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Silva, Danielle Alves da. "Maximização da produção de astaxantina por Phaffia rhodozyma (Xanthophyllomyces dendrohous) utilizando água de parboilização do arroz." reponame:Repositório Institucional da FURG, 2009. http://repositorio.furg.br/handle/1/2575.
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O interesse na produção de astaxantina por fontes naturais vem aumentando significativamente nos últimos anos, devido a possibilidade de atuar como corante e sua capacidade antioxidante biológica potente. É o carotenóide principal encontrado na levedura Phaffia rhodozyma, sendo esse microrganismo adequado para o uso como fonte do pigmento industrial em razão de seu metabolismo heterotrófico, padrão de crescimento relativamente rápido, qualidade nutricional e seguro como aditivo alimentar. A presente dissertação teve como objetivo principal realizar cultivos utilizando a levedura Phaffia rhodozyma, estudando diferentes meios de cultura, empregando a água de parboilização do arroz como substrato. Inicialmente selecionou-se dentre 3 cepas de P. rhodozyma: NRRL Y-17268, NRRL Y-10921 e NRRL Y-10922, a mais promissora quanto a produção de astaxantina, utilizando glicose e sacarose como fonte de carbono. Os cultivos foram realizados em frascos agitados a 25ºC, 150rpm, por um período de 168h. Através do acompanhamento da bioprodução de astaxantina, a levedura P. rhodozyma NRRL Y-17268 foi selecionada, pois se destacou como boa produtora do carotenóide, alcançando 7,0g.L-1 de biomassa, 350,2μg.g-1 de produção de astaxantina específica e 2,4μg.mL-1 de astaxantina volumétrica, utilizando sacarose. Utilizou-se a metodologia de planejamento experimenta e análise de superfície de resposta para verificar os efeitos das variáveis em estudo e as condições que levaram a melhor bioprodução da astaxantina. Um planejamento experimental fracionário 2IV 6-2 foi realizado para determinar as variáveis que mais influenciavam na produção da astaxantina. As variáveis independentes estudadas foram concentrações de extrato de levedura (1 a 10g.L-1), extrato de malte (1 a 10g.L-1), peptona (1 a 10g.L-1), sacarose (5 a 20g.L-1), efluente da parboilização do arroz (0 a 180g.L-1) e o pH inicial do meio (4 a 6), tendo como resposta a produção de biomassa, produção de astaxantina específica e produção de astaxantina volumétrica. Os valores máximos obtidos foram 8,9g.L-1 de biomassa, 538,4μg.g-1 de astaxantina específica e 3,1μg.mL-1 de astaxantina volumétrica, em diferentes condições de composição de meio de cultivo. O extrato de levedura não apresentou efeito significativo em nenhuma das respostas avaliadas, sendo realizado um teste de Tukey na faixa de 0 a 1g.L-1. A concentração de extrato de levedura não apresentou diferença significativa, sendo retirado do meio de cultivo. No segundo planejamento foram ampliadas as faixas de estudo das variáveis selecionadas: concentrações de extrato de malte (8,75 a 16,25g.L-1), sacarose (15 a 35g.L-1), peptona (8,75 a 16,25g.L-1) e o pH mantido no ponto central 5,0. A partir dos resultados, verificou-se um incremento na concentração máxima de biomassa obtida, alcançando 10,9g.L-1 e na produção de astaxantina específica para 628,8μg.g-1. As melhores condições encontradas através das superfícies de resposta para maximização da produção de astaxantina volumétrica foram: 16,25g.L-1 de extrato de malte, 8,75g.L-1 de peptona, 15g.L-1 de sacarose e 87,5g.L-1 de água de parboilização do arroz, alcançando em torno de 5,4μg.mL-1.
The interest in astaxanthin production by natural sources has increased significantly in the last few years, because of its possibility of acting as corants and its powerfull biological antioxidant capacity. It’s the most important carotenoid found in the yeast Phaffia rhodozyma and this microorganism is appropriate to use in the source of industrial pigment due to its heterotrophic metabolism, relatively rapid growth, nutritional quality and safe as a food additive. The present dissertation had as main objective, through fermentation, using the yeast Phaffia rhodozyma studying different culture medium and the rice parboilization wastewater as a substrate. Firstly, the greatest astaxanthin producer, using glucose and sucrose as carbon source was selected amongst three strains of Phaffia rhodozyma: NRRL Y-17268, NRRL Y-10921 and NRRL Y-10922. The cultivation condition was realized in a rotatory flasks, at 25ºC, 150rpm, for 168h. Through the accompaniment of the bioproduction of astaxanthin, the yeast P. rhodozyma NRRL Y-17268 was selected, because it stood out as a good producer of the carotenoid, 7.0g.L-1 of biomass, 350.2μg.g-1 of specific production of astaxanthin and 2.4μg.mL-1 of volumetric production of astaxanthin, using sucrose. The techniques of experimental design and analysis of response surfaces were used to verify the effects of the studied variables and the condictions wich led to the best production of astaxanthin. A fractional experimental design 2IV 6-2 was used to determine the independents variables that most influenced in the production of astaxanhin. The studied independents variables were yeast extract concentration (1 to 10g.L-1), malt extract (1 to 10g.L-1), peptone (1 to 10g.L-1), sucrose (5 to 20g.L-1), rice parboilization wastewater (0 to 180g.L-1) and the initial pH (4 to 6), having as answer the biomass production, specific production of astaxanthin and volumetric production of astaxanthin. The highest values obtained were 8.9g.L-1 of biomass, 538.4μg.g-1 of specific astaxanthin and 3.1μg.mL-1 of volumetric astaxanthin, in differents conditions of composition of cultivation medium. The yeast extract didn’t show significant effect in any answer, being made a Tukey test in the range of 0 to 1g.L-1. In this test the yeast extract concentration didn’t show significant difference, then it was removed from the cultivation medium. In a second design the range were amplied: malt extract concentration (8.75 to 16.25g.L-1), sucrose (15 to 35g.L-1), peptone (8.75 to 16.25g.L-1) and the pH was maintained in the central point (5.0). From the results, verify an increased in the maximum biomass concentration obtained, reaching 10.9g.L-1 and in a specific production of astaxanthin to 628.8μg.g-1. The better conditions found through of response surface to the maximization of volumetric production of astaxanthin was: 16.25g.L-1 of malt extract, 8.75g.L-1 of peptone, 15g.L-1 of sucrose and 87.5g.L-1 of rice parboilization waste water, reaching around 5.4μg.mL-1.
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Zuluaga, tamayo Marisol. "Systèmes hydrophiles antioxydants pour applications cardiovasculaires : synthèse, caractérisation, études in vitro et in vivo." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCD041/document.
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Une présence en excès d'espèces réactives oxygénées induit un déséquilibre redox cellulaire pouvant conduire à des pathologies liées au stress oxydatif, notamment les pathologies cardiovasculaires. Connue et étudiée pour ses propriétés antioxydantes, l’astaxanthine, molécule de la famille des caroténoïdes, présente un intérêt thérapeutique potentiel. Cependant, sa structure chimique lui confère un caractère hydrophobe ainsi qu’une sensibilité à l’air, à la lumière et à la chaleur. Dans cette thèse, tout d’abord, un système de complexation de l’astaxanthine avec l’hydroxypropyl-b-cyclodextrine a été élaboré (CD-A). Nous démontrons que cette complexation améliore la stabilité de l’astaxanthine en solution aqueuse tout en préservant ses activités antioxydantes, mesurées par des méthodes chimiques et biologiques. L’action du CD-A semble être médiée par les voies de signalisation PTEN/AKT, Nrf2/OH1/NQO1 dans des cellules endothéliales soumises au stress oxydatif. Puis, afin de libérer l’astaxanthine in situ sur le site du stress, nous avons élaboré deux systèmes de type matriciel en PVA/dextrane ou en pullulane/dextrane chargés en CD-A. Nous avons évalué, comme preuve de concept, la faisabilité de ces dispositifs pour le traitement local de la pathologie d’ischémie/reperfusion. Les patchs de PVA/dextrane/CD-A ont montré une bonne compatibilité in vitro, ainsi qu’une grande stabilité et tenue mécanique sans modification des propriétés antioxydantes. Leur biocompatibilité in vivo et suturabilité au muscle cardiaque ont aussi été étudiées. Le deuxième système à base de pullulane/dextrane/CD-A a été évalué in vitro et in vivo dans un modèle d’ischémie/reperfusion du membre inférieur à différentes périodes d'implantation. Les résultats ont montré l’activation d’un mécanisme de défense normal lié à la présence d’un matériel étranger et une diminution de la translocation du Nrf2 pouvant indiquer un effet protecteur dans les tissus traités par le CD-A. Ce manuscrit présente des arguments en faveur du potentiel thérapeutique de systèmes de libération d’astaxanthine agissant au niveau du stress oxydatif lié aux pathologies cardiovasculairesAn over concentration of reactive oxygen species induces a redox imbalance within the cell inducing oxidative tissue damage and leading to oxidative stress related diseases, particularly cardiovascular pathologies. Astaxanthin, a well-known and studied antioxidant molecule, member of the xanthophyll carotenoid family, presents an important therapeutic potential. However, the chemical structure confers to astaxanthin a hydrophobic character and renders it susceptible to air, light and temperate degradation. During this thesis, a carrier system based on astaxanthin inclusion within hydroxypropyl-β-cyclodextrin(CD-A) was developed. We demonstrate that after astaxanthin inclusion, not only its stability was enhanced by also the antioxidant scavenging capabilities were preserved, confirmed by chemical and biological tests. The action of CD-A seems to be mediated by PTEN/AKT, Nrf2/OH1/NQO1 signaling pathways of endothelial cells submitted to oxidative stress. Then, two systems based on PVA/dextran and Pullulan/Dextran loaded within CD-A were evaluated for astaxanthin in situ delivery in the stressed environment. The feasibility of using these systems in the local treatment of ischemia/reperfusion injury was evaluated as a proof of concept. PVA/Dextran patches showed good in vitro compatibility, high mechanical and stability properties, while preserving CD-A antioxidant capabilities, also the path suturability to the cardiac muscle and the in vivo biocompatibility were studied. The second system based on pullulan/dextran scaffolds were evaluated in vitro and in vivo in an ischemic/reperfusion model at different implantation periods. Results showed an inner body defense mechanism to foreign materials. Additionally, the Nrf2 translocation could indicate a protective effect of CD-A in treated tissues. This manuscript provides a support evidence of the therapeutic potential of CD astaxanthin delivery system, to act against oxidative stress linked to cardiovascular conditions
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Xu, Simin, and 徐思敏. "Characterization of astaxanthin accumulation in green algae." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43278553.
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Xu, Simin. "Characterization of astaxanthin accumulation in green algae." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43278553.
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Bertolo, Adilson Luís. "Avaliação de um processo de extração e recuperação dos carotenóides presentes no resíduo da industrialização do camarão-rosa (Farfantepenaeus paulensis)." reponame:Repositório Institucional da FURG, 2007. http://repositorio.furg.br/handle/1/3515.
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Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2007.Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-09-25T22:01:19Z No. of bitstreams: 1 avaliao de um processo de extrao e recuperao dos carotenides presentes no resduo da industrializao do camaro-rosa farfantepenaeus paulensis.pdf: 1948791 bytes, checksum: 9ef49c6fc9309bc36c75d41139143d07 (MD5)
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A astaxantina é um carotenóide da classe das xantofilas, amplamente distribuída em animais marinhos e aquáticos, sendo muito utilizada em formulações para aqüicultura e por suas propriedades antioxidantes, podendo também ser utilizada como corante alimentício por sua coloração avermelhada. Este carotenóide pode ser extraído de algas, bactérias e também de crustáceos como o camarão-rosa. Este crustáceo é amplamente capturado na região sul do Rio Grande do Sul, sendo que seu processamento gera mais de 60% de resíduos. O aproveitamento destes resíduos surge como uma alternativa a problemas de impacto ambiental, oriundos do seu despejo na lagoa dos Patos, bem como uma fonte alternativa de recursos para as indústrias e pescadores locais. Neste contexto, o objetivo deste trabalho foi a obtenção de carotenoproteína, utilizando resíduos provenientes da industrialização do camarãorosa(Farfantepenaeus paulensis) por meio de hidrólise enzimática com adição da enzima proteolítica Flavourzyme, e a partir dela, a purificação química da astaxantina, visando avaliar quais variáveis do processo possuíam efeito significativo, e depois de obtido o extrato, foi estudada sua estabilidade frente à luz e temperatura, utilizando astaxantina dissolvida em óleo de soja, como oleoresina. Para analisar quais as variáveis que realmente influenciam no processo de obtenção da carotenoproteína, optou-se pela utilização do planejamento experimental saturado 23 com três pontos centrais, onde se têm três variáveis independentes em dois níveis: tempo (2 e 3 h), temperatura (40 e 50ºC) e concentração de enzima/substrato (0,1 e 0,3%); e como variáveis dependentes: rendimento, porcentagem de proteína e de lipídios. As condições ótimas para o processamento foram: tempo de hidrolise de 2 horas, temperatura de hidrólise de 50°C e concentração de Enzima/Substrato de 0,3%, obtendo um rendimento do processo 9,4% , um teor de proteínas de 70,9% e teor de lipídios de 1,6%. Já para o processo de purificação química da carotenoproteína também foi utilizado um planejamento experimental quadrático completo do tipo 23, com três variáveis independentes em dois níveis, sendo elas: tempo de extração (80 e 280 min), temperatura de extração (26,6 e 43,4°C) e proporção de hexano/ acetona (8 e 92%) e como variáveis dependentes a concentração de astaxantina com três pontos centrais e dois axiais, sendo que com um tempo de extração química de 120 mim, temperatura de extração de 30 °C e com uma proporção de Hexano e Acetona de 25% foi obtida a maior concentração de astaxantina que foi de 197,41 ppm.15. Finalmente foi estudada a estabilidade da oleoresina frente ao calor, apresentando-se estável durante as 8 primeiras horas de exposição à temperatura de 105°C. Já na estabilidade frente à luz, a oleoresina mostrou-se estável por um período de 7 dias.
The Astaxanthin is a carotenoide of the xanthophylls class, widely distributed in marine and aquatic animals, and is often used in formulations for aquaculture and for their antioxidant properties and may also be used as food coloring on its reddish color. Astaxanthin can be extracted of seaweed, bacteria and also of crustaceans as the pink-shrimp. The pink-shrimp is amply captured in the southern region of Rio Grande do Sul, where their processing generates more than 60% of waste. The use of such waste emerges as an alternative to problems of the environmental impact of their eviction from the Pato´s lagoon, as well as an alternative source of resources for industries and local fishermen. In this context, the aim of this study is the obtainment of carotenoprotein using wastes from pink-shrimp processing (Farfantepenaeus Paulensis) through the proteolitic enzyme Flavourzyme, and its chemical purification, aiming to evaluate which of the process variables have significant effects. Once obtained the extract, its stability was studied faced to light and temperature, using astaxanthin dissolved in soy resin oil. To analyze the variables that really influenced the process of carotenoprotein obtainment, it was used an experimental design saturated 23, with three independent variables in two levels: time (2 and 3h), temperature (40 and 50°C) and concentration enzyme/substrate (0.1 and 0.3%) and as dependent variables the yield, lipids and proteins percentage, with three central points. The best conditions for processing were hidrolysys time of 2 hours and 50ºC of temperature, concentration enzyme/substrate of 0.3%, and the yield obtained on the process was 9.4%, protein level of 70,9% and lipids of 1.6%. To the process of chemical purification of the carotenoprotein it was also used an experimental design saturated 23, with three independent variables in two levels: time of extraction (80 and 280 minutes), temperature of chemical extraction (26,6 and 43,4°C) and hexane and acetone proportion (8 and 92%) and as dependent variable the astaxanthin concentration, with three central points and two axial points considering 16 an chemical extraction time of 120 minutes, extraction temperature of 30ºC and hexane and acetone in a 25% proportion the highest astaxanthin concentration gained was 197,41 ppm. Finally the stability of the resin oil faced to heat was studied, presenting stable during the 8 early hours of exposure to temperature of 105ºC. Faced to light, the oil resin became stable during 7 days.
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Dermiki, Maria. "Recovery of astaxanthin using colloidal gas aphrons (CGA)." Thesis, University of Reading, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500537.
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劉愛霞 and Oi-ha Lau. "The growth and astaxanthin formation of haematococcus lacustris." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31215488.
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Grant, Stephanie Mary. "Production of astaxanthin by the yeast Phaffia rhodozyma." Thesis, Queen's University Belfast, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324833.
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Lau, Oi-ha. "The growth and astaxanthin formation of haematococcus lacustris." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19738195.
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Obalil, Jiří. "Miniaturizované techniky pro analýzu průmyslových kvasinek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216334.
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Carotenoids are natural pigments that have antioxidation and antimutagenic abilities. They are produced with the help of new technological methods. For example, carotenoid yeast Rhodotorula glutinis produces -carotene with the yield of up to 6 – 10 mg/g of the dry substance. The method of the mass spectrometry with the nanoelectrospray in the positive mode was optimized for the determination of -carotene, lycopene and astaxanthin in this project. Ionizing voltage of 4 kV and the sample flow rate of 15 – 80 nl/min through the spray silica fused capillary with the internal diameter of 25 µm were found to be the optimum parameters of the analysis. A mixture of chloroform with the addition of ammonia was used as a spray solvent for both standard and cellular samples. During the process of ionization by nanoelectrospray, -carotene and lycopene form cation radical [M] • + with the molecular mass to charge ratio (m/z) of 536, while asthaxanthin forms the protonated molecule [M + H]+ with the m/z of 597. The partial lysis of individual Rhodotorula glutinis cells was demonstrated under microscope in the organic solvents tetrahydrofuran and dimethylsulfoxide. Chloroform, acetone, acetonitrille, methanol and isopropanol did not affect the cells after a 15 min treatment.
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Bowen, Joanne Clare. "Use of microalgal astaxanthin as a pigmentor in aquaculture." Thesis, Liverpool John Moores University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521748.
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Gori, Virginia. "Production and Recovery of Astaxanthin from the Microalga Haematococcus pluvialis." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/19829/.
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Attualmente si sta diffondendo un grande interesse per l’uso nutraceutico e cosmetico dell'astaxantina naturale derivante dalla microalga Haematococcus pluvialis. L'astaxantina è un cheto-carotenoide secondario che tende ad accumularsi quando H. pluvialis è soggetta a condizioni di stress ed è un potente antiossidante. La presente tesi riguarda la produzione ed estrazione di astaxantina mediante metodi innovativi e sostenibili. L'acido ascorbico è stato il miglior fattore di stress che, in aggiunta ad una forte radiazione solare e carenza di nutrienti, ha favorito l'accumulo di astaxantina. Olio di mandorle e NaDES idrofobici a base di terpeni sono stati selezionati come candidati per ottenere formulati arricchiti in astaxantina direttamente disponibili per il consumo umano o per l'industria cosmetica; tutti i solventi sono stati testati attraverso il test di milking per mantenere in vita la coltura cellulare. In termini di vitalità cellulare, il miglior NaDES è stato il mentolo: acido oleico, seguito da α-bisabololo, mentolo: acido laurico e timolo: acido oleico; tuttavia il tasso di recupero di astaxantina è stato molto basso. L’olio di mandorle invece ha consentito il raggiungimento di un buon compromesso tra tasso di vitalità e di recupero. Entrambi i solventi hanno consentito di ricoltivare la coltura algale dopo una prima estrazione con approccio milking, senza compromettere la transizione cellulare dalla fase di stress a quella vegetativa. Questo fenomeno rende il processo di estrazione sostenibile riducendo i costi energetici ed economici associati alla perdita di biomassa algale. Nella seconda parte della tesi sono stati studiati gli effetti dell'astaxantina naturale e sintetica sulle cellule cancerogene Hep G2. I risultati dei test hanno dimostrato che sia l'astaxantina naturale che quella sintetica sono potenti antiossidanti; tuttavia solo l’astaxantina sintetica sembra avere un effetto sul metabolismo lipidico e sulla respirazione mitocondriale.
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Scaife, Mark Aden. "Metabolic engineering of Escherichia coli for the biosynthesis of astaxanthin." Thesis, University of Sheffield, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.489874.
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Carotenoids hold great promise due to their numerous health promoting properties. Of the plethora of carotenoids isolated, astaxanthin is one of the most intensively investigated. Astaxanthin can be synthesised by a number of organisms, however these are often not amenable to current industrial production methods, and those that are produce low or impure yields. In this thesis, data are presented' regarding the development of an Escherichia coli based astaxanthin production system that is able to rapidly accumulate industrially relevant quantities of highly pure astaxanthin. In pursuit of this, the genomes of five cyanobacterial strains are screened in order to identify putative genes involved in the final stages of astaxanthin biosynthesis, specifically in the conversion of f3-carotene to astaxanthin. Subsequently the sixteen putative genes identified are functionally characterised, via co-expression in E. coli, and investigated with respect to their capacity to function in astaxanthin biosynthesis. This reveals that all twelve f3-carotene ketolase genes identified are functional, as are two of the four f3-carotene hydroxylase genes. However, only the CrtW type f3. carotene ketolase genes are able to participate in astaxanthin biosynthesis. The best performing elements, with respect to astaxanthin biosynthesis, are combined and employed in the creation of a number of E. coli based astaxanthin production strains. Subsequent studies focus on metabolic restrictions within this system, employing heterologous gene expression and directed evolution methods, as well as a novel PCR based cloning method, in the creation of an E. coli production strain capable of the synthesis of 4.7 mg L-1 astaxanthin in a 24 hour period, at> 90% purity. Further, this study identifies a range of restrictions within the system, and presents methods by which future work could negotiate these, allowing the development of an industrially competitive production strain.
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Ip, Po-fung, and 葉寶鳳. "Elicitation of astaxanthin biosynthesis in dark-heterotrophic culturesof Chlorella zofingiensis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B34617048.
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Matumba, Tshifhiwa Given. "Role and distribution of astaxanthin in spiny lobster, Jasus lalandii." Master's thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/6133.
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The occurance and distribution of astaxanthin in tissues of the spiny lobster, Jasus lalandii was investigated. The concentration of astaxanthin was quantified in the exoskeleton, haemolymph, muscles, gonads and hepatopancreas as well as in egg parcels from berried females during the moult as well as the reproductive cycles. Astaxanthin was the dominant carotenoid in all tissues, but small amounts of other carotenoids were detected. Exoskeleton, ovaries and extrude egg parcels had significantly higher astaxanthin concentration than haemolymp, muscles and hepatopancreas. This distribution of astaxanthin was found in both captive and free-living spiny lobsters. Free-living spiny lobsters generally had higher astaxanthin concentration than the captive spiny lobsters although the data is not statistically significant in all tissues investigated.
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Karuppuswamy, Renuka Chemical Sciences & Engineering Faculty of Engineering UNSW. "Extraction and characterization of major valuable compounds from prawn waste." Publisher:University of New South Wales. Chemical Sciences & Engineering, 2008. http://handle.unsw.edu.au/1959.4/43329.
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Most prawns are prepared as frozen or canned meat and the remaining waste is used as a feed supplement or directly disposed on to the land, which affects the environment. Fresh prawn bio-waste contains protein, astaxanthin, flavor compounds and chitin. The use of chitin in various applications is limited due to its water insolubility. In this research, a new method is developed to prepare water-soluble colloidal chitin (WSCC) from prawn waste. WSCC having the percentage of degree of deacetylation same with that of chitin follows non-newtonian shear thinning behaviour. The characteristic study showed that the breakage of polymer chains during processing thus reduced the molecular weight and bulk density of WSCC. Therefore, functional properties of WSCC can be controlled by optimizing the processing conditions. Astaxanthin complex has attracted considerable interest in relation to its health benefits because of its powerful antioxidant activity. Traditional extraction of astaxanthin complex from prawn waste using organic solvents requires post-purification steps, creates solvent disposal problem and degrades the pigment. This research develops an efficient way of recovering astaxanthin complex from prawn waste that eliminates the problems associated with solvent extraction methods and offers possible recyclability of the solvents used. Post-harvest blackening in prawns adversely affects both quality and consumer acceptability. However, consumer safety over the chemicals, especially sulphites used in inhibiting prawn blackening is of a major concern. This study shows that the antioxidant, astaxanthin complex can inhibit the poly phenol oxidase (PPO) catalyzed blackening reaction in prawns. Although prawns have astaxanthin complex present in their natural state, its concentration in vivo may not be sufficient to act against PPO. Therefore, astaxanthin complex-enriched feed in prawn culture may prevent prawn melanosis and may eliminate the post-harvest handling methods.
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Steinbrenner, Jens. "Regulation der Astaxanthinbiosynthese in der Grünalge Haematococcus pluvialis." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:352-opus-50787.
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Ip, Po-fung. "Elicitation of astaxanthin biosynthesis in dark-heterotrophic cultures of Chlorella zofingiensis." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B34617048.
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Guo, Jingfei. "Crystallization of polymorphs a case study on astaxanthin and apocarotenoic ester." Aachen Shaker, 2009. http://d-nb.info/99883551X/04.
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Silveira, Aline Alves Barbosa da. "Produção de astaxantina por Mucor javanicus (UCP 69), a partir de meio definido e utilizando resíduo industrial (milhocina e quirera de milho)." Universidade Católica de Pernambuco, 2007. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=169.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCom a recente substituição dos pigmentos sintéticos pelos carotenóides naturais, pesquisas têm sido desenvolvidas para viabilizar uma maior produção destas substâncias, através de fontes biológicas alternativas. Neste trabalho foi estudada a produção de astaxantina por uma amostra de Mucor javanicus utilizando o meio definido Hesseltine e Anderson (1957) modificado por Andrade (2000) e meios utilizando resíduos de milho (milhocina e quirera), em concentrações distintas (4%, 7% e 10%), pH 6,5, 120 rpm, 25C. Foram analisada também a influência do tempo de cultivo da amostra durante 48h, 72h e 96h, na presença e ausência de luz azul. Ao término do processo fermentativo, a astaxantina foi extraída em solução de Hexano/metanol e analisada por espectroscopia UV- visível (470 nm). Todos os parâmetros estudados nos experimentos foram combinados através de um planejamento fatorial 33 e analisados no Software Statistica 5.0. No meio Hesseltine e Anderson o melhor rendimento de astaxantina foi verificado no tempo de 96h (26,7 g/g), na ausência de luz e quando se utilizou luz azul (37,7 g/g), obteve-se um aumento de 41%. A melhor condição para a produção da astaxantina com a milhocina deu-se na concentração de 4%, 96h, com luz (55,8 g/g), aumentando em quase 100%, quando comparada com as culturas crescidas na ausência de luz (28,0 g/g). A quirera na concentração de 7% apresentou melhor rendimento de astaxantina, no tempo de 96h, com luz (18,4 g/g), aumentando 37%, quando comparada com as culturas crescidas na ausência de luz (13,4 g/g). O melhor rendimento de astaxantina com milhocina e quirera deu-se na concentração de 7%, 96h, com luz (33,8 g/g), aumentando em quase 47%, quando comparada com as culturas crescidas na ausência de luz (22,9 g/g). As concentrações que mais favoreceram ao aumento do rendimento da astaxantina foram: milhocina 4%, quirera 4% e milhocina com quirera 7%, todos na presença de luz azul, demonstrando que a luz azul interfere diretamente na síntese de astaxantina. Bem como que os resíduos utilizados possuem potencial para a produção de astaxantina. As análises no Statistica 5.0, demonstram a necessidade da realização de outros estudos para obtenção da produtividade máxima de astaxantina por M. javanicus, nos meios alternativos.
With the recent substitution of synthetic pigments for the natural carotenoids, research has been effected in the direction to make possible the production of these substances through alternative considered biological sources. In this work was studied the production of astaxanthin for the sample of Mucor javanicus (CPU - 69), using the media definite Hesseltine and Anderson (1957) modified by Andrade (2000) and using different corn waste media (corn steep liquor .CSL and .quirera.) in three different concentrations (4, 7 and 10%), pH 6,5, 120 rpm, 25C. It was analyzed, also, the influence of the time of culture of the sample (48h, 72h and 96 h) and the presence and absence of blue Light. To the ending of the fermentative process, the astaxanthin, was extracted in solution of Hexano/methanol (1: 1, v/v), centrifuged in 2000 rpm/10 minutes and analyzed by UV-visible spectrophotometry (470 nm). All the parameters studied in the experiments had been combined through a factorial design 33 and analyzed in Software Statistica 5,0. With Hesseltine and Anderson the condition that more favored the increase of the income of the astaxanthin was with in the time of 96h (26,7 g/g) in the absence of light and with the presence of light (37,7 g/g) increase almost 41%. With CSL the best condition for the production of the astaxanthin was with in the time of 96h (55,8 g/g) in the absence of light and with the presence of light (28,0 g/g) increase almost 100%. The .quirera. in the concentration of 7%, presented astaxanthin income better, in the time of 96h, with light (18,4 g/g) increase 37%, when compared with the cultures growth in the absence of light (13,4 g/g). The best income of astaxanthin with CLS and .quirera. was in the concentration of 7%, 96h, with light (33,8 g/g), increase almost 47% in when compared with the cultures growth in the absence of light (22,9 g/g). The concentrations that more favored the income of astaxanthin was: CSL 4%, .quirera. 7% and CSL with .quirera. 7%, both in the presence of blue light, demonstrate the blue light intervenes directly with the astaxanthin synthesis. Also, the wastes utilizes have been potential for the astaxanthin production. The analyses in Statistica 5,0, demonstrate that other studies are necessary for attainment of the maximum productivity of astaxanthin for M. javanicus,
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Page, Gregory Ian. "Physiological and biochemical factors affecting carotenoid utilization in salmonid fish." Thesis, University of Plymouth, 2001. http://hdl.handle.net/10026.1/2383.
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Carotenoid utilization in rainbow trout (Oncorhynchus mykiss Walbaum) and Atlantic salmon (Salmo salar L.) has been investigated with respect to tissue distribution of carotenoids and the role of the liver on the bioavailability of the lipid soluble carotenoids, astaxanthin and canthaxanthin. Species-specific and tissue-specific accumulations were noted for astaxanthin and canthaxanthin in the rainbow trout and Atlantic salmon, possibly indicating fundamental differences in their utilization in these species. The liver and the kidney were revealed to be the major tissues involved in carotenoid metabolism in both rainbow trout and Atlantic salmon. Apparent digestibilities (-96% and -30% for rainbow trout and Atlantic salmon, respectively) and flesh carotenoid retentions (-12% and -5.4% for rainbow trout and Atlantic salmon, respectively) differed significantly between species, suggesting that rainbow trout are more efficient depositors of carotenoids within the flesh. Isolated rainbow trout liver perfusion experiments revealed small differences in the uptake of astaxanthin and canthaxanthin. Uptake of astaxanthin in both synthetically-derived and serum-derived models showed saturable uptake mechanism that occurred earlier than for canthaxanthin. These results can potentially offer an explanation for the better utilization of astaxanthin in rainbow trout, where the liver reduces the bioavailability of canthaxanthin through continued uptake. Results show a low hepatic extraction ratio (0.03-0.07), in line with published post-prandial elimination rates. Neither astaxanthin nor canthaxanthin significantly induced hepatic or renal xenobiotic-metabolizing enzymes in the rainbow trout, contrary to published reports in rats and mice. This may imply fundamental species-specific differences in the metabolic pathways for these carotenoids. Histochemical investigations revealed that both carotenoids significantly impacted liver structure, resulting in higher levels of total lipids and mucopolysaccharides. This is thought to be due to their antioxidant functions and their provitamin A activity. Carotenoid-treated fish also had higher levels of glycogen phosphorylase in liver sections, providing the first evidence in fish for the possibility of glucuronidation of their metabolites. The present investigations demonstrate the liver to be a major organ in carotenoid metabolism, and consequently affects carotenoid distribution and availability. In addition, carotenoid supplementation significantly affects liver structure and may potentially enhance its function. Furthermore, these investigations have provided new avenues of investigation into the use of isolated organ perfusions for biochemical nutrition research, and expanded the knowledge of liver physiology and biochemistry.
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Pertig, Dan [Verfasser]. "Crystallization of Isomeric Compounds : On the multiple facets of Astaxanthin / Dan Pertig." Aachen : Shaker, 2013. http://d-nb.info/1051573602/34.
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Bergvik, Maria. "Lipid and Astaxanthin Contents and Biochemical Post-Harvest Stability in Calanus finmarchicus." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16971.
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龔賢弟 and Xiandi Gong. "Optimisation and modelling of the growth and astaxanthin formation of haematococcus pluvialis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B3123690X.
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White, Daniel Allan. "Absorption and utilisation of natural and synthetic astaxanthin forms in salmonid nutrition." Thesis, University of Plymouth, 2001. http://hdl.handle.net/10026.1/2297.
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Consumer preference for commercially reared fish products that resemble their wild counterparts has resulted in the supplementation of pigments called carotenoids into aquafeeds to promote a pink-red colour in the flesh of salmonid fish. To date synthetic forms of these pigments have been commonly utilised to achieve this desired colouration, with the carotenoid astaxanthin being the regular choice for the feed manufacturer. However, increase in consumer demand for farmed fish products reared on natural feed additives has evoked an interest in natural sources of astaxanthin that could be successfully used to pigment salmonid fish efficiently. In the current study, the microalga Haemalococcus pluvialis has been assessed as a potential feed supplement to pigment the flesh of rainbow trout (Oncorhynchus mykiss). More specifically, those natural characteristics that may well limit the absorption and utilisation of astaxanthin from this source have been assessed individually and discussed from a physiological standpoint. The cell wall of Haemalococcus pluvialis when cracked efficiently presents no limitation to the absorption and utilisation of astaxanthin from this source. Indeed, the cell wall remnants help to prevent oxidation of astaxanthin in the feed compared to cell wall free extracts of carotenoid from the same source. However, esterified astaxanthin (which this algae predominantly contains) is not absorbed as efficiently as unesterified synthetic astaxanthin. Furthermore, the extent of esterification is negatively related to the absorption of astaxanthin. Regional variation in ester hydrolysis along the gastrointestinal tract combined with gut transit time of the ingested feed may explain these limitations. However, despite limitations in absorption, the muscle deposition of astaxanthin supplied as esters does not significantly differ from the unesterified form. The optical purity of astaxanthin esters from this source does not prejudice the final deposition of astaxanthin in fish tissues. An in vitro model has been developed to assess the absorption of astaxanthin at the intestinal level in salmonid fish in order to define absorption characteristics of carotenoids under different abiotic and biotic conditions. The absorption of astaxanthin seems to occur in a linear passive manner into the intestinal tissue. Although size of the fish does not affect the absorption of astaxanthin, temperature does have a significant effect. Although there were no significant differences in absorption between Atlantic salmon (Salmo salar) and rainbow trout, absorption tended to be greater in the latter species and merits further study.
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Prazeres, Inês. "Development of astaxanthin lipid formulations for nutraceutical application: targeting the gastrointestinal epithelium." Master's thesis, Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica António Xavier, 2019. http://hdl.handle.net/10362/130075.
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Dissertation presented to obtain the Master degree in Biochemistry for Health"Astaxanthin is renowned for its powerful antioxidant activity and remarkable therapeutic effects in the prevention and treatment of several diseases. Moreover, astaxanthin could constitute a potential nutraceutical to be used in the treatment and maintenance of Inflammatory Bowel Diseases. However, its therapeutic use is seriously limited by its instability and low bioavailability. Hence, in this work, astaxanthin and a shrimp shells extract rich in astaxanthin were entrapped into nanostructured lipid carriers (NLCs) and structured lipid carriers (SLCs). Furthermore, their permeability was assessed in a Caco-2 monoculture and in a Caco-2:HT29-MTX:Raji-B triple co-culture. Additionally, their capacity to inhibit reactive species of oxygen (ROS) formation was assessed in Caco-2 monolayers.(...)"
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Gong, Xiandi. "Optimisation and modelling of the growth and astaxanthin formation of haematococcus pluvialis /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19003390.
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Grimmig, Beth. "Astaxanthin Attenuates MPTP Induced Neurotoxicity and Modulates Cognitive Function in Aged Mice." Scholar Commons, 2017. https://scholarcommons.usf.edu/etd/7405.
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Parkinson’s disease is the second common neurodegenerative disease and is most frequently diagnosed in individuals over 60. There are no available medications that can prevent or restore the loss of neurons that correspond to motor impairments in patients. Identifying novel therapeutic compounds that are capable of slowing and reversing the extensive neurodegeneration that occurs in PD remains an important goal of the field. While basic research has identified potential therapeutic agents, studies often use young model organisms to demonstrate efficacy of the target compound. This approach ignores the impact of the aged CNS on the disease process, and likely contributes to high failure rates of translation in clinical trials. Here we investigate the capacity for astaxanthin (AXT), a xanthophyll carotenoid, to attenuate the neurotoxicity to MPTP, a toxin routinely used to establish parkinsonian symptoms in mice. We show that AXT reduces MPTP induced neurotoxicity in young, but less effective in the aged animals. While AXT is an interesting neuroprotective capacity, there are also multiple reports that indicate AXT may preserve cognitive function in the context of neurodegeneration and neural injury, the impact of AXT under physiological conditions and in the aged CNS has been largely uninvestigated. We also evaluate the effect of AXT on cognitive function in young and aged mice. Here, we show that AXT supplementation can modulate neural plasticity is associated with improved performance in cognitive behavioral tasks. This diet effect was observed in both young and aged mice, suggesting a novel and direct mechanism of action in synaptic function.
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Daubrawa, Felicitas Ulrike. "Effekte von Astaxanthin und Canthaxanthin auf die Zell-Zell-Kommunikation über Gap Junctions." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=979445736.
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Seabra, Larissa Mont Alverne Juca. "Camar?o Litopenaeus vannamei: componentes de import?ncia nutricional na carne e nos res?duos do beneficiamento." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13239.
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Previous issue date: 2011-11-23Universidade Federal do Rio Grande do Norte
Farming of marine shrimp is growing worldwide and the Litopenaeus vannamei (L. vannamei) shrimp is the species most widely cultivated. Shrimp is an attractive food for its nutritional value and sensory aspects, being essential the maintenance of this attributes throughout storage, which takes place largely under freezing. The aim of this research was to evaluate quality characteristics of Litopenaeus vannamei shrimp, during freezing storage and to verify the effect of rosemary (Rosmarinus officinalis) adding. Considering the reutilization of processing shrimp wastes, total carotenoids analysis were conducted in waste of Litopenaeus vannamei shrimp and in the flour obtained after dryer. Monthly physicochemical and sensorial analysis were carried out on shrimp stored at 28,3 ? 3,8?C for 180 days. Samples were placed in polyethylene bags and were categorized as whole shrimp (WS), peeled shrimp (PS), and PS with 0,5% dehydrated rosemary (RS). TBARS, pH, total carotenoid and sensorial Quantitative Descriptive Analysis (QDA) were carried out. Carotenoid total analysis was conducted in fresh wastes and processed flour (0 day) and after 60, 120 and 180 days of frozen storage. After 180 days, RS had lower pH (p = 0.001) and TBARS (p = 0.001) values and higher carotenoids (p = 0.003), while WS showed higher carotenoid losses. Sensory analysis showed that WS were firmer although rancid taste and smell were perceived with greater intensity (p = 0.001). Rancid taste was detected in RS only at 120 days at significantly lower intensity (p = 0.001) than WS and PS. Fresh wastes had 42.74μg/g of total carotenoids and processed flour 98.51μg/g. After 180 days of frozen storage, total carotenoids were significantly lower than 0 day (p<0,05). The addition of rosemary can improve sensory quality of frozen shrimp and reduce nutritional losses during storage. Shrimp wastes and flour of L. vannamei shrimp showed considerable astaxanthin content however, during storage it was observed losses in this pigment
O cultivo do camar?o marinho cresce mundialmente, sendo o Litopenaeus vannamei (L. vannamei), a esp?cie mais cultivada na atualidade. O camar?o ? um alimento atrativo por seu valor nutricional e aspectos sensoriais, sendo essencial, a manuten??o desses atributos ao longo do armazenamento. Os objetivos da presente pesquisa foram avaliar caracter?sticas de qualidade do camar?o L. vannamei adicionado de alecrim (Rosmarinus officinalis) e armazenado sob congelamento, assim como realizar a determina??o da concentra??o de caroten?ides totais dos res?duos do camar?o e da farinha obtida ap?s secagem. As amostras foram colocadas em embalagens de polietileno e estocadas como Camar?o Inteiro (CI), Camar?o Descascado (CD) e Camar?o descascado adicionado de 0,5% de alecrim desidratado (CA). An?lises de TBARS, pH e caroten?ides totais foram realizadas, assim como an?lise sensorial utilizando An?lise Descritiva Quantitativa (ADQ). As an?lises f?sico-qu?micas e sensoriais do camar?o L. vannamei armazenado sob congelamento (-28,3?3,8?C), foram realizadas mensalmente, por um per?odo de 180 dias. Com rela??o ?s an?lises dos res?duos, estas foram realizadas no material in natura e na farinha rec?m-processada (dia 0) e aos 60, 120 e 180 dias de armazenamento sob congelamento. No final do per?odo de armazenamento CA apresentou menor pH (p = 0,001) e valores de TBARS (p = 0,001) e concentra??o mais alta de caroten?ides totais (p = 0,003), enquanto CI demonstrou maior perda de caroten?ides. A an?lise sensorial mostrou maior firmeza para CI, por?m estas amostras apresentaram sabor e cheiro de ran?o em maior intensidade (p = 0,001). Os provadores perceberam sabor de ran?o nas amostras CA apenas aos 120 dias de armazenamento, e em menor intensidade do que nas amostras de CI e CD (p = 0,001). No que se refere ?s an?lises dos res?duos, observou-se concentra??o de 42,74μg/g de caroten?ides totais nos res?duos frescos e 98,51μg/g na farinha rec?m-processada. Ap?s 180 dias de armazenamento sob congelamento, os teores de caroten?ides totais diminu?ram significativamente quando comparados ao dia 0 (p<0,05). A adi??o de alecrim pode melhorar a qualidade sensorial do camar?o congelado e reduzir perdas de seu valor nutricional ao longo do armazenamento sob congelamento. Os res?duos e a farinha do camar?o L. vannamei, apresentaram concentra??o consider?vel de astaxantina, que foi reduzida ao longo do congelamento
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Lin, Shujun. "Effect of dietary lipid and astaxanthin level on pigmentation of Arctic charr (Salvelinus alpinus)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ36146.pdf.
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袁建平 and Jianping Yuan. "Characteristics and chromatographic separation of astaxanthin and its esters from the microalga haematococcus pluvialis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31239717.
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Suen, Yung-lee, and 孫蓉莉. "Expression of vitreoscilla hemoglobin in Aurantiochytrium sp. enhancesthe production of fatty acids and astaxanthin." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50533940.
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Heterotrophic fermentation is a widely used means in the biotechnological, pharmaceutical and food industries for the large-scale production of desired products. However, two problems are often encountered during its application: the limitation of dissolved oxygen level in high cell density cultures, and the high cost of the carbon substrates for supporting growth. In this study these issues are solved through the expression of the hemoglobin gene from Vitreoscilla (VHb), which is known to be able to facilitate intracellular oxygen delivery, and the use of low-cost waste carbon sources for fermentation, respectively. Aurantiochytrium sp. MP4 (non-pigmented) and SK4 (pigmented) were chosen for the present study because of members of this genus has been consideredas potential producers of biodiesel as well asastaxanthin in recent years.
VHb gene was successfully expressed in Aurantiochytrium sp. MP4 and SK4, and three transformants of MP4 (TMP4-VHb1, TMP4-VHb10 and TMP4-VHb24) and one transformant of SK4 (TSK4-VHb2) were obtained, respectively. TMP4-VHb24 andTSK4-VHb2 were selected for further study. It was found that VHb expression led to higher maximum biomass under microaerobic conditions and improved oxygen utilization in high cell density fermentation. Moreover, under aerobic conditions, there was an increase of total cellular fatty acid content by 10% and 44%forTMP4-VHb24 and TSK4-VHb2,respectively, and the pigmented strain TSK4-VHb2 produced 9-fold higher astaxanthin content than the control (i.e., SK4), showing that heterologous expression of VHb as a promising approach to improving growth or secondary metabolite biosynthesis in the fermentation process.
The mechanism underlying the effects of VHb expression was further investigated using TMP4-VHb24. Expression of VHb led to a higher adenylate energy charge and hence higher metabolically available energy in the cells, especially at the late exponential phase. In addition, VHb expression promoted the rate of consumption of NADH during the period from the late exponential phase to the stationary phase, in which NADH carried electrons from the oxidation of carbon substrates in energy pathways for ATP synthesis. VHb also increased the resistance of the host cells to nitrosative stress, but not to oxidative stress.
In terms of utilization of cheap carbon substrates, TMP4-VHb24 and TSK4-VHb2were found to grow well on the waste carbon sources including cane molasses and crude glycerol. Under such conditions, however, the contents of fatty acids and astaxanthin were generally lowered compared to the use of glucose-based media. Therefore, the growth and product synthesis in TMP4-VHb24 was further optimized using the response surface methodology, and it was found to be effective.
In conclusion, the expression of VHb in Aurantiochytrium sp. MP4 and SK4 was effective in relieving limitation on the growth due to low oxygen availability at high cell density cultivation, while increasing the cellular astaxanthin and fatty acid biosyntheses under aerobic conditions. Also, the VHb-expressing strains were able to utilize low-cost waste carbon sources, and the response surface methodology could be employed to optimize fermentation effectively in order to lower the cost of fermentation.published_or_final_version
Biological Sciences
Doctoral
Doctor of Philosophy
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Yuan, Jianping. "Characteristics and chromatographic separation of astaxanthin and its esters from the microalga haematococcus pluvialis /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20792888.
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Papa, Thiago Bueno Ruiz. "Síntese, caracterização e reatividade de antiradicais de dupla função." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/75/75133/tde-18022016-100417/.
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A deterioração oxidativa de alimentos é o fator determinante na qualidade sensorial e nutricional do produto, podendo ocorrer em alimentos complexos tanto na fase contínua como na fase dispersa. Em geral, a formação de radicais e espécies reativas de oxigênio e nitrogênio é o evento primário que ocorre priori ao progresso da oxidação de componentes e estruturas sensíveis e está comumente associado a eventos na fase aquosa. A oxidação de lipídeos é frequentemente investigada em alimentos e em meio biológico separadamente dos eventos no meio aquoso e a proteção antioxidante somente avaliada na fase dispersa. Entretanto, a oxidação de proteínas e eventos na fase contínua vêm despertando considerável interesse e aparentemente antioxidantes eficientes na fase dispersa não protegem de forma eficaz as proteínas e os componentes na fase contínua. Um futuro progresso na proteção antioxidante de alimentos e sistemas biológicos origina de uma abordagem holística dos processos redox envolvidos em ambas as fases dispersa e contínua, bem como o uso combinado de espécies antioxidantes e antiredutoras para um superior efeito antiradical global. Neste sentido, foram preparados três novos compostos antiradicais de dupla função (antioxidante e antiredutor) com adequado balanço hidrofílico-lipofílico e aprimorada propriedade antiradical global. Os antiradicais diferulato de astaxantina, retinoato de quercetina e retinoato de epicatequina se mostraram melhores antioxidantes e antiredutores do que seus precursores isoladamente ou em misturas, apresentando superior eficiência na desativação do oxigênio singlete excitado, captação do radical 1-hidroxietila, menor efeito pró-oxidante em sistemas de oxidação catalisados por íons de ferro, e eficiência na redução do reativo estado triplete da safranina (E1/2 = 1,48 V vs. NHE).The oxidative deterioration of foods is the determining factor in the sensory and nutritional quality of the product, which may occur in complex food both at the continuous and the dispersed phases. In general, the formation of radicals and reactive oxygen and nitrogen species is the primary event that occurs prior to the progress of oxidation of components and sensitive structures and is commonly associated with events in the aqueous phase. The oxidation of lipids is often investigated in food and biological media separately from the events in the aqueous phase and the measurement of the antioxidant protection is only evaluated in the dispersed phase. However, the oxidation of proteins and the events in the continuous phase have attracted considerable interest and apparently, efficient antioxidants in dispersed phase do not effectively protect proteins and components in the continuous phase. A further progress in the antioxidant protection of food and biological systems arise from a holistic approach of the redox processes involved in both the dispersed and continuous phases as well as the combined use of antioxidant and antireductant species for a superior overall antiradical effect. In this sense three new antiradical compounds with dual function (antioxidant and antireductant) were prepared with proper hydrophilic-lipophilic balance and global antiradical properties. The antiradicals astaxanthin diferulate, epicatechin retinoate, and quercetin retinoate are shown to be better antioxidant and antireductant than their precursors, isolated or in mixture, exhibiting enhanced singlet excited oxygen deactivation, 1-hydroxyethyl radical scavenging, lower pro-oxidative effect in the oxidative system catalysed by iron ions and an efficient reduction of the reactive triplet state of safranine (E1 / 2 = 1.48 V vs. NHE).
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De, Bruyn Anneke. "Isolation of potential probiotic and carotenoid producing bacteria and their application in aquaculture." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79852.
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Thesis (MSc)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The ocean’s fish resources are declining mainly because of irresponsible exploitation. Fish is a vital source of protein for humans and growing world populations are threatening the sustainability of commercial fisheries. This has led to the rapid growth of aquaculture worldwide. In South Africa, aquaculture of both fresh and marine species is expanding and is now practised in all nine provinces of the country. One of the major problems in aquaculture is the economic losses as a result of diseases. Viruses, bacteria, fungi and parasites are well known to infect fish, with bacteria causing the majority of diseases. Antibiotics were commonly used to control diseases, however, due to their negative impact on the environment, the use of these agents is questioned. This has led to the search for probiotics as an alternative way to control bacterial diseases in aquaculture. Probiotics used in aquatic environments can be defined as live microbial supplements which have beneficial effects on the host by altering the microbial communities associated with the host and the immediate environment. Probiotics have a variety of different mechanisms of action, including competition with pathogens, production of beneficial compounds, enhancement of host immune response and antiviral effects. This study aimed to isolate potential probiotic bacteria from the gastrointestinal tract (GIT) of the South African abalone (Haliotis midae). Nine different bacterial species were isolated and identified as Corynebacterium variabilei, Staphylococcus carnosus, Staphylococcus equorum, Staphylococcus cohniii, Vibrio aestuarianus, Vibrio nigripulchritudo, Vibrio cyclitrophicus, Photobacterium leiognathi, and Paracoccus marcusii (Chapter 2). One of these isolates, P. marcusii (isolate 6.15), showed promising probiotic properties together with the potential to be used as a pigmentation source due to its production of the carotenoid astaxanthin. Aquatic animals are not able to synthesize astaxanthin and under aquaculture conditions do not come into contact with natural pigment sources. This results in dark grey meat which is unappealing for consumers. Therefore, astaxanthin is included in the feed of a variety of aquaculture species such as salmon, trout, red see bream and shrimp to give the meat a pink/orange colour. Astaxanthin also plays an important role in other essential biological functions of fish such as increasing the defence potential against oxidative stress and enhancing sexual maturity, embryo development, and egg survival. Mozambique tilapia (Oreochromis mossambicus) and rainbow trout (Oncorhynchus mykiss), two important aquaculture species in South Africa, were used to evaluate the probiotic and pigmentation effect of P. marcusii (isolate 6.15). Fish feed was coated with freeze dried bacterial cells (107 CFU/kg feed) and administrated to tilapia and trout. Because tilapia cannot incorporate astaxanthin into their meat, no pigmentation effect of P. marcusii (isolate 6.15) was evaluated for this species. However, tilapia showed significant improvement in growth and immune parameters. Fish supplemented with P. marcusii (isolate 6.15) had a higher percentage increase in body weight and a better feed conversion ratio for the duration of the trial. Enhanced lysozyme activity in the blood serum of the fish was also seen (Chapter 3). In contrast, P. marcusii (isolate 6.15) did not have any probiotic or pigmentation effect on rainbow trout. A possible reason for this may be that the concentration of P. marcusii (isolate 6.15) added to the feed was too low. More probably, it is suspected that no pigmentation was observed due to the destruction of the astaxanthin before being ingested by the trout, because astaxanthin is a very unstable molecule. Furthermore, the GIT microbial communities of trout were investigated over the duration of the trial for the different treatments. No similarities in community structures were observed betwee the different treatments, however, bacterial communities in the GIT of fish sampled at the same time were very similar (Chapter 4).
AFRIKAANSE OPSOMMING: Die oseaan se vis hulpbronne is besig om af te neem as gevolg van die onverantwoordelike gebruik daarvan. Vis is ‘n belangrike bron van proteïene vir mense en die toenemende wêreld populasie bedreig die volhoubaarheid van kommersiële visserye. As gevolg hiervan is daar ‘n drastiese toename in die akwakultuur industrie wêreldwyd. Ook in Suid Afrika brei die akwakultuur van beide vars water en mariene vis spesies uit. Een van die grootste probleme in akwakultuur is ekonomiese verliese as gevolg van siektes wat veroorsaak word deur virusse, bakterieë, fungi en parasiete. Bakterieë veroorsaak die meerderheid van die siektes en antibiotika word algemeen gebruik vir die beheer van bakteriële siektes. Die gebruik van antibiotika word egter bevraagteken omdat dit verskeie negatiewe implikasies vir die omgewing inhou Daarom word probiotika oorweeg as ‘n alternatief tot antibiotika om bakteriële siektes te voorkom en te behandel. Probiotika wat in akwatiese omgewings toegedien word kan gedefinieer word as a lewende mikrobiese aanvulling wat ‘n positiewe effek op die gasheer het, deur die mikrobiese gemeenskappe geassosieer met die gasheer en die ommidellike omgewing te verander. Hierdie mikrobiese aanvulling verbeter die gesondheid van die visse deur verskeie meganismes wat insluit kompetisie met patogene, produksie van voordelige chemiese verbindings, verhoging van die gasheer se immuniteit en antivirale effekte. Die doel van hierdie studie was om potensiële probiotika te isoleer uit die spysverterings kanaal (SVK) van die Suid Afrikaanse perlemoen spesie, Haliotis midae. Tydens die studie is daar nege verskillende bakteriële spesies geïsoleer en geidentifiseer as stamme verteenwoordegend van Corynebacterium variabilei, Staphylococcus carnosus, Staphylococcus equorum, Staphylococcus cohniii, Vibrio aestuarianus, Vibrio nigripulchritudo, Vibrio cyclitrophicus, Photobacterium leiognathi en Paracoccus marcusii (Hoofstuk 2). Een van die isolate, P. marcusii, het belowende probiotika en potensiële pigmentering eienskappe getoon a.g.v. die produksie van die karotenoïed astazantien. Akwatiese diere is nie daartoe instaat om hierdie pigment te produseer nie en onder akwakultuur toestande kom die visse ook nie in kontak met natuurlike bronne van hierdie pigment nie. Dit lei daartoe dat die vleis van visspesies soos forel en salm grys word wat dit onaantreklik vir verbruikers maak. Daarom word astazantien bygevoeg by visvoer om sodoende ‘n pienk/oranje kleur te verseker.Daar benewens speel astazantien ook ‘n rol in belangrike biologiese funksies van visse. Dit sluit in die verhoging in beskerming teen oksidatiewe stres, bevordering van seksuele volwassenheid, embrio ontwikkeling en eier oorlewing. Twee belangrike akwakultuur spesies in Suid Afrika, Mosambiek tilapia (Oreochromis mossambicus) en reënboog forel (Oncorhynchus mykiss), was in hierdie studie gebruik. Die probiotiese en pigmentasie effek van P. marcusii op reënboog forel was gëevalueer terwyl slegs die probiotiese effek op tilapia geëvalueer weens die onvermoeë van tilapia om die pigment in hul vleis te inkorpereer. Visvoer korrels was omhul met gevriesdroogde bakteriële selle (107 CFU/kg kos) en vir die visse gevoer. Daar was ‘n duidelike verbetering in groei en immuun parameters van tilapia. Visse toegedien met P. marcusii het ‘n hoër persentasie vermeerdering in liggaamsgewig en ‘n beter voedsel omsettings verhouding gehad tydens die verloop van die proef in vergelyking met die kontroles (Hoofstuk 3). In kontras hiermee kon daar geen probiotiese of pigmenterings effekte waargeneem word by die reënboog forel nie. ‘n Moontlike rede hiervoor kon wees dat die konsentrasie van P. marcusii wat by die kos gevoeg is te laag was. Dit is egter ook moontlik dat die astazantien vernietig was voordat dit deur die forel opgeneem is aangesien astazantien ‘n baie onstabiele molekuul is. Verder het ons die impak van verskillende visvoer behandelings op die mikrobiese gemeenskappe in die spysverteringskanaal (SVK) van forel tydens die verloop van die proef bestudeer. Geen ooreenkomste in mikrobiese gemeenskap strukture in die forel SVK is waargeneem tussen die verskillende voer behandelings nie, maar daar is wel ooreenkomste gevind tussen die mikrobiese gemeenskappe van visse by spesifieke tyd intervalle (Hoofstuk 4).
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Hudelson, Karista. "Ultraviolet Radiation Tolerance in High Elevation Copepods from the Rocky Mountains of Colorado, USA." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc103331/.
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Copepods in high elevation lakes and ponds in Colorado are exposed to significant levels of ultraviolet radiation (UV), necessitating development of UV avoidance behavior and photoprotective physiological adaptations. The copepods are brightly pigmented due to accumulation of astaxanthin, a carotenoid which has photoprotective and antioxidant properties. Astaxanthin interacts with a crustacyanin-like protein, shifting its absorbance from 473 nm (hydrophobic free form, appears red) to 632 nm (protein-bound complex, appears blue). In six sites in Colorado, habitat-specific coloration patterns related to carotenoprotein complex have been observed. The objective of this study was to determine whether pigment accumulation or carotenoprotein expression has a greater effect on resistance to UV exposure. For each site, copepod tolerance to UV was assessed by survivorship during UV exposure trials. Average UV exposure was determined for each habitat. Astaxanthin profiles were generated for copepods in each site. Ability to withstand UV exposure during exposure trials was significantly different between color morphs (p < 0.0001). Red copepods were found to tolerate 2-fold greater levels of UVB than blue or mixed copepods. Additionally, red copepods have much higher levels of total astaxanthin than blue or mixed copepods (p < 0.0001) and receive a higher daily UV dose (p < 0.0003). Diaptomid carotenoprotein sequence is not homologous with that of other crustaceans in which crustacyanin has been characterized which prevented quantification of carotenoprotein transcript expression. Overall, diaptomid color morph may be an important indicator of UV conditions in high elevation lentic ecosystems.
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Byrtusová, Dana. "Optimalizace podmínek kultivace řasových kultur ve fotobioreaktorech." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240535.
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Presented diploma thesis is focused on the optimisation of Haematococcus pluvialis cultivations in different photobioreactors and on biotechnological production of astaxanthin. Theoretical part summarized the knowledge about optimal growth and production conditions of secondary metabolites. Followed research was focused on actual cultivation systems and on the possibilities of metabolite and nutrient monitoring. In experimental part the growth characteristic of the strain from Březova nad Svitavou (HMP-CCALA 375) was analyzed under optimal cultivation conditions on white and red light. During culture growth the profile and the concentration of carotenoid pigments were determined. The best yield of biomass was achieved in the cultivation on white light (0,939 g/l),carotenoids lutein and -carotene were observed as dominant pigments. In the next experiments optimal growth medium, temperature and light intensity were determined for cultivations of four chosen HMP strains from Germany, America, Africa and Switzerland. The most suitable cultivation medium was found BBM, oppositely the worst results were obtained with BG11. In previous experiments cultivation temperature 22 °C was determined as optimal value for comparative strain HMP – CCALA 375. Selected four strains were cultivated at 22 °C, as well as at 25 °C. Higher temperature was more optimal mainly for Switzerland, German and Africa strains. By analyzing of light intensity influence, it was found that the best increase of biomass was induced by the adaptation of culture on lower illumination (50 µmol photones•m^-2•s^-1) followed by higher light intensity (100 - 150 µmol photones•m^-2•s^-1). HMP from Switzerland showed the best growth results during all cultivation experiments, so this strain could be perhaps useful for industrial production of astaxanthin. In the last part of work, the influence of stress conditions on astaxanthin production by strain from Březova nad Svitavou (HMP – CCALA 375) was studied. Followed stress factors were used: high intensity of light (1 000 µmol photones•m^-2•s^-1), low nitrogen concentration (32,96 mg/l), addition of sodium chloride (0,5%), influence of sodium acetate (2,2 mM) and combination of sodium chloride and sodium acetate (0,5% NaCl, 2mM NaAc). Due to strong illumination (1 000 µmol photones•m^-2•s^-1) the best yield of astaxanthin was obtained (more than 20 mg/g). According to literature [103, 105] significant amount was also observed by addition of sodium acetate (9,2 mg/g). Oppositely minimal astaxanthin production was showed in presence of salt stress (3,8 mg/g). In followed experiments should be studied the influence of stress combinations on HMP – CCALA 375 strain as well as on other suitable strains of H. pluvialis with the aim to achieve the maximal yield of astaxanthin significant for large scale cultivation.
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CHEN, PEI-CHI, and 陳沛綺. "Effect of astaxanthin and astaxanthin formula on thrombotic risk factors in type 2 DM patients." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/76752040983298629065.
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碩士靜宜大學
食品營養學系
102
Macrovascular complications are the major causes of death among diabetic patients, and hyperglycemia-induced oxidation and subsequent chronic inflammation play an important role in the etiology of diabetic macroangiopathy. Astaxanthin (AX) is one of the carotenoids with excellent anti-inflammatory and antioxidative capacity; therefore, the purpose of this study was to investigate the effect of astaxanthin and astaxanthin formula (AXF) on thrombogenic risk in type 2 diabetic patients. One hundred and three type 2 diabetic patients were recruited from Cheng Ching Hospital in Taichung city. After exclusion of unqualified patients, all subjects were randomly assigned into three treatment groups including placebo group (P), AXF (AX 6 mg + vitamin E 150 mg + Tocotrienol 45 mg/day) group and AX (AX: 14 mg/day) group, respectively. After two month’s supplementation, plasma concentration of AX, fasting blood glucose (FBG), HbA1c, lipid profiles, markers of hepatic and renal function, oxidative and inflammatory markers, coagulation and anti-coagulation factors were measured. The results showed that plasma levels of AX increased by supplementation in a dose-dependent manner. Plasma concentration of HbA1c, CRP and vWF was significantly decreased in AXF group. Plasma concentration of HbA1c, TG and TC, GPT, inflammatory cytokines of TNF-α, CRP and vWF was significantly decreased in AX group. In addition, plasma concentration of coagulation factor VII and PAI-1 was significantly decreased, and AT-III level was significantly increased in AX group. In conclusion, AX supplementation for two months may have beneficial effects on type 2 DM patients in ameliorating hyperglycemia, hyperlipidemia and liver malfunction. AX supplementation also decreases oxidation stress and inhibits chronic inflammation, hence ameliorates endothelial damage and thrombogenic risk in type 2 DM patients.
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Lee, Shu-Chih, and 李書志. "Feasibility of simultaneous production of astaxanthin and transfructosylating enzyme from an astaxanthin-hyperproducing mutant Xanthophyllomyces dendrorhous." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/01086786859005167476.
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博士國立中興大學
食品暨應用生物科技學系所
99
In this study, the wild strains of X. dendrorhous CBS 6938 and P. rhodozyma BCRC 21346 were treated with mutagenic agent N-methyl-N''-nitro-N-nitroso-guanidine (NTG) and plated on yeast malt (YM) agar containing b-ionone as a selective medium. One of mutant isolate (X. dendrorhous NCHU-FS701) was found to contain more than threefold of astaxanthin content compared with the parental strain X. dendrorhous CBS 6938. The total carotenoids content of the mutant NCHU-FS701 was 1,508 ug g-1 yeast, and 87% of the total carotenoids was astaxanthin. The mutant NCHU-FS701 could produce higher astaxanthin concentration, but it grew slower than parental strain CBS 6938 in YM broth. The cost-down medium including molasses, urea, and CaCl2 were selected and optimized by using Box-Behnken design under shaker flask cultivation of X. dendrorhous NCHU-FS701. Maximum astaxanthin production of 11 g ml-1 was obtained with the medium composition of 43.4 g L-1sugar as glucose equivalent in molasses, 2.49 g L-1 urea, and 0.73 g L-1 CaCl2. Based on the media composition, cell growth and astaxanthin production were enhanced when scale up of astaxanthin production was conducted in a 5-L stirred tank reactor with continuous air supply and pH control. Cell disruption was needed because the astaxanthin and transfructosylating enzyme are intracellular. The optimal setting for 30 g-DCW L-1 yeast cell disruption was found to consist of 0.5-mm-diameter glass bead at 10°C by using a bead beater for 20 min, in which more than 97% yeast disruption could be observed under microscopy. The disrupted cell culture was then extracted with hexane/ethyl acetate, and 72% total carotenoids in the organic solvent phase and 446 U mg-1 protein of transfructosylating enzyme activity in the water phase was obtained, indicating a simple step for simultaneously obtaining astaxanthin and transfructosylating enzyme. For the production of fructooligosaccharides (FOS), the transfructosylating enzyme was immobilized onto chitosan using Tris (hydroxymethyl) phosphine (THP) as coupling agents. The optimal pH was 5.0 and the optimal temperature was 60oC for both free and immobilized enzyme. The THP-immobilized enzyme had better thermal stability, with 70% residual activity even after 10 repeated runs at 60oC. Metal ions, such as K+ and Fe3+ had positive effect on the enzyme activity.
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Chang, Wan-Ling, and 張菀玲. "Preparation and characterization of astaxanthin nanoparticles." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/29133314798129278246.
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Shen, Yu-Tsung, and 沈侑宗. "Production of Astaxanthin with Phaffia rhodozyma." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/26245421640400037122.
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碩士明志科技大學
生化工程研究所
101
Astaxanthin is a type of unsaturated compound terpenoids which is highly valuable among over 600 types of carotenes. There have been multiple researches that report on the functions of Astaxanthin in enhancing immune system and inhibit tumor cells. The liquid culture of Astaxanthin produced from yeasts is the primary culture method used in research conducted by major companies for that a massive amount of yeast-based Astaxanthin produced within a short time and limited space has a high potential in the commercial and economic development. The fermentation results of the study show that the amount of Astaxanthin produced from Xanthophyllomyces dendrorhous yeast was more than the amount produced from Phaffia rhodozyma yeast. Next, by using a fermentor as pH control, the amount of Astaxanthin produced with pH control was comparatively higher than the amount of Astaxanthin produced without pH controlled. The output of Astaxanthin produced from Phaffia rhodozyma yeast under 60 hours of fermentor culture was 1.87 mg/g DCW, while the output of Astaxanthin produced from Xanthophyllomyces dendrorhous yeast was 2.34 mg/g DCW. The outputs for Astaxanthin produced from Xanthophyllomyces dendrorhous yeast with pH value controlled and without were 0.4713 g-biomass/ g-glucose and 0.4127 g-biomass/ g-glucose, respectively. Later, we used four different extraction methods to extract the Astaxanthin produced from two strains of different yeasts, whereas the outputs of Astaxanthin produced from Phaffia rhodozyma yeast through the methods were 32μg/ml, 49μg/ml, 0μg/ml, and 0μg/ml, respectively. The outputs of Astaxanthin produced from Xanthophyllomyces dendrorhous yeast through the methods were 43μg/ml, 56μg/ml, 0μg/ml, and 0μg/ml respectively. The maximum output of Astaxanthin was attained from Xanthophyllomyces dendrorhous yeast by using Method B. The Astaxanthin produced from yeasts were recombined, trapped and analyzed with Actin genes, followed by development culture on the three different mediums, YM, MM and MB, in addition to comparing the content of Astaxanthin. It was discovered that MM was the best medium and was used as the optimal carbon source concentration for MM medium. The optimal carbon source concentration for the Astaxanthin of yeasts in MM medium was 50g/L, yielding a content of 640 g/ml Astaxanthin. Finally, the Astaxanthin underwent HPLC identification and it was discovered that algae-based Astaxanthin only showed S wave while yeast-based Astaxanthin only showed R wave. The MASS of algae on the spectrum analyzer was 595.4 m/z while the MASS of yeast was 593 m/z. During the test for anti-oxidation, the anti-oxidation of Astaxanthin using DPPH was 4ppm while the anti-oxidation of Beta carotenes was only 3ppm, indicating significantly stronger anti-oxidation of Astaxanthin. Keywords: Astaxanthin, Algae, Yeast
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Kuo, Yi-Ting, and 郭一廷. "Optimize the cultural condition for astaxanthin production in Chlorella. sp. DT and produce astaxanthin by transgenic plant." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/31614131525910816499.
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碩士國立中興大學
基因體暨生物資訊學研究所
103
The Chlorella sp. DT, an endemic species in Taiwan, was found with astaxanthin producing ability. To maximize productivity of astaxanthin in Chlorella sp. DT, NaNO3, Na2CO3 and CaCl2 were selected as inducers by factors screening. Further, response surface methodology was used to optimize the cultural condition for astaxanthin production. The results showed astaxanthin productivity was 0.749 mg L-1 after 10 days of cultivation and induction by used the optimized the cultural condition, BG11 medium with NaNO3 2779.08 mg L-1, Na2CO3 273.97 mg L-1 and CaCl2 75.34 mg L-1. Furthermore, based on factors screening, the culture conditions for two-stage to produce astaxanthin by Chlorella sp. DT were developed. The PBD-2 medium was used to accumulate biomass in green-stage, and the Pred-medium was used for astaxanthin production in induce-stage. Astaxanthin productivity is 0.805 mg L-1 after 12 days of cultivation and induction in two-stage strategy. We successfully maximize the astaxanthin production in Chlorella sp. DT by one and two-stage of cultivation strategies. To increase the production of astaxanthin, we cloned the Chlorella sp. DT β-carotene ketolase (BKT), the key enzyme of astaxanthin synthesis, and overexpressed the BKT gene in Nicotiana tabacum and N. benthamiana by using agrobacterium-mediated transformation. The transgenic N. tabacum and N. benthamiana plants can produce 604.6 and 385.8 μg astaxanthin per g (dry weightof leaves), respectively. This study successfully used β-carotene ketolase gene form Chlorella sp. DT to build a transgenic plant system for astaxanthin production.
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Huang, Chih-Chung, and 黃志忠. "Combined Effects of Dietary Astaxanthin and Vitamin A on Body Astaxanthin and Vitamin A Composition of Penaeus monodon." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/88730005238994647145.
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碩士國立海洋大學
水產養殖學系
90
Astaxanthin (AS) has been found for tiger prawn Penaeus monodon to increase its resistance to stress and concomitantly the survival. It has been also demonstrated vitamin A (VA) a requirement for P. monodon. AS and VA may involve each other in the roles to play in nutrition. This study therefore aimed to evaluate the effects of combinations of AS and VA in diet on growth and survival of P. monodon and AS, VA, and activities of antioxidase in its body. Seven experimental diets were used. Serving as a blank, Diet B contained no AS and VA. Diets for six treatments their concentration for AS and VA together was 100 mg/kg diet. D0 contained 0 mg AS but 100 mg (or 275000IU equivalent) VA/kg. D100 had 100 mg AS/kg but no VA. D20, D40, D60, and D80 had AS 20 mg, 40 mg, 60 mg, and 80 mg and also VA 80 mg, 60 mg, 40 mg, and 20 mg/kg, respectively. Each diet trial had 4 replicates. After 12-week rearing, D20 prawn had best survival and growth. Body astaxanthin was dominated by esterified astaxanthin, of which diester astaxanthin (DA) was more abundant than monoester astaxanthin (MA). Free astaxanthin (FA) was in insignificant amount. Body FA decreased with rearing duration and increasing astaxanthin fraction (AF) in diet. MA decreased with decreasing AF. Total astaxanthin (TA) increased linearly with AF and rearing duration accelerated the increasing trend. Complicate interactions made the change in body VA unparallel along AF and rearing duration, appearing as a right-skewed saddle. Diet VA was transformed to part of body FA, but not to MA or DA. Diet FA could be transformed completely to body VA. When diet AF increased, in a steady fashion, the activity of total antioxidant status (TAS) and glutathione reductase increased and superoxide dismutase (SOD), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) decreased. TA, MA, and DA had significant correlations with all 5 enzymatic activities. Body FA was correlated with AST and ALT. Body VA was not correlated with any of the 5 enzymatic activities. Diet AS but not VA enhanced antioxidant capability and improved hepatopancreas function in P. monodon.
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Hix, Lauram. "Cancer Chemoprevention By Water Soluble Astaxanthin Derivatives." Thesis, 2004. http://hdl.handle.net/10125/10399.
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Ke, Yi-Ju, and 柯怡如. "Preparation of astaxanthin microemulsion and cosmetic cream." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/32132849420474883107.
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CHENG, YI-SHIN, and 鄭怡心. "Production of astaxanthin by yeast Phaffia rhodozyma." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/53237052272600729608.
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WANG, JUI-LUNG, and 王瑞龍. "Pomacea Canaliculata Eggs Astaxanthin Extraction Process Development." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/18913898759760224067.
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碩士明志科技大學
化學工程系生化工程碩士班
105
Abstract Astaxanthin has been verified as food with effective anti-oxidation and health function. This article will be presenting how to search for the economical way of extracting the highest Astaxanthin from various sources and simplification of the production. Pomacea canaliculata will be the main source, the use of carotenoid-protein by adding ethanol to separate protein and Astaxanthin, investigating the concentration of ethanol, duration of mixing, then using suction filtration to separate solid protein and Astaxanthin ethanoate solution. Successful experiment result could depend on the production strategy of extracting Astaxanthin from Pomacea canaliculata. The process is simpler for dulse, yeast, waste products and seafood. This method of extracting Astaxanthin is more profitable and its concentration is also prominent. The following-up animal testing also showed that the extracted Astaxanthin from this method could be fully applied to feeds, food and skin products. Keywords: Astaxanthin、Pomacea canaliculata、Extracted
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Lin, Ya-Ting, and 林亞葶. "Effects of Pomacea canaliculata Astaxanthin Protein and Astaxanthin Egg on Plasma and Liver Lipid and Antioxidant Activities inHypercholesterolemia Hamster." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/7rupr5.
Full textAbstract:
碩士實踐大學
食品營養與保健生技學系碩士班
101
To understand the health function of astaxanthin from Pomacea canaliculata extract, the extract was combined with protein which named astaxanthin protein powder (APP). Then fed chickens of astaxanthin can obtain astaxanthin egg yolk powder (AEYP). In this study, analysis content composition powder and function for AP and AE according to AOAC methods. The composition content, cholesterol and astaxanthin concentration, are analysis about astaxantin protein powder (APP). The cholesterol and astaxnathin concentration, fatty acid composition are analysis about astaxnathin egg yolk powder (AEYP). In animal study, the sixty-four hamster are purchased from National Animal Experimental Center, then divided into eight groups, B (Basic Diet), BC (Basic Diet with 0.2 % cholesterol), low, medium, high dose astaxanthin protein powder (4, 8, 20 mg APP/Kg BW/day) and low, medium, high dose astaxanthin egg yolk powder (1, 1.5, 2 AEYP/Hamster/day). All animals are sacrifice after six weeks and analyse lipid profile and antioxidant enzyme activity. The results show that APP contain 17.00±0.12% water, 39.00±0.98% crude protein, 12.00±1.21% crude fat, 0.86±0.01% crude fiber, 10.00±0.09% ash, soluble non-nitrogen compound 21.14±0.71%, cholesterol 0.86% and astaxanthin 1.00%. The composition of AEYP, astaxanthin is 1.25 mg% of egg yolk weight. Liver triglyceride to each group are 36.42±3.57 mg/g liver, 37.26±5.73 mg/g liver and 33.75±2.88 mg/g liver of 4APP, 8APP and 20 APP, were significantly lower than that of BC group 47.49±5.25 mg/g liver. Plasma MDA concentration of 4APP and 8APP groups that was significantly lower than BC group about 27% and 24.9%, respectively. In liver, it shows liver vitamin C concentration of 8APP group that were significantly higher than BC group abuot 12.9%. Liver catalase activity of 1.5AEYP and 2AEYP groups that were significantly higher than BC group 34% and 46.4%, respectively. Liver vitamin E contration in 20 APP group is significantly higher than BC group. Liver reducing power of 4APP、8APP、20APP that were significantly higher than BC group about 40.5%、39.11%、44.05%, respectively. From the results, astaxnathin protein powder (APP) astaxanthin egg yolk powder (AEYP) can improve concentration of plasma lipid peroxide marker malondialdehyde (MDA) and enhance liver antioxidant enzyme activity. keywords：Pomacea canaliculata, astaxanthin, malondialdehyde, catalase, reducing power
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CHUAN, CHUANG KAI, and 莊凱荃. "The Studies of Haematococcus pluvialis Cultivation for Astaxanthin Production." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/t7uk8n.
Full textAbstract:
碩士逢甲大學
化學工程學系
102
Haematococcus pluvialis contain with abundant natural astaxanthin, which is full of antioxidant capacity that can quench free radicals, improve immune system, and prevent aging and cancer. Up to now, natural astaxanthin has been discovered as a most powerful antioxidant in natural resources. In this study, it’s divided into two steps to cultivate Haematococcus pluvialis. Before the first step, we found that replacing fresh medium regularly can nurture Haematococcus pluvialis effectively. In the first step of culture, use Taiguchi method to search for the optimal experimental condition for Haematococcus pluvialis production. The result shows that the optimum growth rate is 0.262 d-1, with the medium (JM) in N:C:P=1:2:5, irradiation of red light LED at illumination of 1600 lux, culturing for 10 days. In the second step of culture, it shows that the color in Haematococcus pluvialis will be accelerated from green to red, and get the concentration of Astaxanthin about 3.2 mg L-1, with the medium (JM), which is without main Nitrogen, irradiation of blue light LED at illumination of 8000 lux. Using vertical tubular photobioreactor to cultive Haematococcus pluvialis for 7 days in un-circulated condition, the concentration of algae reached 50×104 cell mL-1. As a result, the growth rate of algae was 0.291 d-1.