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1
Barnby, F. M. "An investigation of the pectinolytic enzyme system of Kluyveromyces marxianus". Thesis, University of Reading, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378305.
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Larsson, Malin y Annie Nilsson. "Förädling av stjälkfibrer för fler naturliga fiberalternativ : Enzymbehandling för avlägsnande av pektin i stjälkfibrer för ökad spinnbarhet". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-295.
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Grewia optiva är en utav många outnyttjade stjälkfibrer som skulle kunna bidra till ökandet utav de naturliga fiberalternativen. Fibern har idag inte så många användningsområden på grund utav dess hårda och styva uppbyggnad, vilket gör den svår att spinna till garn. På uppdrag av organisationen Bhartiya Gramotthan Sanstha (BGS) har i detta projekt en redan befintlig metod utvecklats för att förädla fibern. Vad som främst eftersöktes var nedbrytandet av pektin som är en av de faktorer som bidrar till fiberns hårda och styva struktur. I metoden användes biologiskt nedbrytbara enzym som katalysatorer. En fungerande metod skulle kunna öka användningsområdet hos stjälkfibrer generellt och öka möjligheten till användandet utav fler naturliga fibrer. Enzymet som har använts i metoden är ett pektatlyas EC 4.2.2.2 som katalyserar reaktionen som sker då pektinmolekyler klyvs. För att effektivisera processen adderades en komplexbildare, EDTA, som tidigare visat goda resultat för lin. Efter enzymbehandlingen skedde en viktreduktion av fibrerna samt förändring av deras utseende. I svepelektronmikroskop observerades förändring av ytstruktur samt separation mellan fiberbuntarna. Dessa parametrar är viktiga och har stor inverkan på spinnbarheten hos fibrer. I projektet har försök att spinna fibern gjorts men inte lyckats helt. Förändringen på ytstruktur och separation mellan fibrerna tyder dock på att behandlingen är ett steg i rätt riktning.Grewia optiva is one of many unused bast fibres that could contribute to an increase of natural textile fibres on the industrial market. This fibre has to-day not as many applications due to its stiff and hard structure that makes the fibre difficult to spin into yarn. On behalf of the organisation Bhartiya Gramotthan Sanstha (BGS) has an existing method been developed to process the Grewia optiva fibre. The method is developed to break down substances like pectin that is responsi-ble for the hard and stiff structure of the fibre. Degradable biological en-zymes were used as catalyser in the method. With a functioning method like this the applications of bast fibres could increase and contribute to the use of more natural fibres. The enzyme used to catalyse the chemical reaction and the cleavage of pec-tin molecules in this method was a pectate lyase EC 4.2.2.2. In this method EDTA was used as a chelator to efficient the chemical process. EDTA has been used as a chelator in earlier reports and showed good results. After the enzymatic treatment a weight reduction of the fibre was notable. In SEM-analysis separation between fibres and changes on the fibre surfaces was observed. These parameters are important and affect the spinning capability of the fibre. To test the spinning capability of the enzyme treated fibre they were spun in a ring spinning system, unfortunately not successfully. The surface changes and the separation shows that the enzymatic treatment had occurred and indicates that the method has developed in the right direction.
3
Takeya, Tomoyuki. "Synthetic biological studies on production of methanol from natural resource-derived carbon compounds". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263712.
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Ali, Ahmed. "Use of pectinases to improve the nutritive value of lupins for poultry". University of Western Australia. School of Animal Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0094.
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[Truncated abstract] Australia produces 87% of the worlds lupins (Lupinus angustifolius) which have the potential to be an excellent source of protein and energy in animal diets. However, feed manufacturers and poultry producers cannot use more than about 5% lupins in broiler and 7% in layer diets. The main reason is because 34% of the lupin grain comprises complex cell-wall polysaccharides that are indigestible. The main component of cell walls in lupins is pectin (33%). Poultry cannot digest pectin because they don't secrete the appropriate enzymes so their ability to use lupins is limited. Undigested pectins increase the viscosity of digesta in the bird's digestive tract, which in turn reduces the digestibility of dry matter and efficiency of feed utilisation. Pectins also increase water-holding capacity, a characteristic directly related to water intake and wet droppings. In this thesis, I tested the general hypothesis that breakdown of cell walls and pectins will improve the nutritive value of lupins for broilers and layers and reduce wet droppings. This hypothesis was tested in six experiments by treating lupins with specific exogenous enzymes (pectinases) or mechanical-heat treatment (expansion) plus pectinase. In the first experiment, attempts to break down the cell walls and pectins using four doses of pectinase, specifically polygalacturonase (PG), succeeded in improving the nutritive value of whole and dehulled lupins for egg layers. The lowest dose, 0.6g/kg diet, was the most effective dose for reducing water intake, wet droppings, the viscosity of the digesta and the number of soiled eggs. ... Equivalent figures for layers were 14, 15, 5 and 8%, indicating that the pectinases were slightly more effective in layers than broilers. For diets containing 20% dehulled lupins, pectinases were also very effective at breaking down both pectin and cell walls to release nutrients and, concomitantly, reducing water intake and wet droppings, but the magnitude of the responses was slightly less than with the 10% dehulled lupin diets. For diets containing 30% dehulled lupins, although the pectinases again were effective at breaking down pectin and cell walls and reducing viscosity, they did not reduce water intake or wet droppings. This might be due to the large amounts of nonmethylated pectic polysaccharides, which make up two thirds of the cell walls, by increasing water-holding capacity particularly when dehulled lupins are included in the diet at high levels (up to 30%). These polysaccharides might be broken down by appropriate enzymes. This hypothesis is worth testing in the future. Overall, the results of my study supported the general hypothesis. These in vivo results are conclusive and consistent. They show that an optimum combination of PME and PG is capable of including dehulled lupins up to 20% in broiler and layer diets without any nutritional or hygienic problems. The strategies I developed have proven very useful for breaking down the cell walls and pectins, improving the nutritive value of lupins for broilers and layers, and reducing wet droppings. By using the optimum combination of two pectinases, it should be possible to make substantial improvements in the nutritive value of lupins for broilers and layers, most importantly by reducing excessive water intake and wet droppings associated with feeding dehulled lupins. Without pectinases, the amount of dehulled lupins used in poultry diets is fairly small (7%), but if pectinases are used, this upper limit can be lifted to 20%.
5
Massiot, Patrice. "Caracterisation structurale et degradation enzymatique des polysaccharides de parois cellulaires de la racine de carotte (daucaus carota l. )". Rennes 1, 1988. http://www.theses.fr/1988REN10089.
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McKie, Vincent Arthur. "The isolation and characterisation of pectin degrading enzymes". Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287822.
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Legentil, Anne. "Étude de la composition chimique des pectines de la paroi cellulaire de la fraise et de leur solubilisation par des préparations enzymatiques industrielles : application à la liquéfaction de la fraise". Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL018N.
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Le procédé de liquéfaction des fruits, nécessite l'emploi d'enzymes pectinolytiques, considérées comme des auxiliaires technologiques. L’optimisation de l'hydrolyse enzymatique passe par une meilleure connaissance de la paroi cellulaire du fruit. La paroi cellulaire de la fraise a été isolée du fruit par une extraction à l'alcool. Le matériel ainsi obtenu (MIA) a été soumis à des extractions successives par l'acide trans-1,2-diamino-cyclohexane-n,n,n',n'-tétraacétique, un tampon succinate pH 4,8, l'acide chlorhydrique dilué à chaud et la soude diluée à froid. L’analyse des différents extraits a permis de montrer que 87% des pectines solubles de la fraise sont extractibles par un agent chélatant du calcium (CDTA). Ces pectines sont faiblement méthylées et peu ramifiées. Les pectines les plus ramifiées nécessitent des conditions d'extraction plus drastiques (HCl et NaOH dilués). Le fractionnement par chromatographie échangeuse d'ions a permis de montrer que certaines fractions pectiques sont riches en oses neutres pouvant provenir des hémicelluloses (xylose, glucose), et en protéines. Les résultats obtenus permettent de suspecter la présence de liaisons entre les pectines, les hémicelluloses et les protéines au sein de la paroi cellulaire. La liquéfaction de la paroi (MIA) et de l'extrait insoluble dans le CDTA à l'aide d'enzymes industrielles a mis en évidence, outre la synergie entre les activités pectinolytiques et cellulolytiques, l'importance des activités hémicellulolytiques et protéolytiques. Ces études ont permis de mettre au point une nouvelle formulation enzymatique permettant d'améliorer le rendement d'extraction du jus et d'optimiser la stabilité des anthocyanes (couleur) au cours du stockage. En outre, cette étude a montré l'effet néfaste de la pasteurisation et de la concentration sur la couleur des jus
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Şimşek, Şebnem Yemenicioğlu Ahmet. "Production of commercially suitable pectin methylesterase and polyphenol oxidase from agro-industrial wastes/". [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/gidamuh/T000508.doc.
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Faraj, K. A. "A study of pectic substances and their enzymic degradation". Thesis, University of Strathclyde, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372091.
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Miyawaki, Miyuki. "Control of polyphenol oxidase and pectin methylesterase activities by ultra high pressure". Online access for everyone, 2006. http://www.dissertations.wsu.edu/Dissertations/Spring2006/M%5FMiyawaki%5F033106.pdf.
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Li, Dan 1971. "Immobilization, characterization and use of fish protease". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102996.
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Enzyme immobilization as a technique attaches free forms of enzyme molecules to stationary support materials to permit enzymes to be reused several times. Bovine trypsin as a model enzyme was immobilized onto controlled pore glass (CPG) beads to investigate the optimum conditions for immobilization, as well as the physico-chemical properties of the immobilized enzyme versus the free form of the enzyme. At pH 9, about 60% of the enzyme protein incubated with CPG was immobilized onto the CPG, and immobilized bovine trypsin activity was determined as 0.265 BAPNA U/g CPG beads. The immobilized bovine trypsin showed lower affinity for its substrate, lower susceptibility to inhibition by soybean trypsin inhibitor and higher thermal stability, while the optimum pH and optimum temperature values were shifted to higher values compared to those of the free enzyme. The immobilized enzyme was evaluated for its capacity to extract carotenoproteins from shrimp shell. After 11 re-uses, the immobilized enzyme retained about 77% of its initial activity, and the total yield of the product from the same immobilized trypsin was 4.3 times higher than a single use of the same amount of the free enzyme. Cunner fish is a cold water adapted, stomachless teleost fish. Cunner fish trypsin possesses some unique properties compared with homologous trypsins from (i) species acclimated to warm temperature regimes, and (ii) species with functionally distinct-stomachs. Cunner fish trypsin was extracted from pancreatic tissue, and immobilized onto CPG beads using glutaraldehyde as cross-linking reagent. The influence of enzyme loading, the properties of the immobilized enzyme in terms of specific activities, and responses to pH and temperature were investigated. The kinetic properties and operational stability of the immobilized cunner trypsin were studied as well. The pH optimum of the immobilized fish trypsin shifted from pH 8.5 to pH 9, and the temperature optimum also increased from 45ºC to 50ºC versus the free form of the cunner enzyme. The catalytic efficiencies (Vmax/Km) of the immobilized fish trypsin were determined for both amidase and esterase reactions, using BAPNA and TAME as substrates and were found to be greater than those of immobilized bovine trypsin. Thus, the immobilized cunner fish trypsin had a higher catalytic capacity for the hydrolysis of both the amide and ester substrates. The operational stability of immobilized fish trypsin was studied by extracting carotenoprotein from shrimp shell. The immobilized fish trypsin retained 75% of its initial hydrolytic capacity after 11 re-uses, and the yield obtained was over 20% higher than that of immobilized bovine trypsin. When the immobilized cunner fish trypsin was applied to digest native pectin methylesterase (PME), it exhibited greater capacity to inactivate the PME than immobilized bovine trypsin. The inactivation efficiency of the immobilized fish trypsin was 20% higher than that of the immobilized bovine trypsin. The inactivation of PME was influenced by PME concentration, incubation time and temperature. In general, higher temperature, longer incubation period, and lower initial PME concentration produced more PME inactivation. PME inactivated by immobilized fish trypsin and bovine trypsin regained part of its activity during storage at 4ºC. The initial PME concentration affected the reactivation period. The kinetic studies indicated that the inactivation rate constants increased and D-values (time to inactivate 90% of the enzyme) decreased with increasing temperature for both immobilized fish trypsin and bovine trypsin. The activation energy (Ea) of PME inactivation by the immobilized fish trypsin was lower than that by the immobilized bovine trypsin, which explains why the immobilized fish trypsin had higher catalytic capacity at various temperatures than immobilized bovine trypsin.
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Gaffé, Joël. "Contribution à l'étude des pectine-méthyl-estérases des parois végétales du lin". Rouen, 1992. http://www.theses.fr/1992ROUES039.
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Une activité pectine-méthyl-estérase ioniquement liée à la paroi végétale du lin a été extraite de cals et de jeunes plantes de lin. Cette activité enzymatique libère une fonction carboxylique à partir d'un méthyl ester de galacturonate. 6 isoformes de pI variant de 5,5 à plus de 9 sont observées. Une forme, de point isoélectrique supérieur à 9, a été partiellement purifiée, ses caractéristiques, masse moléculaire, proche de 67000, une affinité de 0,27% pour une forme et de 0,072% pour l'autre isoenzyme. Les formes neutres présenteraient un mode d'action différent de celui de la forme basique. La répartition de ces isoenzymes dans la plante est hétérogène. Toutes les isoenzymes sont observées dans les cotylédons et dans l'apex de l'hypocotyle. Dans la racine et la base de l'hypocotyle, seul l'isoforme basique est révélée après focalisation isoélectrique. Compte tenu de leurs différentes caractéristiques, un rôle possible est proposé pour ces différentes formes
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TRINDADE, L. C. "Simulação computacional do efeito da pressão sobre a enzima pectina metilesterase do tomate". Universidade Federal do Espírito Santo, 2018. http://repositorio.ufes.br/handle/10/7374.
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Previous issue date: 2018-02-23Este trabalho descreve o desenvolvimento de uma simulação computacional, desenvolvida através do programa GROMACS. Mais especificamente, estudamos os resultados da simulação computacional referente a evolução do raio de giro da proteína Pectina Metilesterase (PME) do tomate em função da pressão aplicada, mantendo a temperatura fixa. Foi realizada uma descrição sobre os modelos físicos utilizados pelo programa. Também foi descrito, de forma suscinta, características sobre sistemas e estruturas dos aminoácidos e proteínas. As simulações computacionais consideraram uma temperatura de 26, 85oC e pressões aplicadas de 1 bar, 1 kbar, 3 kbar, 5 kbar, 7 kbar, 9 kbar e 10 kbar. As simulações trabalharam com um tempo de ação da pressão de até 100 pico segundos. Os resultados da simulação computacional indicaram uma redução não linear do raio de giro da enzima Pectina Metilesterase (PME) do tomate de acordo com o aumento da pressão aplicada, mantendo temperatura fixa.
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Paixão, Airles Regina da Costa. "Ação da pectina metil esterase e cloreto de cálcio no armazenamento e controle da podridão-mole em pimentão". Universidade Federal de Sergipe, 2016. https://ri.ufs.br/handle/riufs/3011.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESThe pepper (Capsicum annuum L.) has commercial importance, by having sources of vitamins, minerals and fiber. However, a post-harvest problem, excessive softening which reduces the life and favors action pathogens such as Pectobacterium caratovorum subsp. caratovorum- Pcc, causal agent of soft rot, a major disease of post-harvest chili that is favored by the reduction of firmness. One technique that has recently been used for firmly maintaining the application is pectin methyl esterase (PME) with the addition of a calcium solution prologando thus reducing its lifetime and pathogen attack. The objective of this study was to use methyl pectin esterase (PME) exogenous associated with calcium chloride in maintaining firmness and control of Pectobacterium caratovorum subsp. caratovorum about pepper. The first experiment was conducted in a completely randomized design in a 4x5 factorial scheme with three replications for 12 days, evaluated every three days. In the second experiment, the test was conducted in a completely randomized design in a factorial 5x5 with three replications. In the first study the fruits of pepper were subjected to vacuum infusion method with pressure of 200 mmHg for 5 minutes, and following evaluated the loss of weight (PMF), fruit firmness (FF), skin color ( CC), soluble solids (SS), pH, total acidity (TA) and activity of SMEs. In the second test the fruits of pepper were subjected to vacuum infusion method with pressure of 200 mmHg for five minutes, then the fruits were inoculated with the PCC then held the fruit firmness analysis (FF), SME activity and the severity of the disease in chili (SD). The fruits obtained in general a reduction of over time firmly in all treatments but was found significant effect in maintaining the fruit firmness when treated in vacuum infusion with calcium chloride, without altering the physicochemical characteristics, as soluble solids content, total acidity and activity of SMEs, slowing the fruit ripening process. The fruits when treated with vacuum infusion with calcium chloride associated with pectin methyl esterase was not favorable because it altered the physicochemical properties chili, highlighting the decline of firmness, thus deteriorating the quality of the fruit. Regarding inoculation Pcc in the fruit was observed inhibition of growth of this pathogen, prolongation of fruit and better firmness treated fruits infusion over calcium inoculation Pcc chloride.
O pimentão (Capsicum annuum L.) tem grande importância comercial, por possuir fontes de vitaminas, minerais e fibras. Contudo, possui problema pós-colheita, o amolecimento excessivo que reduz a vida útil e favorece ação de patógenos como a Pectobacterium caratovorum subsp. caratovorum- Pcc, agente causal da podridão-mole, uma das principais doenças da pós-colheita do pimentão que é favorecida pela redução da firmeza. Uma técnica que vem sendo utilizada recentemente para a manutenção da firmeza é aplicação da pectina metil esterase (PME) com a adição de solução de cálcio prologando, assim, a sua vida útil e diminuindo o ataque do patógeno. Assim, o objetivo do trabalho foi utilizar a pectina metil esterase (PME) exógena associada ao cloreto de cálcio na manutenção da firmeza e no controle da Pectobacterium caratovorum subsp. caratovorum sobre o pimentão. O primeiro experimento foi realizado em delineamento inteiramente casualizado em esquema fatorial 4x5 com três repetições, durante 12 dias, avaliados a cada 3 dias. No segundo experimento, o ensaio foi realizado em delineamento inteiramente casualizado no esquema fatorial 5x5 com três repetições. No primeiro trabalho os frutos de pimentão foram submetidos ao método de infusão a vácuo com pressão de 200 mmHg por 5 minutos, e por seguinte avaliou-se a perda de massa fresca (PMF), firmeza do fruto (FF), cor da casca (CC), teor de sólidos solúveis (SS), pH, acidez total, (AT) e atividade de PME. No segundo ensaio os frutos de pimentão foram submetidos ao método de infusão a vácuo com pressão de 200 mmHg por cinco minutos, posteriormente os frutos foram inoculados com a Pcc em seguida realizou-se as análises de firmeza do fruto (FF), atividade de PME e a severidade da doença no pimentão (SD). Os frutos obtiveram de forma geral uma redução da firmeza ao longo do tempo em todos os tratamentos, porém foi verificado o efeito significativo na manutenção da firmeza dos frutos quando tratados em infusão a vácuo com cloreto de cálcio, não alterando as características físico-químicas, como o teor de sólidos solúveis, acidez total e atividade de PME, retardando o processo de amadurecimento do fruto. Os frutos quando tratados com infusão a vácuo com cloreto de cálcio associado à pectina metil esterase não foi favorável, pois alterou as propriedades físico-químicas do pimentão, com destaque para o declínio da firmeza, deteriorando assim a qualidade do fruto. Em relação à inoculação da Pcc no fruto, observou-se uma inibição do crescimento desse patógeno, prolongamento do fruto e uma melhor firmeza nos frutos tratados com infusão de cloreto de cálcio mais a inoculação da Pcc.
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Romanová, Kristýna. "Proteomická identifikace enzymů degradující rostlinnou biomasu". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216797.
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The theoretical part of work is focused on the issue of biomass which can be used for energy purposes, inparticular agricultural waste, as well as can serve as a substrate for biogas station. It also deals with proteomics, its goals and approaches, separation methods. The aim of this work was to measure each sample of enzyme activity of biomass, which are used as a raw materials for biogas plants and their proteomic identification.
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Delmas, Frédéric. "L'acide 3-Désoxy-D-Manno-2octulosonique 8-Phosphate (KDO-8-P) synthase chez les plantes : caractérisation fonctionnelle d'une enzyme impliquée dans la biosynthèse d'un composé pectinique des parois végétales". Bordeaux 2, 2004. http://www.theses.fr/2004BOR21104.
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Le gène KDSA code pour l'acide 3-desoxy-D-manno-octulosonique 8-phosphate (Kdo-_P) synthase qui synthétise le précurseur phosphorylé du Kdo, un constituant indispensable et indissociable de la membrane externe des bactéries à Gram négatif. Chez les plantes, le rôle du Kdo reste méconnu, mais il entre dans la composition d'un polysaccharide pectique complexe : le rhamnogalacturonane II, indispensable à la structuration du réseau de pectines de la paroi primaire. L'étude de l'enzyme KDSA a été réalisée chez la tomate (Lycopersicon esculentum Mill. ) et chez Arabidopsis thaliana. Son expression est préférentiellement associée aux cellules en division et son rôle, potentiellement associé à la biosynthèse du RG-II, serait très important puisqu'aucune plante mutante, dépourvue d'activité Kdo-8-P synthase, n'a pu être isolé. Une étude préliminaire de la Kdo transférase, enzyme terminale de la voie de biosynthèse du Kdo a aussi été réalisée et les premiers résultats seront discutésThe KDSA gene codes for the 3-deoxy-D-manno-octulosonic acid 8-phosphate (Kdo-8-P) synthase which synthesizes the phosphorylated precursor of Kdo, an essential and indissociable component of the outer membrane in Gram-negative bacteria. In plants, the role of Kdo is largely misunderstood ; however it is a constituent of a complex pectic polysaccharide : rhamnogalacturonan II, essential for the structuration of the pectin bnetwork in primary cell wall. The study of the KDSA enzyme has been performed in tomato (Lycopersicon esculentum Mill. ) and in Arabidopsis thaliana. The expression of KDSA was shown to be preferentially associated with dividing cells. Its function is thought to be of great importance since no null mutant plants, lacking the Kdo-8P synthase activity, could be isolated. A preliminary study of the Kdo transferase has been performed. This enzyme is the last one of the biosynthetic pathway of Kdo and the first results will be discussed
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Domingues, Elisa Souza. "Seleção de linhagens de leveduras pectinolíticas para fermentação de sementes de cacau (Theobroma cacao)". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-17032011-100316/.
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A qualidade das matérias-primas do chocolate depende de uma fermentação eficiente das sementes de cacau, já que é nesta etapa que ocorrem transformações bioquímicas como a liberação de aminoácidos e açúcares redutores que durante a torração irão formar os precursores do sabor do chocolate. O processo fermentativo ocorre espontaneamente e a polpa que envolve os grãos, rica em carboidratos, é o substrato para o desenvolvimento dos microrganismos fermentativos, e a atividade destes resulta na remoção da polpa com produção do mel do cacau, contribuindo para a formação dos aromas e sabores. Existem outros métodos para a retirada da polpa, estando patenteados métodos mecânicos e por ação de enzimas pectinolíticas. Contudo, a utilização dos processos mecânicos existentes não é eficiente e o uso de enzimas ainda não é economicamente viável em larga escala. A melhoria da fermentação vem sendo objeto de pesquisa e se considera que a inoculação de leveduras produtoras de pectinases durante a fermentação poderia contribuir para a eficiência do processo, com obtenção de um produto mais uniforme. Com esse objetivo, nesse trabalho, leveduras de diferentes espécies com potencial produção de enzimas pectinolíticas foram selecionadas e posteriormente avaliadas durante a fermentação e na qualidade final das amêndoas. Os dados obtidos revelaram que leveduras do gênero Kluyveromyces se mostraram as mais eficientes, mas as espécies Candida utilis e Saccharomyces cerevisiae também mostraram bons resultados, enquanto que as fermentações sem a inoculação de leveduras apresentaram baixa eficiência na produção do mel de cacau. A fermentação com K. marxianus (MMIII-41), apresentou elevação de temperatura até 34°C com queda do pH em 2,9 e coloração marrom em suas amêndoas, indicando boa qualidade, enquanto que as fermentações naturais apresentaram valores de temperatura e pH de 29°C e 3,5 e coloração amarelada em suas amêndoas devido à polpa e fibras vegetais aderidas. Durante a prova de corte, a espécie S. cerevisiae mostrou a maior quantidade de amêndoas com coloração marrom, enquanto que a espécie K. marxianus que apresentou o melhor desempenho fermentativo com degradação da fração vicilina evidenciada em gel SDS-PAGE, mostrou somente 14% de amêndoas marrons. É possível concluir que a inoculação de leveduras com produção de enzimas pectinolíticas extracelulares e o revolvimento das sementes durante a fermentação, contribui para uma maior rapidez da fermentação e melhor qualidade das amêndoas. O volume do material fermentado não permitiu alcançar as temperaturas obtidas na maior escala, mesmo assim, de acordo com os resultados obtidos nas avaliações de atividade enzimática, volumes de mel drenados, aspecto externo das sementes após 192 horas, prova de corte e degradação de vicilinas, dentre as espécies pré-selecionadas para atividade pectinolítica, as leveduras K. marxianus, Kluyveromyces fragilis, C. utilis e S. cerevisiae, revelaram, nas condições de fermentação estudadas, ter condições de trazer benefícios a qualidade das amêndoas.The quality of the raw material of chocolate depends on an efficient fermentation of cocoa beans, as it is at this stage that biochemical transformations occur as the release of amino acids and reducing sugars that during roasting will form the precursors of chocolate flavor. The fermentation process occurs spontaneously and the pulp surrounding the seeds, rich in carbohydrates, is the substrate for the development of fermentative microorganisms, and its activity results in the removal of the pulp and honey production of cocoa, contributing for the formation of aromas and flavors. There are other methods to remove the pulp, and mechanical methods being patented by the action of pectic enzymes. However, the use of existing mechanical processes is not efficient and the use of enzymes is not yet economically viable on a large scale. Improving the fermentation has been the subject of research and considered that the inoculation of yeasts producing pectinase during fermentation could contribute to the efficiency of the process, obtaining a more uniform product. With that goal in this paper, yeasts of different species with potential production of pectic enzymes were selected and then evaluated during the fermentation and the final quality of the beans. The data obtained showed that yeasts Kluyveromyces have shown the most efficient, but the species of Candida utilis and Saccharomyces cerevisiae also showed positive results, whereas the fermentation without yeast inoculation showed low efficiency in the production of honey cocoa. The fermentation with K. marxianus (MMIII-41), showed increase of temperature to 34 ° C with a pH drop to 2.9 in their brown and almonds, indicating good quality, while natural fermentations showed values of pH and temperature of 29°C and 3.5 and yellow coloring in their beans due to pulp and vegetable fibers bonded. During the test cutting, the species S. cerevisiae showed the greatest amount of almonds and brown, while the species K. marxianus which showed the best fermentation performance degradation with the vicilin fraction evidenced by SDS-PAGE, showed only 14% of brown almonds. It was concluded that inoculation with yeast production of extracellular pectic enzymes and revolving seeds during fermentation, contributing to a faster fermentation and a better quality of almonds. The volume of the fermented material is not allowed to reach temperatures obtained on the largest scale yet, according to the results obtained in the enzymatic activity, volumes of honey drained, the external appearance of the seeds after 192 hours, proof of cutting and degradation of vicilin among the species pre-selected for pectinolytic yeasts K.marxianus, Kluyveromyces fragilis, C. utilis and S. cerevisiae, revealed in fermentation conditions studied, be able to benefit the quality of the beans.
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Frouel, Stéphane. "Effets probiotiques de préparations bactériennes commerciales en aquaculture marine". Caen, 2007. http://www.theses.fr/2007CAEN2005.
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Le potentiel probiotique de préparations microbiennes commerciales basées sur 2 lactobacilles et leur milieu de culture a été testé sur les premiers stades d’animaux marins (bar Dicentrarchus labrax, crevettes Litopenaeus stylirostris, artémies Artemia salina et coquilles St Jacques Pecten maximus). In vitro, les 2 souches tolérent les conditions marines et exercent un antagonisme contre des bactéries pathogènes probablement par sécrétion d’acides organiques. In situ, cette activité a été très peu retrouvée mais ces préparations améliorent la survie de tous les animaux excepté Pecten maximus. Aussi la croissance chez les crustacés est corrélée à une augmentation des activités enzymatiques digestives (trypsine et alpha-amylase). Chez le bar, on a observé également une stimulation de la phosphatase acide et l’apparition de vésicules d’endocytose au niveau des entérocytes qui pourraient intervenir dans le système immunitaire car des effets positifs ont été notés sur quelques paramètres immuns du tissu sanguin. L’influence des produits sur la microflore n’est manifeste que chez les larves de crevettes avec une diminution des Vibrios. Les différents essais ont montré que l’activité des produits résultent plus du milieu modifié par les bactéries que des souches elles-mêmes. Aussi, un biotest développé avec Artemia salina (modèle réagissant de manière identique aux crevettes à ces produits microbiens) a permis d’initier la purification de molécules bioactives contenues dans ces produits. Deux protéines de poids moléculaires de 50 KDa et 68 KDa stimulant les activités enzymatiques digestives des artémies ont été partiellement purifiées. Leur caractérisation est en coursThe probiotic potential of commercial bacterial preparations based on 2 lactobacilli and their medium was tested on the early stages of several marine organisms (seabass Dicentrarchus labrax, shrimp Litopenaeus stylirostris, brine shrimp Artemia salina and french scallop Pecten maximus). In vitro, the 2 strains were resistant to the marine conditions and displayed a good antimicrobial activity, probably due to the secretion of organic acids. In situ, these preparations enhanced survival of all animals, except Pecten maximus. Moreover, growth of crustaceans was correlated with an increase of digestive activities (trypsin and alpha-amylase). In seabass, the acide phosphatase was also stimulated and endocytosis vesicles appeared in enterocytes. They might be involved in the stimulation of immune system because some positive effects were observed on immune parameters of blood. Bacterial microflora was changed by the products only in shrimp larvae with a decrease of vibrios. The different experiments have displayed that microbial product activity was due more to the culture media modified by lactobacilli than the strains themselves. Thus, a biotest developed with Artemia salina (which reacted of similar manner as larval shrimp to these microbial preparations), allowed to initiate the purification of the bioactive molecules contained in these products. Two proteins with respective molecular weight of 50 KDa and 68 KDa seemed to play a major role in stimulation of digestive enzymatic activity of these artemia. They were partially purified and their characterization is in progress
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Zhang, Jing. "Biochemical Study and Technical Applications of Fungal Pectinase". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6295.
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Barnavon, Laurent. "Etude d'enzymes et de l'expression des gènes correspondants impliqués ans l'évolution des polysaccharides pariétaux au cours du développement de la baie de raisin". Montpellier 2, 1999. http://www.theses.fr/1999MON20173.
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La maturite de la baie de raisin conditionne la qualite de la vendange et son aptitude a etre transformee. Les parois cellulaires du pericarpe de la baie sont responsables de la structure et de la fermete, leur evolution etant impliquee dans le ramollissement et la maturation. Des baies ont ete prelevees a douze stades de developpement depuis la periode herbacee jusqu'a la maturite technologique afin de caracteriser l'evolution de l'etat physiologique des parois. La baie d'ugni blanc suit une courbe de croissance en double sigmoide classique et elle est caracterisee par une accumulation de materiel parietal neo-synthetise quasi continue. Concernant les parois, le developpement de la baie est caracterise par une diminution importante de galactose et du degre de methylesterification (dm). Les enzymes potentiellement responsables des modifications parietales observees, ainsi que leur activite transcriptionnelle ont ete etudiees. Un clone de pectine methylesterase (pme) a ete identifie comme un marqueur precoce du ramollissement. Les activites transcriptionnelle et enzymatique de ce clone ont ete correlees a la diminution du dm des pectines parietales, suggerant un role de la pme dans l'elongation et/ou la structure des parois. Le galactose parietal, originaire des chaines laterales des pectines, diminue en accord avec l'augmentation concomitante de l'activite -galactosidase. Le transcrit codant pour cette enzyme est specifiquement exprime lors de la phase herbacee. La caracterisation moleculaire et enzymatique de la polygalacturonase (pg) semble indiquer qu'elle ne participe pas directement a la maturation. Ces travaux ont conduit a l'isolement de clones specifiques de periodes clefs du developpement de la baie de raisin. Cette etude a egalement permis de suggerer que la baie de raisin etait un modele original pour la comprehension du developpement des fruits, puisque la maturation semble independante de la pg.
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Somavat, Romel. "Applications and Effects of Ohmic Heating: Sterilization, Influence on Bacterial Spores, Enzymes, Bioactive Components and Quality Factors in Food". The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1293568724.
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Soriano, Lasheras Margarita. "Análisis de sistemas pectinolíticos bacterianos. Aislamiento y caracterización de las pectinasas PelA de "Paenibacillus" sp. BP-23 E YvpA de "Bacillus subtilis"". Doctoral thesis, Universitat de Barcelona, 2004. http://hdl.handle.net/10803/2391.
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La aplicación de enzimas en la industria constituye una de las aportaciones más recientes en las tecnologías de producción, debido a su elevada eficiencia catalítica, a que su uso no daña el medio ambiente y a su alta rentabilidad económica.En los últimos años ha aumentado de forma importante la aplicación de enzimas microbianos en la industria. La mayoría de estos enzimas son degradadores de polisacáridos de la pared celular vegetal, como celulosas, hemicelulosas y pectinas.
La pectina es un polímero formado principalmente por cadenas de ácido galacturónico, parcialmente esterificado. Las pectinasas son las enzimas que degradan la pectina.
El principal objetivo de la tesis fue caracterizar pectinasas con potencial aplicación industrial. Para ello, primero se realizó el análisis de los sistemas degradadores de pectina de las cepas bacterianas Paenibacillus sp. BP-23 y Bacillus sp. BP-7, aisladas previamente por el grupo de investigación a partir de suelo de arrozal del Delta del Ebro.
El sistema pectinolítico de ambas cepas mostró una multiplicidad de bandas, motivo por el cual, se procedió a la clonación, purificación y caracterización de pectinasas a partir de las cepas analizadas y de Bacillus subtilis 168. Los estudios realizados indican que PelA de Paenibacillus sp. BP-23 e YvpA de Bacillus subtilis son enzimas nuevos, con características diferentes a las pectato liasas conocidas, que permiten identificar un subgrupo de enzimas dentro de las pectato liasas de la familia PL3. La inusual elevada actividad sobre pectina de los dos enzimas estudiados en este trabajo los hace buenos candidatos para aplicaciones biotecnológicas relacionadas con la degradación de pectina de sustratos naturales.
En el contexto de la utilización creciente de enzimas en la industria se planteó la producción del más activo de ellos, la pectato liasa PelA, en cantidades elevadas para poder realizar ensayos de aplicación industrial, utilizando cepas huésped de Bacillus subtilis. Con este fin se construyeron vectores lanzadera que replican tanto en Bacillus subtilis como en Escherichia coli.
Los resultados obtenidos en este trabajo suponen una aproximación a la tarea de sobreproducir pectato liasas, lo que ha permitido la identificación de problemas específicos de la expresión de los enzimas en estudio y posibilitarán la construcción futura de nuevas cepas recombinantes de productividad y rendimiento aumentado.
Pectins are linear polymers of alpha-D-galacturonic acid. They are found in the middle lamella and primary cell wall of plant tissues and they are degraded by pectinases.
The aim of the thesis was the caracterization of pectinases with a potencial applications in the industry.
Therefore, we analysed the petinolytic system of the bacterial strains Paenibacillus BP-23 and Bacillus BP-7, previously isolated from a rice field.
The pectinolytic system of both strains a multiple glycanase system, some enzymes of which have been cloned and characterized.
Paenibacillus sp BP-23 PelA and Bacillus subtilis YvpA, belong to pectate lyases PL3 family, and show and unusual features among pectin and pectate lyases. For this reason, we constructed several shuttles which were used to overexpres PelA in Bacillus subtilis.
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Mano, Emy Tiyo. "Identificação de genes de Burkholderia sp. associados ao controle biológico de Pectobacterium carotovora". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/87/87131/tde-23032011-143651/.
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A bacteria Pectobacterium carotovora causa danos a diferentes hospedeiros por meio da produção de enzimas pectinolíticas que degradam o pectato de cálcio da lamela media próximo a parede celular, causando extravasamento do conteúdo celular, sintomas da podridão mole. Bactérias do gênero Burkholderia tem se mostrado capazes em controlar a podridão mole em orquídeas, no entanto, os aspectos moleculares envolvidos neste controle ainda não foram estudados. Neste trabalho, foram avaliados 602 transformantes quanto a sua habilidade em inibir os sintomas da podridão mole, onde foram observados 16 mutantes defectivos no controle da doença. Destes, foram identificados sete diferentes genes inativados pelo transposon Tn5, e estes genes podem estar envolvidos em processos de síntese de aleloquímicos, competição por nutrientes, adaptação a condições ambientais, e na interação com o hospedeiro e/ou entre microrganismos. No entanto, o envolvimento destes genes na perda da capacidade em controlar a podridão mole deve ser melhor estudado.The bacterium Pectobacterium carotovora cause damage to different hosts and by production of pectic enzymes that degrade calcium pectate of the middle lamella near of the cell wall, causing overflow of cell content and consequently the soft rot. Burkholderia genus has proven able to control the soft rot in Orchids, however, the molecular aspects involved in the control have not been studied. In this work, 602 transformants were characterized for their ability to inhibit soft rot caused by P. carotovora. We identified 16 mutants showing shifts in inhibition pattern or lost of the ablitity to inhibit soft rot symptoms. Among these mutants, we identified 7 genes related to disease inhibition,and this genes may be involved in process of allelochemicals synthesis, competition for nutrients, adapting to environmental conditions, and interaction between the host and microorganisms. However, the involvement of these genes in loss of ability to control the soft rot disease is being further studied in details.
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Albuquerque, Carolina Maria [UNESP]. "Clarificação de suco de laranja core wash por processo de flotação auxiliado por enzimas pectinolíticas e agentes clarificantes". Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/90771.
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albuquerque_cm_me_sjrp.pdf: 2192673 bytes, checksum: 95c4d486da5e0308e967a8ea5475dd6c (MD5)A recuperação dos sólidos solúveis presentes na membrana central da laranja, separada durante a etapa de extração industrial do suco, normalmente produz um suco contendo de 5 a 6ºBrix e uma série de outros compostos insolúveis (cerca de 9%), muitos dos quais contribuem para a baixa qualidade do suco, sendo responsáveis pelo amargor e adstringência. O presente trabalho propôs-se a clarificar esse suco contendo sólidos recuperados, empregando um pré-tratamento com enzimas pectinolíticas seguido por tratamento por flotação por injeção de ar comprimido auxiliada por agentes clarificantes: bentonita, sílica sol e colágeno hidrolisado. Constituíram-se os objetivos: (i) a determinação das melhores condições (tipo de enzima pectinolítica, duas hidrolases e duas pectinases, e tempo de incubação) para a degradação enzimática da pectina presente; (ii) a determinação da melhor combinação dos agentes clarificantes visando obter um subproduto clarificado através do monitoramento de parâmetros físico-químicos (capacidade floculante e transmitância) e (iii) a avaliação do processo de flotação com diferentes concentrações de bentonita (500, 1.000 e 1.500 mg L-suco-1 e pressões (490, 680 e 880 kPa) pela determinação do grau de clarificação através de monitoramento da transmitância do clarificado, pela determinação da velocidade de flotação/separação das fases, através da verificação das frações volumétricas das fases separadas (clarificado, sedimentado e flotado), em intervalos de tempos regulares durante o processo de flotação e pela análise do produto final clarificado. Os produtos clarificados foram analisados com relação ao conteúdo de sólidos solúveis e insolúveis, pH, acidez titulável, polpa, transmitância, cor (parâmetros L*, a*, b*) proteína, pectina total, sódio, hesperidina, polifenóis e bioflavonóides. Para o tratamento...
Core membrane of the orange fruit separated during the juice extraction step in the citrus processing industrial plant, is currently submitted to a soluble solids recovery process, normally producing a by product (secondary) juice containing about 5 to 6º Brix and other insoluble components (about 9%), which contribute to the juice’s low quality, since many are responsible for the bitterness and adstringency. This research aimed to clarify this by-product juice containing recovered solids, by enzyme pre-treatment with pectic enzymes, followed by a flotation treatment with compressed air injection using fining agents: bentonite, silica sol and hydrolyzed collagen. The objectives were (i) to determine the best conditions (enzyme type, two hydrolyses and two pectin-liases and incubation time) for the enzyme treatment for pectin degradation; (ii) to determine the best combination of the fining agents to obtain a clarified by-product through monitoring physical chemical parameters (flocculating ability and product transmittance); and (iii) to evaluate the flotation process and the effects of bentonite concentration (500, 1.000 and 1.500 mg L-juice-1) and saturation pressure (490, 680 and 880 kPa) by determining the degree of clarification through monitoring the product transmittance and by determining the flotation rate (and phase separation) through measurements of volumetric fractions of the separated phases (clarified, floated and sediment) over time during the flotation and phase separation processes. Both untreated and clarified juices were analyzed for soluble and insoluble solid contents, pH, total titratable acidity, pulp content, transmittance, color (parameters L*, a* and b*), protein and pectin contents, sodium, hesperidine, poliphenols and bioflavonoids. The results indicates a purified poligalacturonase as the adequate for the enzyme treatment in 1 hour, 45ºC, with 0,05 mL... (Complete abstract click electronic access below)
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Pegg, Timothy Joseph. "Cell Wall Carbohydrate Modifications during Flooding-Induced Aerenchyma Formation in Fabaceae Roots". Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1626443795433208.
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Albuquerque, Carolina Maria. "Clarificação de suco de laranja "core wash" por processo de flotação auxiliado por enzimas pectinolíticas e agentes clarificantes /". São José do Rio Preto : [s.n.], 2009. http://hdl.handle.net/11449/90771.
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Orientador: Roger Darros-BarbosaBanca: Maria Aparecida Mauro
Banca: José Fernando Durigan
Resumo: A recuperação dos sólidos solúveis presentes na membrana central da laranja, separada durante a etapa de extração industrial do suco, normalmente produz um suco contendo de 5 a 6ºBrix e uma série de outros compostos insolúveis (cerca de 9%), muitos dos quais contribuem para a baixa qualidade do suco, sendo responsáveis pelo amargor e adstringência. O presente trabalho propôs-se a clarificar esse suco contendo sólidos recuperados, empregando um pré-tratamento com enzimas pectinolíticas seguido por tratamento por flotação por injeção de ar comprimido auxiliada por agentes clarificantes: bentonita, sílica sol e colágeno hidrolisado. Constituíram-se os objetivos: (i) a determinação das melhores condições (tipo de enzima pectinolítica, duas hidrolases e duas pectinases, e tempo de incubação) para a degradação enzimática da pectina presente; (ii) a determinação da melhor combinação dos agentes clarificantes visando obter um subproduto clarificado através do monitoramento de parâmetros físico-químicos (capacidade floculante e transmitância) e (iii) a avaliação do processo de flotação com diferentes concentrações de bentonita (500, 1.000 e 1.500 mg L-suco-1 e pressões (490, 680 e 880 kPa) pela determinação do grau de clarificação através de monitoramento da transmitância do clarificado, pela determinação da velocidade de flotação/separação das fases, através da verificação das frações volumétricas das fases separadas (clarificado, sedimentado e flotado), em intervalos de tempos regulares durante o processo de flotação e pela análise do produto final clarificado. Os produtos clarificados foram analisados com relação ao conteúdo de sólidos solúveis e insolúveis, pH, acidez titulável, polpa, transmitância, cor (parâmetros L*, a*, b*) proteína, pectina total, sódio, hesperidina, polifenóis e bioflavonóides. Para o tratamento... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Core membrane of the orange fruit separated during the juice extraction step in the citrus processing industrial plant, is currently submitted to a soluble solids recovery process, normally producing a by product (secondary) juice containing about 5 to 6º Brix and other insoluble components (about 9%), which contribute to the juice's low quality, since many are responsible for the bitterness and adstringency. This research aimed to clarify this by-product juice containing recovered solids, by enzyme pre-treatment with pectic enzymes, followed by a flotation treatment with compressed air injection using fining agents: bentonite, silica sol and hydrolyzed collagen. The objectives were (i) to determine the best conditions (enzyme type, two hydrolyses and two pectin-liases and incubation time) for the enzyme treatment for pectin degradation; (ii) to determine the best combination of the fining agents to obtain a clarified by-product through monitoring physical chemical parameters (flocculating ability and product transmittance); and (iii) to evaluate the flotation process and the effects of bentonite concentration (500, 1.000 and 1.500 mg L-juice-1) and saturation pressure (490, 680 and 880 kPa) by determining the degree of clarification through monitoring the product transmittance and by determining the flotation rate (and phase separation) through measurements of volumetric fractions of the separated phases (clarified, floated and sediment) over time during the flotation and phase separation processes. Both untreated and clarified juices were analyzed for soluble and insoluble solid contents, pH, total titratable acidity, pulp content, transmittance, color (parameters L*, a* and b*), protein and pectin contents, sodium, hesperidine, poliphenols and bioflavonoids. The results indicates a purified poligalacturonase as the adequate for the enzyme treatment in 1 hour, 45ºC, with 0,05 mL... (Complete abstract click electronic access below)
Mestre
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Li, Qiao-Lin y 李巧琳. "Anti-inflammation effects of the enzyme hydrolysate of pectin". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/bny4fr.
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碩士國立屏東科技大學
食品科學系所
106
Lipopolysaccharide-induced macrophage RAW 264.7 is often used as an inflammatory response in cells. Pectin, which usually exists in citrus fruit, is composed of hetero-polysaccharides and is rich in galactose residues. It has been found that pectin treated by enzyme has the abilities of bacteriostasis, increasing emulsifying capacity and inhibiting cancer cell growth. However, pectin has anti-inflammatory effect, but the pathway of it has not been clear. Therefore, the purpose of this study was to investigate the ability and pathway of the enzyme-treated pectin to inhibit the inflammation of macrophage RAW 264.7 induced by lipopolysaccharide. Finally, the expression of NO synthase (iNOS), nitric oxide (NO), cyclooxygenase-2 (COX-2), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and tumor necrosis factor (TNF-α) were detected in the study. The results revealed that enzyme-treated pectin had no cell cytotoxicity to normal macrophage RAW 264.7 on the concentration of 0-1000 μg/ml. After cells were induced by 1 μg/ml lipopolysaccharide for 24 hours, the production of NO could be reduced through enzyme-treated pectin by 20%. In the western blot method, it was found that iNOS, COX-2, NF-κB, TNF-α and other proteins that activated NO production had a downtrend. It was found that pectin treated by enzyme had the potential to be used as a nutritional supplement to mitigate the inflammatory response.
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Huang, Ping-Hsiu y 黃評脩. "Effect of pectin enzyme treated pectin on the antioxidation capacity , emulsion stability and cancer cell growth inhibition". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/69753261471680029168.
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博士國立屏東科技大學
食品科學系所
100
Malignant tumor is the first one of the ten causes of death in the past 20 years in Taiwan. No method was found to eradicate the recurrence, aggregation or metastasis of cancer cells nowadays. Hence, the studies on innocuous components with cancer curing abilities from natural plants are valuable, practical, and academic work. Recently, a natural substance, pectin, of peel and pulp in citrus fruits such as lemon, grapefruit, orange, and tangerine, was reported to be breakdown into shorter unbranched galacturonic acid chain, modified by pH adjustment, namely modified citrus pectin (MCP) that exhibited more soluble and easier absorption by the human body. It can inhibit the adhering of cancer cell on the surface of host cells and then suppress the metastasis of cancer cells. In addition, pectin was also found to express a lot of biological activities such as metals ion removing, blood glucose reducing, cholesterol levels reducing, nitric oxide synthase (iNOS) inhibition and cyclooxygenase-2 (COX-2) inhibition for anticancer and anti-inflammation. Due to the characteristics, decomposition and modification of pectin, of pectin lyase, pectinesterase and polygalacturonase and the reaction rate of enzyme (turning over number) is greater than chemical modification. Therefore, this study will research on two part: The first part, the antioxidant activity of pectic enzyme modified pectin and to find out the best modified conditions. The second part, the inhibition of tumour cells (in vitro) by pectin enzyme treated pectin will be evaluated, the anti-tumor mechanism and anti-metastasis will be investigated as well. In antioxidant capacity: PET-pectin with 1 kDa and 11.6% DE expressed more antioxidant activity (DPPH radical scavenging activity, TEAC, and reducing power) than untreated citrus pectin (with 353 kDa and 60% DE). In addition, TEAC was found to be positively associated with mw of PET-pectin and negatively associated DE of PET-pectin. The addition of PET-pectin could increase the EA, ES, and oxidative stability of SPI-stabilized O/W emulsion. The inhibition of tumour cells (in vitro): PET-pectin was found to be absorbed by BALB/c mouse and human tumor cells and caused an increase in the membrane permeability and damage of human hepatoma HepG2, human lung carcinoma A549, and human colon carcinoma Colo 205, while the growth inhibition of human normal embryonic kidney HEK293 almost was not affected by PET-pectin. The result showed that CPE hydrolysis did increase the lipid oxidation inhibition ability, emulsion stabilizing effect, and antitumor activity of citrus pectin and can be one alternative choice of food processing for functional enhancing. Hence, the citrus PET-pectin can be considered to develop as a natural dietary supplement or food ingredient for human cancer prevention.
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Yen, Hung-Hsuan y 顏宏軒. "Pectin transacylation catalyzed by pectinesterase purified from commercial Aspergillus niger pectolytic enzyme". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/07314550515565913363.
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碩士國立屏東科技大學
食品科學系所
97
Pectinesterase (PE) will hydrolyze the methoxyl groups in the galacturonic acids of pectin to release methanol and the degree of esterification will be decreasing. Recent researches indicated that transacylation reaction occurred simultaneously when the de-esterification reaction progressed by PE through the analysis of gel permeation chromatography, viscometer and Instron etc.. The PE catalyzed the transacylation, and the new forms of ester linkages between pectin molecules also will be illustrated, and the increscent in the molecular weight of pectin in the presence of PE during incubation. Results showed that PE from Aspergillus niger remarkably conducted the transacylation that was affected by some factors, the optimal conditions for transacylation by Aspergillus niger PE were 40 ℃ and at pH 3.0~3.35 by laser particle size analysis. The transacylation catalyzed by PE from Aspergillus niger is not showed positive relation to it’s enzyme activity, the range of particle size is wide in pH 3.35 and 3.0, the pH value plays an important role in transacylation reaction.
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Lin, Wan-lin y 林宛霖. "A proteomic analysis of A549 human lung adenocarcinoma cells treated with enzyme-modified citrus pectin". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/26656153581203294197.
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碩士國立屏東科技大學
食品科學系所
101
Pectin is a form of natural saccharides existing in the cell wall of plants. In recent years numerous literatures have showed that enzyme-treated pectin could inhibit the growth of cancer cells. The objective of this research was to study the treatment of human lung adenocarcinoma cells with modified citrus pectin by using two-dimensional electrophoresis in order to separate different intracellular proteins. The protein spots obtained were then identified using mass spectrometer. The inhibition rates of human lung adenocarninoma cells and normal liver cells growth cultured by 400 ppm modified citrus pectin were about 48% and 13% respectively, as observed by MTT assay. After being treated with modified citrus pectin treatment, human lung adenocarcinoma cell showed six separated spots observed by two-dimensional electrophoresis. The proteins were identified by mass-spectrometry and found to be glycolysis proteins, gene regulation proteins and regulation of cell cycle proteins. Finally, after treated with 70μM 5-fluorouracil (anticancer drug), human lung adenocarcinoma cell showed eight separated spots observed by two-dimensional electrophoresis. The proteins found were mostly gene regulatory proteins. Moreover, regulation of apoptosis proteins, cell cycle regulatory proteins and other functional proteins were also found in the cell treated by 5-flourouracil. Keywords: modified citrus pectin, human lung adenocarcinoma cells, two-dimensional electrophoresis, mass spectrometry
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林俊甫. "Studying Delayed Fission of Pectin Esterase and Its Enzyme Dynamics from Tomato for the Effect of Magnetic Field". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/a3p5s5.
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碩士大葉大學
藥用植物與保健學系
106
Tomato belongs to the group of climacteric agricultural products and is one of the most important horticultural crops in the world However, since the respiration and ethylene produced will induce pectin esterase （PE）, polygalacturonase （PG）and cellulose（CE）reactions, resulting in the weight loss, fruit softening and oxidative damage, and thus cause the corruption of tomato. This study using the orthogonal test to discuss the optimization of the treatment conditions for maintaining the quality of tomato by using different magnetic field strength（1, 2, 3 mT）, frequency（0, 50, 100 Hz）, and pretreatment time（10, 20, 30 min）. Furthermore, the regulatory mechanism of the corruption factor of climacteric fruit by magnetic field treatment is also investigated. The results showed that the optimum conditions for the quality maintenance were at 2 mT of magnetic field strength, 50 Hz of frequency, and 10 minutes of treatment time（Weight loss：4.25％）on the 15th day of storage. Under these conditions, the result shows that the magnetic field treatment can reduce the amount of soluble solids by about 1.5 times and the acidity reduce by about 1.2 times. In addition, the magnetic field treatment can reduce 30％ carbon dioxide and 1.6 times of ethylene produced. The results also showed that the activity of PE（about 1.5 times）, PG（2.8 times）and CE .5 times）can be inhibited significantly. According to thee experimental results , the magnetic field can inhibit the respiration rate and the production of ethylene, and further inhibit the enzymatic activity of tomato, and thus delay the weight loss and tissue softening, in order to maintain the postharvest quality of tomato.
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Lee, Seung Hyae. "Biochemical and structural characterization of a novel enzyme involved in uronic acid metabolism". Thesis, 2014. http://hdl.handle.net/1828/5813.
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Polyuronic acids are an important constituent of seaweed and plants, and therefore
represent a significant part of global biomass, providing an abundant carbon source for
both terrestrial and marine heterotrophic bacteria. Through the action of polysaccharide
lyases, polyuronic acids are degraded into unsaturated monouronic acid units, which are fed into the Entner-Doudoroff pathway where they are converted into pyruvate and
glyceraldehyde-3-phosphate. The first step of this pathway was thought to occur non-
enzymatically. A highly conserved sequence, kdgF was found in alginate and pectin
utilization loci in a diverse range of prokaryotes, in proximity to well established
enzymes catalyzing steps downstream in the Entner-Doudoroff pathway and I
hypothesized that KdgF was involved in the catalysis of the first step of this pathway.
The kdgF genes from both Yersinia enterocolitica and a locally acquired Halomonas sp.
were expressed in Escherichia coli and their activity was examined using unsaturated
galacturonic acid depletion activity assays. To gain perspective on the general structure
of KdgF, x-ray crystallography was used to obtain a crystal structure of both HaKdgF
and YeKdgF. These crystal structures provided insight into the molecular details of
catalysis by the KdgF proteins, including their putative catalytic residues and a
coordinated metal binding site for substrate recognition. To elucidate amino acids that
may be involved in binding and/or catalysis, mutants were created in HaKdgF, and lack
of activity was observed in four mutants (Asp102A, Phe104A, Arg108A, and Gln55A).
The research done in this study suggests that KdgF proteins use a metal binding site
coordinated by three histidines and several additional residues to cause a change in
monouronic acid, thereby, affecting the unsaturated double bond. This suggests that
KdgF is involved in the first step in the Entner-Doudoroff pathway, which is the
linearization of unsaturated monouronic acids.Graduate
33
陳震學. "Study of pectin enzymes and rubbery banana formation". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/54679477271644144401.
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碩士國立屏東科技大學
食品科學系
90
Abstract The ripening of banana is a dynamic processing which involves many changes with component and biochemical reaction. The objective of the present study is to illustrate the relationship between pectic enzymes and occurrence of rubbery banana during ripening. The study was conducted by investigating chemical properties, specific enzyme purification and activity measurement of rubbery and normal banana fruits. Furthermore, whether the pectic enzymes play a crucial role in related to rubbery banana formation were identified. The results were summeried as follows: 1. Biochemical properties (1) The composition analysis showed that the starch content were not significantly different between rubbery and normal banana, and potassium added group (40.57%) is significantly lower than non potassium added group (45.31%). (2) The total pectin content was significantly different between normal and rubbery banana. There were: light rubbery (LR) 4.31%, medium rubbery (MR) 4.45%, heavy rubbery (HR) 4.89% and normal banana (N) 3.62%. The total pectin content is independent on potassium addition. The DE (degree of esterification) of banana are N: 65.29 %, LR: 65.83 %, MR: 66.38 % and HR: 67.14 % respectively. It revealed that the DE value increase with degree of rubbery. DE of rubbery banana is significantly higher than normal yellow banana (p<0.05). 2. Enzyme purification and activity measurement (1)Pectin enzymes: Both activity of pectinesterase (3.78 ± 0.22 units) and polygalacturonase (26.67 ± 2.34) of rubbery banana were not significantly different with those of normal banana fruits. (2) A 30 kDa polypeptide disappeared gradually with the extent of rubbiness of rubbery banana by examining protein pattern of SDS-PAGE. For polygalacturonase, no significant degradation can be observed by electrophoresis between normal and rubbery banana fruits. A consecutive purification procedure, CM-sepharose, Sephadex G-75, acidic electrophoresis and activity stain, were employed for protein identification. The purified and identified enzyme with the molecular weight of 30 kDa and pI 9.3 was identified as pectinesterase. Key words: rubbery banana, pectinesterase, polygalacturonase
34
Colangelo, Jennifer Lynn White. "Characterizing the glycosylation of pectin degrading enzymes by mass spectrometry". 1999.
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Thesis (Ph. D.)--University of Georgia, 1999.Directed by Ronald Carl Orlando. Includes articles published in Analytical chemistry, and Rapid communications in mass spectrometry, and articles submitted to Analytical chemistry, and Rapid communications in mass spectrometry. Includes bibliographical references.
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George, Helga L. "Pectic enzyme and protease production in Erwinia carotovora subsp. atroseptica /". 1987. https://scholarworks.umass.edu/theses/3399.
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HOU, Wen-Chi y 侯文琪. "I. Studies on the Linkages Between Pectin Molecules from Pea II. Studies on the Separation and Reaction Mechanisms of Pectinesterase and Pectic Acid Methylating Enzymes from Pea Plants". Thesis, 1994. http://ndltd.ncl.edu.tw/handle/10292430806861317530.
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Hou, Wen-Qi y 侯文琪. "I. Studies on the linkages between pectin molecules from pea plants II. Studies on the separation and reaction mechanisms of pectinesterase and pectic acid methylating enzymes from pea plants". Thesis, 1994. http://ndltd.ncl.edu.tw/handle/43764041293033439547.
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Carneiro, Joyce Silva. "Towards Control of Dutch Elm Disease: dsRNAs and the Regulation of Gene Expression in Ophiostoma novo-ulmi". Thesis, 2013. http://hdl.handle.net/1828/4715.
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Ophiostoma novo-ulmi is the causal agent of Dutch elm disease (DED) which has had a severe impact on the urban landscape in Canada. This research program focused on developing molecular genetic strategies to control this pathogenic fungus.
The first strategy involved the development of RNA interference (RNAi) for the down-regulation of genes involved in pathogenicity. An efficient RNAi cassette was developed to suppress the expression of the endopolygalacturonase (epg1) locus which encodes a cell-wall degrading enzyme. This epg1-RNAi cassette significantly reduced the amount of polygalacturonase activity in the fungus and resulted in almost complete degradation of epg1 mRNA. The need for a native promoter to selectively down-regulate specific gene loci was addressed by developing a carbon-catabolite regulated promoter (alcA) to drive the expression of the epg1-RNAi cassette. The expression of an alcA-driven epg1-RNAi cassette resulted in the down-regulation of epg expression under glucose starvation but normal levels of expression in high glucose. The expression could therefore be controlled by culture conditions.
The second strategy explored the potential of using dsRNA viruses to vector disruptive RNAi cassettes. An isolate of O. novo-ulmi strain 93-1224 collected in the city of Winnipeg, was infected by two dsRNA mitoviruses which upon sequence characterization were named OnuMV1c and OnuMV7.
To assess the transmissibility of this dsRNA virus the infected isolate 93-1224 was paired with three naive isolates of the related fungi O. ulmi and O. himal-ulmi. Through the use of nuclear and mitochondrial markers it was determined that the virus OnuMV1c may not rely on mitochondrial fusion for transmission but may have a cytoplasmic transmission route.
This investigation of gene expression and manipulation has provided tools to help understand gene regulation in O. novo-ulmi. It has also added to our knowledge of mitoviruses, their transmission and potential use as a biological control. By enhancing our understanding of transmissible hypovirulence this work contributes to efforts to develop a new approach to target DED as well as a potential model for the control of other fungal diseases.Graduate
0307
0306
0369
jscarneiro@hotmail.com
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CHEN, MEI-HUI y 陳美惠. "Soluble sugar content and activities of pectin metabolizing enzymes in achenes of ficus awkeotsang makino". Thesis, 1991. http://ndltd.ncl.edu.tw/handle/38311668642632771419.
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Chang, Shih-Chieh y 張世界. "Effects of color extraction methods and pectic enzyme pretreatment of must on the production of red wines". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/95594507486049855197.
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碩士國立中興大學
食品科學系
91
Abstract The red color of red wine appears attractive and brilliant due to content of anthocyanins from grape skins. In this study, the effects of coloring and flavoring matters extraction on improving red wine quality of red-wine making were examined. In addition, the effects of adding pectinase to increase the yield of must and clarification of wine were also investigated. The direct (with skin) fermentation and juice fermentation after hot extraction, and the optimal temperature of hot extraction and dosage of pectinase (Ultrazyme 100) used in the later process were studied. Different dosages(0~20ppm) of pectinase were added to the crushed, destemmed and pre-filtered must, Black Queen. After 18 hrs, the volumes and residual pectin of the filtrate by air-suction filter were measured. The volume of filtrate which 5.0ppm of pectinase added was 43.3mL/100mL, and no residual precipitated pectin was found. The crushed and destemmed must, Black Queen, was heated from 25 to 85℃ for extraction of red pigments. The absorbance at 420nm, 520nm of wave length, hue (A420/A520) and total pigments were detected, respectively. It showed that the must heated to 65℃ resulted in 0.59 of hue, and 958 mg/L (as anthocyanins) of total pigments. The red color appeared attractive and brilliant. Meanwhile, the pigments were extracted almost completely without oxidation in hot extraction process. Wines made by direct fermentation process and those by hot extraction process were assessed by sensory evaluation using 9-point scale. It showed that there were no significant differences in color, flavor, taste and overall quality of the wines. Both processes are supposed to be appropriate for red-wine making. Further analysis showed content of methanol in wine made by direct fermentation was 211.64mg/L while that made by hot extraction was 59.32mg/L. The pigment-extraction time required was 4~5 days for direct fermentation, but only several hours for hot extraction one. For the sake of low methanol or short extraction time, the hot extract process seems more appropriate to the good quality of red —wine making. Key words: Black Queen, anthocyanins , pectinase, direct (with skin) fermentation process, juice fermentation after hot extraction process, pectin, must, methanol.
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Olwoch, Ian P. "The effect of Pectinex Ultra SP-L on bacterial biofilms and human cell cultures in vitro". Thesis, 2014. http://hdl.handle.net/2263/43212.
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Biofilms are surface-bound bacterial colonies that are held together by a self-produced extracellular polymeric matrix. They are highly resistant to antibiotics and host defence mechanisms, and are known to be the cause of persistent infections. Biofilm-degrading enzymes have been shown to prevent biofilm formation, remove mature biofilm, and enhance the efficacy of antibiotics. This study investigated the antibacterial and antibiofilm actions of the commercial enzyme Pectinex Ultra SP-L (Pectinex), alone and in combination with antibiotics, on standard and clinical cultures of Staphylococcus aureus and Pseudomonas aeruginosa. The cytotoxicity of Pectinex was determined on human cell cultures in vitro.
Pectinex (7.42 – 950 PGU/ml) was not bactericidal, and had no effect on the antibacterial efficacy of amoxicillin-clavulanate and ciprofloxacin in cultures of S. aureus (ATCC 12600) and P. aeruginosa (ATCC 9027), respectively. However, in clinical cultures of P. aeruginosa, Pectinex caused an 89.0% (from 1.0 to 1.89 μg/ml) and 92.8% (from 1.67 to 3.22 μg/ml) increase in the MIC and MBC of ciprofloxacin, respectively. In clinical cultures of S. aureus, both bactericidal indices of amoxicillin-clavulanate were increased by 28.0% (from 2.0 to 2.56 μg/ml). In all bacterial cultures, low concentrations of Pectinex (≤ 118.75 PGU/ml) and prolonged incubation periods (≥ 6 h) were both associated with increased viability and biofilm biomass. Over a short incubation period (≤ 6 h), higher concentrations of Pectinex (237.5 – 950 PGU/ml) effectively inhibited biofilm formation in P. aeruginosa ATCC (237.5 – 950 PGU/ml) and clinical (950 PGU/ml) strains but not in S. aureus cultures.
Pectinex (237.5 – 950 PGU/ml) was cytotoxic to HeLa cells, lymphocytes and neutrophils, and induced morphological features that included shrunken rounded cells, blebs, apoptotic bodies, cytoplasmic vacuoles and cell debris. The effects at 475 and 950 PGU/ml were comparable to mitomycin C 10 μg/ml and staurosporine 1 μg/ml.
Pectinex was shown to either enhance or reduce biofilm biomass and cell viability in cultures of S. aureus and P. aeruginosa. The manifested effects depended on the concentration of the enzyme, the specific bacterial species and strain, and the maturity of the biofilms. Further studies are still needed in order to determine the actions of Pectinex on other clinical pathogens.Thesis (PhD)--University of Pretoria, 2014.
lk2014
Pharmacology
PhD
Unrestricted