin pigments (primarily eumelanin) are also found in the red-pigmented barbules of epaulet feathers, at an approximately equal concentration to carotenoids. This appears to be an uncommon feature of carotenoid-based ornamental plumage in birds, as was shown by comparable analyses of melanin in the yellow feathers of male American goldfinches Carduelis tristis and the red feathers of northern cardinals Cardinalis cardinalis, in which we detected virtually no melanins. Furthermore, the yellow bordering feathers of male epaulets are devoid of carotenoids (except when tinged with a carotenoid-derived pink coloration on occasion) and instead are comprised of a high concentration of primarily phaeomelanin pigments. The dual pigment composition of red epaulet feathers and the melanin-only basis for yellow coloration may have important implications for the honesty-reinforcing mechanisms underlying ornamental epaulets in red-winged blackbirds, and shed light on the difficulties researchers have had to date in characterizing the signaling function of this trait. As in several other birds, the melanic nature of feathers may explain why epaulets are used largely to settle aggressive contests rather than to attract mates. [source] The use of colloidal gas aphrons as novel downstream processing for the recovery of astaxanthin from cells of Phaffia rhodozymaJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2008Maria Dermiki Abstract BACKGROUND: There is an increasing interest in obtaining natural products with bioactive properties, using fermentation technology. However, the downstream processing consisting of multiple steps can be complicated, leading to increase in the final cost of the product. Therefore there is a need for integrated, cost-effective and scalable separation processes. RESULTS: The present study investigates the use of colloidal gas aphrons (CGA), which are surfactant-stabilized microbubbles, as a novel method for downstream processing. More particularly, their application for the recovery of astaxanthin from the cells of Phaffia rhodozyma is explored. Research carried out with standard solutions of astaxanthin and CGA generated from the cationic surfactant hexadecyl trimethyl ammonium bromide (CTAB) showed that up to 90% recovery can be achieved under optimum conditions, i.e., pH 11 with NaOH 0.2 mol L,1. In the case of the cells' suspension from the fermentation broth, three different approaches were investigated: (a) the conventional integrated approach where CGA were applied directly; (b) CGA were applied to the clarified suspension of cells; and finally (c) the in situ approach, where CGA are generated within the clarified suspension of cells. Interestingly, in the case of the whole suspension (approach a) highest recoveries (78%) were achieved under the same conditions found to be optimal for the standard solutions. In addition, up to 97% recovery of total carotenoids could be achieved from the clarified suspension after pretreatment with NaOH. This pretreatment led to maximum cell disruption as well as optimum conditioning for subsequent CGA separation. CONCLUSIONS: These results demonstrate the potential of CGA for the recovery of bioactive components from complex feedstock. Copyright © 2008 Society of Chemical Industry [source] Recovery of Components from Shrimp (Xiphopenaeus kroyeri) Processing Waste by Enzymatic HydrolysisJOURNAL OF FOOD SCIENCE, Issue 5 2006Helenice Duarte De Holanda ABSTRACT:, Industrial shrimp waste is a good source of protein, chitin, and carotenoids. In general, this waste is discarded with no attempt to use it, thus contributing to environmental pollution. This study was aimed at recovering the 3 main components of industrial shrimp waste, protein, chitin, and astaxanthin, using enzymatic treatment with Alcalase and pancreatin. An increase in the degree of hydrolysis (DH) from 6% to 12% resulted in 26% to 28% protein recovery. Alcalase was more efficient than pancreatin, increasing the recovery of protein from 57.5% to 64.6% and of astaxanthin from 4.7 to 5.7 mg astaxanthin/100 g of dry waste, at a DH of 12%. The enzymatic hydrolysis of the industrial waste from Xiphopenaeus kroyeri shrimp using Alcalase allowed for 65% protein recovery in the form of hydrolysates, in addition to providing suitable conditions for the recovery of astaxanthin and chitin. [source] Astaxanthin, a dietary carotenoid, protects retinal cells against oxidative stress in-vitro and in mice in-vivoJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 10 2008Yoshimi Nakajima We have investigated whether astaxanthin exerted neuroprotective effects in retinal ganglion cells in-vitro and in-vivo. In-vitro, retinal damage was induced by 24-h hydrogen peroxide (H2O2) exposure or serum deprivation, and cell viability was measured using a WST assay. In cultured retinal ganglion cells (RGC-5, a rat ganglion cell-line transformed using E1A virus), astaxanthin inhibited the neurotoxicity induced by H2O2 or serum deprivation, and reduced the intracellular oxidation induced by various reactive oxygen species (ROS). Furthermore, astaxanthin decreased the radical generation induced by serum deprivation in RGC-5. In mice in-vivo, astaxanthin (100 mg kg,1, p.o., four times) reduced the retinal damage (a decrease in retinal ganglion cells and in thickness of inner plexiform layer) induced by intravitreal N -methyl- d -aspartate (NMDA) injection. Furthermore, astaxanthin reduced the expressions of 4-hydroxy-2-nonenal (4-HNE)-modified protein (indicator of lipid peroxidation) and 8-hydroxy-deoxyguanosine (8-OHdG; indicator of oxidative DNA damage). These findings indicated that astaxanthin had neuroprotective effects against retinal damage in-vitro and in-vivo, and that its protective effects may have been partly mediated via its antioxidant effects. [source] 71 Proteomics of haematococcus pluvialis: new opportunities for study of genomics of a non-sequenced speciesJOURNAL OF PHYCOLOGY, Issue 2003Q. Hu The green alga, Haematococcus pluvialis, has become a model organism for commercial production of the high-value carotenoid astaxanthin. H. Pluvialis has also drawn significant scientific attention because fundamental biological questions relating to the massive cellular accumulation of astaxanthin have to be addressed in order to improve the yield and quality of the algal biomass. However, research has been impeded by the lack of molecular background information on this non-sequenced species. A combination of classical biochemistry with a state-of-the-art proteomic approach was used to address these questions. This was possible by taking advantage of information already available for homologous genes/gene-products in organisms whose genomes have been sequenced. The approach involved isolation of subsets of the proteome from subcellular compartments/organelles of an organism by one- or two-dimensional electrophoresis (1-DE or 2-DE) and their identification by N-terminal sequencing and peptide mass fingerprinting (PMF), involving matrix-assisted laser desorption/ionization and time-of-flight (MALDI-TOF) mass spectrometry coupled with bioinformatics. Based upon the information obtained from the combined methods, expression and physiological functions of specific genes/encoded proteins may be deduced. Examples include profiling of cell wall proteins, biogenesis and protein composition of lipid bodies, and expression patterns of soluble proteins under stress conditions. Advantages and limitations of the method for non-sequenced organisms and for cross-species protein identification will also be discussed. [source] ACCUMULATION OF OLEIC ACID IN HAEMATOCOCCUS PLUVIALIS (CHLOROPHYCEAE) UNDER NITROGEN STARVATION OR HIGH LIGHT IS CORRELATED WITH THAT OF ASTAXANTHIN ESTERS1JOURNAL OF PHYCOLOGY, Issue 2 2002Mirash Zhekisheva The chlorophyte Haematococcus pluvialis accumulates large quantities of astaxanthin under stress conditions. Under either nitrogen starvation or high light, the production of each picogram of astaxanthin was accompanied by that of 5 or 3,4 pg of fatty acids, respectively. In both cases, the newly formed fatty acids, consisting mostly of oleic (up to 34% of fatty acids in comparison with 13% in the control), palmitic, and linoleic acids, were deposited mostly in triacylglycerols. Furthermore, the enhanced accumulation of oleic acid was linearily correlated with that of astaxanthin. Astaxanthin, which is mostly monoesterified, is deposited in globules made of triacylglycerols. We suggest that the production of oleic acid-rich triacylglycerols on the one hand and the esterification of astaxanthin on the other hand enable the oil globules to maintain the high content of astaxanthin esters. [source] Introductory studies on the growth and characterization of carotenoid solids: an approach to carotenoid solid engineeringJOURNAL OF RAMAN SPECTROSCOPY, Issue 6-7 2001Yuzo Mori Solids of seven all- trans isomeric carotenoids, ,-carotene, ,-apo-8,-carotenal, astaxanthin, canthaxanthin, spheroidene, lycopene and zeaxanthin, were studied in the forms of KBr disks, aggregates, thin films and single crystals in an effort to understand and control the molecular arrangement of the solids. Optical absorption and resonance Raman scattering were adopted to characterize the arrangements. Card-packed arrangements and head-to-tail arrangements were realized by changing either the end groups or the growth process. These studies, which reveal the elementary engineering of solid growth and its characterization, may open up carotenoid solid engineering to develop useful applications of the materials in the fields of electronics, photonics and mechanical engineering. Copyright © 2001 John Wiley & Sons, Ltd. [source] Mobile phase additives for enhancing the chromatographic performance of astaxanthin on nonendcapped polymeric C30 -bonded stationary phasesJOURNAL OF SEPARATION SCIENCE, JSS, Issue 1 2009Philipp Kaiser Abstract Astaxanthin shows peak deformation and reduced peak area response when eluted with methanol and methyl tert -butyl ether on nonendcapped polymeric C30 -bonded HPLC phases. The present study tested different column manufacturers, column batches, and ten mobile phase additives including acids, bases, buffers, complexing and antioxidant agents for improvement of peak shape and peak area response. Concerning chromatographic benefits and feasibility, ammonium acetate was found to be the best additive followed by triethylamine for all columns tested. Variation of the mobile phase pH equivalent and the column temperature showed no synergistic effects on peak shape and peak area response. Results indicate that peak tailing and variation of peak area response are due to different on-column effects. Possible mechanisms of the observed phenomenon will be discussed. [source] Effect of Dietary Carotenoids on Skin Color and Pigments of False Clownfish, Amphiprion ocellaris, CuvierJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2010Inayah Yasir This study evaluated the role of supplemented dietary carotenoids in regulating the skin color and pigments of the false clownfish, Amphiprion ocellaris. Three carotenoid types, such as astaxanthin, ,-carotene, and canthaxanthin, were added to the basal diet at four pigment doses (0, 20, 50, and 100 ppm). Carotenoid diets were feed for 5 wk and then withdrawn from the diet for three additional wk during an 8-wk trial. The dose of each diet did not change the overall color hue, brightness, or saturation, but astaxanthin was the only carotenoid that enhanced red hue by the end of Week 5. The withdrawal of astaxanthin from the diet did not reduce the red hue, but reduced saturation. In contrast, the withdrawal of dietary ,-carotene or canthaxanthin reduced color saturation and brightness, but did not affect color hue. Dietary astaxanthin increased skin astaxanthin in Week 1 and skin zeaxanthin in Week 5. The withdrawal of astaxanthin escalated skin canthaxanthin and zeaxanthin by Week 8. Dietary ,-carotene suppressed skin ,-carotene, but enhanced skin zeaxanthin by Week 8. Although skin canthaxanthin was enhanced by dietary ,-carotene from Week 5 onward, dietary ,-carotene at 100 ppm maximized skin canthaxanthin by Week 8. Interestingly, dietary canthaxanthin suppressed skin canthaxanthin and zeaxanthin, but increased ,-carotene. This study suggests that astaxanthin has the potential to enhance the red hue on clownfish skin and its withdrawal from the diet did not fade the red hue of the skin. [source] Transcriptional regulation of connexin 43 expression by retinoids and carotenoids: Similarities and differencesMOLECULAR CARCINOGENESIS, Issue 2 2005Alex L. Vine Abstract Gap junctions, connexons, are formed by assembly of trans-membrane connexin proteins and have multiple functions including the coordination of cell responses. Most human tumors are deficient in gap junctional communication (GJC) and restoration of GJC by forced expression of connexins reduces indices of neoplasia. Expression of connexin 43 (Cx43), the most widely-expressed connexin family member, is upregulated by cancer-preventive retinoids and carotenoids in normal and preneoplastic cells; an action considered of mechanistic significance. However, the molecular mechanism for upregulated expression is poorly understood. The retinoic acid receptor antagonist Ro 41-5253 was capable of suppressing retinoid-induction Cx43 luciferase reporter construct in F9 cells, but did not suppress reporter activity induced by the non-pro-vitamin A carotenoids astaxanthin or lycopene, indicating that retinoids have separate mechanisms of gene activation than non-pro-vitamin A carotenoids. Neither class of compound required protein synthesis for induction of Cx43 mRNA, nor was the 5.0 h half-life of Cx43 mRNA altered, indicating direct transcriptional activation. The responsive region was found within ,158 bp and +209 bp of the transcription start site; this contains a Sp1/Sp3 GC-box to which Sp1 and Sp3 were bound, as revealed by electrophoretic mobility shift assays (EMSA), but no retinoic acid response element (RARE). Site directed mutagenesis of this GC-box resulted in increased basal levels of transcription and loss of responsiveness to a synthetic retinoid. In this construct astaxanthin and lycopene produced marginally, but not significantly higher, reporter activity than the control. © 2005 Wiley-Liss, Inc. [source] X-ray crystal structures of diacetates of 6-s- cis and 6-s- trans astaxanthin and of 7,8-didehydroastaxanthin and 7,8,7,,8,-tetradehydroastaxanthin: comparison with free and protein-bound astaxanthinsACTA CRYSTALLOGRAPHICA SECTION B, Issue 2 2009Giuditta Bartalucci The crystal structures of the 6-s- cis [s- cis -(1)] and 6-s- trans [s- trans -(1)] conformers of the diacetates of astaxanthin (AXT) and those of (3S,3,S)-7,8-didehydroastaxanthin [(3S,3,S)-3,3,-dihydroxy-7,8-didehydro-,,,-carotene-4,4,-dione (2)] and (3S,3,S)-7,8,7,,8,-tetradehydroastaxanthin [(3S,3,S)-3,3,-dihydroxy-7,8,7,,8,-tetradehydro-,,,-carotene-4, 4,-dione (3)] are reported. The conformations of these four molecules vary in particular with the angle of twist of the end rings out of the plane of the polyene chain; for s- cis -(1), the end rings are twisted out of the plane of the polyene chain by an angle of ,49.0,(5)°, and the conformation is therefore similar to that found for unesterified AXT as well as for the carotenoids, canthaxanthin and ,,,-carotene. For s- trans -(1), the end rings are coplanar with the polyene chain and its conformation is much more similar to that of the protein-bound AXT in the blue protein, crustacyanin, which is found in the shell of lobsters, although s- trans -(1) shows much less bowing of the polyene chain. In (2) and (3) the end rings are also almost coplanar with the polyene chain with the end rings in (2) in the s- cis conformation, and in (3) in the s- trans conformation. Thus, an extensive ensemble of the possible , end-ring conformations has been determined. These structures are compared with one another as well as unbound, unesterified AXT and protein-bound AXT. Also, the effect of the end-ring conformations on the colour and UV,vis spectra of the crystals was established. [source] Response of rainbow trout (Oncorhynchus mykiss) to varying dietary astaxanthin/canthaxanthin ratio: colour and carotenoid retention of the muscleAQUACULTURE NUTRITION, Issue 5 2010G. CHOUBERT Abstract Rainbow trout with an average initial weight of 160 g were fed during 42 days diets containing varied keto-carotenoids astaxanthin (Ax)/canthaxanthin (Cx) ratio, as follows: Ax 100% : Cx 0%; Ax 75% : Cx 25%; Ax 50% : Cx 50%; Ax 25% : Cx 75% and Ax 0% : Cx 100%. Muscle colour and carotenoid muscle retention were studied. Colour parameter values for mixed astaxanthin,canthaxanthin-fed fish were intermediate between those obtained for Ax 0% : Cx 100% fed fish group and for Ax 100% : Cx 0% fed fish group. Concerning muscle carotenoid retention, it has been observed that as the level of canthaxanthin in diet increased, the muscle total carotenoid retention decreased. In the mean time, as the level of canthaxanthin in diet increased, the muscle astaxanthin retention decreased while that of canthaxanthin increased. The results reported here provide further evidence of non-beneficial effects in terms of muscle colour and muscle carotenoid retention of the use of varying dietary astaxanthin/canthaxanthin ratio for feeding rainbow trout compared to values obtained for astaxanthin-only feed. [source] Calanus oil as a natural source for flesh pigmentation in Atlantic salmon (Salmo salar L.)AQUACULTURE NUTRITION, Issue 2 2009N. HYNES Abstract The present study was to understand how efficiently the astaxanthin in Calanus oil is utilized for flesh colouration in Atlantic salmon (Salmo salar). Postsmolts of the fish (309 g) were held at 7.9 °C and they were fed diets containing 20 or 60 mg astaxanthin per kilogram feed derived from a synthetic source or from Calanus oil for 181 days. Besides growth and feed intake assessments, at day 81 and 181, fish flesh were subjected to colour analysis and astaxanthin determination. Growth and feed performance did not vary between the groups. There were significant differences in the amount of astaxanthin in muscle between almost all groups both at day 81 (P < 0.05) and at day 181 (P < 0.001). However, a notable similarity between fish receiving 20 mg astaxanthin from the synthetic source and those receiving 60 mg astaxanthin from Calanus oil (P > 0.05) at day 181 indicated that comparable amounts were deposited only with the greater level of the natural source. Tristimuli colorimeter a* values support the analytical results at day 181. Although Calanus oil did serve as a natural dietary pigment source for farmed salmon, its inclusion level should provide more than 60 mg astaxanthin per kilogram feed to achieve colouration preferred by the market. [source] Use of Cyclop-eeze as a substitute for Artemia nauplii in larval rearing of giant freshwater prawn Macrobrachium rosenbergii (De Man 1879)AQUACULTURE NUTRITION, Issue 2 2007C. MOHANAKUMARAN NAIR Abstract Four feeding experiments, replacing 25% (T1), 50% (T2), 75% (T3) and 100% (T4), by dry weight, of the live feed Artemia nauplii for Cyclop-eeze, a new larval feed that was claimed to contain the highest known levels of astaxanthin and omega-3 polyunsaturated fatty acids, were compared against a control that was fed with Artemia and egg custard alone, to the larvae of giant freshwater prawn Macrobrachium rosenbergii (De Man 1879). Analysis of different production characteristics of the larvae revealed that the highest survival up to postlarvae (PL) stage was obtained for T2 in which 50% of the Artemia nauplii were replaced by Cyclop-eeze [freeze-dried (FD) deep frozen (DF)], and the highest astaxanthin content of the larval tissue obtained in T4 in which the larvae were fed 100% Cyclop-eeze, although the survival rate was the lowest in this treatment. The costs of different treatments were also compared. The Artemia consumption million,1 larvae was the highest in control (11490 g), followed by T1 (8240 g), T2 (4990 g), T3 (3730 g) and T4, which completely replaced Artemia from stage 5 onwards (1830 g). The highest consumption of Cyclop-eeze million,1 larvae was in T4 (1670 and 10 880 g), followed by T3 (850 and 5560 g), T2 (410 and 2690 g) and T1 (230 and 1490 g) of FD and DF, respectively. The astaxanthin contents of the late-stage larvae fed under the four treatments were 24.90, 27.40, 28.60 and 35.60 ,g g,1 tissue for T1, T2, T3 and T4, respectively, while that of the control was 23.70 ,g g,1. The lowest cost of live feeds million,1 PL was obtained for T2 (US$ 428.60), followed by T1 (US$ 490.46), control (US$ 529.07) and T3 (US$ 583.26), while it was the highest for T4 (US$ 890.93). The results indicated that Cyclop-eeze could economically replace Artemia nauplii at 50% level that could significantly improve the survival and carotenoid composition of the larvae of M. rosenbergii. [source] Seasonal changes in selected muscle quality parameters in Atlantic salmon (Salmo salar L.) reared under natural and continuous lightAQUACULTURE NUTRITION, Issue 3 2003U. Nordgarden Abstract In order to investigate how seasonal variation in growth affects selected fillet quality parameters, immature Atlantic salmon (Salmo salar L.) were reared under simulated natural photoperiod (SNP) for 12 months or continuous light (LL) from January to June followed by SNP until December. Photoperiod treatments advanced the growth rate pattern of the LL group compared with the SNP group and influenced macronutrient metabolism, evaluated both as trends in protein and lipid retention and in fillet lipid and protein levels. Good growth was associated with low fillet lipid and protein level, in addition to reduced levels of fillet tocopherol and astaxanthin, indicating increased oxidative stress. Elevated levels of thiobarbituric reactive substances (TBARs) further supported this. Slaughtering during periods of high growth may therefore reduce postmortem quality, both because of increased susceptibility to fillet lipid peroxidation and reduced astaxanthin levels, which were lowered in vivo and might consequently be depleted further after slaughter. Specialized use of antioxidant-rich feed prior to slaughter is suggested if slaughtering is expected to occur during periods of high growth rate. [source] The antioxidant capacity response to hypoxia stress during transportation of characins (Hyphessobrycon callistus Boulenger) fed diets supplemented with carotenoidsAQUACULTURE RESEARCH, Issue 7 2010Chih-Hung Pan Abstract This study aimed to determine whether dietary carotenoid (CD) supplements could affect the antioxidant capacity of characins Hyphessobrycon callistus upon hypoxia stress at live transportation. Two types of CD [astaxanthin (AX), ,-carotene (BC)] and their 1:1 combination (MX) at three concentrations (10, 20 and 40 mg kg,1) were supplemented, resulting in nine CD diets. After 8 weeks' rearing, the resulting fish were divided into two subgroups and exposed to hypoxia or normoxia. Hypoxia involved a gradual decrease in dissolved oxygen (DO) from 6.5 to <1.0 mg L,1. Normoxia was DO kept in saturation. Hypoxia led to an increase in the total antioxidant status (TAS), superoxide dismutase (SOD), glutathione peroxidases (GPx) and aspartate aminotransferase (AST) activity of blood serum in fish, but had no effect on alanine aminotransferase (ALT). Under hypoxia, fish fed CD diets had lower SOD, GPx and ALT activity than control fish, showing that dietary CD could increase the antioxidant capacity and protection of the liver. Dietary AX was more effective for antioxidant capacity than BC and MX when under hypoxia stress, because GPx, ALT and AST were lower in AX-fed fish. Except TAS, the other four enzyme activities showed decreasing trends with increasing dietary CD concentrations. [source] Pigmentation, carotenoids, lipid peroxides and lipid composition of red porgy (Pagrus pagrus) skin reared under open-cage conditionsAQUACULTURE RESEARCH, Issue 7 2010Noemí Tejera Abstract Pigmentation capability of red porgy (Pagrus pagrus) skin reared under open sea-cage conditions and fed an astaxanthin-enriched diet was studied. Skin lipid peroxide levels and lipid composition were also evaluated to establish the antioxidant role of astaxanthin under these sunlight-exposure conditions. Fish placed either in an offshore sea cage system (SC) or in an inland tank facility (T) housed inside a ,shade-house' enclosure were fed a commercial diet supplemented with 22 mg kg,1 astaxanthin. No differences in growth or survival were found. Both groups displayed a red skin, but SC fish presented a darker pigmentation, which externally reflected the higher deposition of melanin, astaxanthin and tunaxanthin found in its skin. The lower level of lipid peroxides found in SC fish might be related with the higher level of astaxanthin mentioned above. Nevertheless, lipid and fatty acid profiles did not show significant differences between groups. Our results indicate that sustainable production of red porgy with a natural red hue is possible on the basis of proper adjustment of two factors illumination and dietary astaxanthin. [source] Effects of different dosages of astaxanthin on giant freshwater prawn Macrobrachium rosenbergii (De Man) challenged with Lactococcus garvieaeAQUACULTURE RESEARCH, Issue 1 2009Isagani P Angeles Jr Abstract The effects of astaxanthin (AX) injected at 0.67 and 1.34 nmol g,1 BW,1 on the survival, antioxidant capacity, total haemocyte count (THC) and hepatopancreas astaxanthin content of giant freshwater prawn, Macrobrachium rosenbergii, challenged with Lactococcus garvieae were evaluated. AX-injected M. rosenbergii at 1.34 nmol g,1 BW,1 had significantly (P,0.05) higher survival rates. However, AX showed no significant effects on the capacity of certain antioxidant indicators (superoxide dismutase, glutathione peroxidase and glutathione reductase). This implies that L. garvieae infection suppressed the activity of the haemolymph antioxidant system of infected M. rosenbergii. This result suggests that the two different dosages used in this study could not exert significant effects on the tested antioxidant capacity of L. garvieae -infected M. rosenbergii. On the other hand, AX-injected M. rosenbergii at either dose showed a significant increase in the THC and hepatopancreas AX content when compared with the challenged control group. Overall, the results of this study indicate that the injected AX led to an improvement in M. rosenbergii's resistance against L. garvieae infection. [source] | |||||||||||||||||||