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Queiroz, Camila Helena de Souza. "Estratégias e fisiologia do consumo e digestão de esponjas (Porifera) por Echinaster brasiliensis (Echinodermata: Asteroidea)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-24102012-085504/.
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Esponjas são sésseis e possuem um esqueleto constituído por elementos inorgânicos microscópicos (espículas), fibras de colágeno e/ou combinações destes dois componentes. Embora sem proteções físicas evidentes tais como conchas ou espinhos, são pouco predadas, sendo este fato atribuído principalmente a presença de metabólitos secundários ativos. Recentemente, um papel dos componentes esqueléticos como deterrente foi experimentalmente confirmado, mas sua importância relativa ainda é bastante debatida. Algumas estrelas-do-mar são consideradas como espongívoras, e a literatura existente geralmente coloca que a digestão é realizada externamente, sem ingestão do esqueleto da presa. Desta forma, neste trabalho foram verificados o comportamento alimentar da estrela-do-mar Echinaster brasiliensis em relação às esponjas, o destino dos componentes esqueléticos e seus efeitos na fisiologia do organismo. Observações de campo e experimentos em laboratório foram efetuados para determinar a estratégia de consumo utilizada pela estrela. O processo digestivo do material esquelético (espículas e/ou fibras) foi acompanhado até a eliminação. Foi verificado que E. brasiliensis se alimenta de diferentes espécies de esponjas, mas não consome apenas estes organismos, sendo mais generalista do que o suposto. As preferências no consumo das esponjas são determinados por fatores diversos, como a quantidade de matéria orgânica ou formato do organismo predado. A ingestão ocorre com a eversão do estômago, mas ao contrário do descrito para outras espécies, E. brasiliensis ingere componentes esqueléticos, sendo espículas encontradas inseridas no epitélio digestivo. Entretanto, essa ingestão é baixa e aparentemente não causa injúrias severas ao organismo, sendo as espículas descartadas no material fecalSponges are sessile and have a skeleton made of microscopic inorganic elements (spicules), collagen fibers and/or combinations of these two components. Although without clear physical defenses such as shells or spines, they are not preyed upon, and this is attributed mainly to the presence of active secondary metabolites. Recently, a role of skeletal components as deterrents has been experimentally confirmed, but its relative importance is still debated. Some starfishes are regarded as spongivorous, and the existing literature generally considers that the digestion is performed externally, without intake of the sponge skeleton. In this study the feeding behavior of the starfish Echinaster brasiliensis in relation to sponges, the fate of skeletal components and their effects on the starfish physiology were studied. Field observations and laboratory experiments were conducted to determine the consumption strategies used by the starfish. The digestive process of the skeletal material (spicules and/or fibers) was followed until the elimination. It was found that E. brasiliensis feeds on different species of sponges, but does not consume only these organisms, being more generalist than assumed. Preferences in the consumption of sponges were determined by several factors, such as the amount of organic matter or shape of the preyed organism. The intake occurs by the eversion of the stomach, but unlike what is described for other species E. brasiliensis ingests skeletal components, and spicules were found inserted in the digestive epithelium. However, this intake is small and apparently does not cause severe injuries to the starfishes and the spicules are discarded in fecal material
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MacDonald, Niall L. "The biochemistry of digestive enzymes in marine flatfish." Thesis, Heriot-Watt University, 1986. http://hdl.handle.net/10399/1602.
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Glass, Helen J. "Biochemical studies of digestive enzymes in marine species." Thesis, Heriot-Watt University, 1989. http://hdl.handle.net/10399/950.
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Hirschi, Karen Kemper. "Dietary and hormonal regulation of pancreatic digestive enzymes." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185333.
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The activity, synthetic rate and mRNA levels of pancreatic digestive enzymes adapt to changes in their respective dietary substrates. Previous studies in vivo implicate ketones and secretin in lipase adaptation and cholecystokinin (caerulein) in protease and, possibly, amylase adaptation. These studies were undertaken to determine the direct role(s) in vitro of these nutrient and hormonal factors on digestive enzymes in cultured rat pancreatic acinar cells. Ketones, intermediates of triglyceride metabolism, did not affect lipase activity in cells isolated from rats fed commercial non-purified diet, whether cultured in media containing high or low concentrations of glucose, a competitive energy substrate. Beta(OH)-butyrate also had no affect on lipase activity in cells from high-fat fed rats in which lipase was already elevated, but did increase lipase activity dose-dependently in cells isolated from rats fed a purified low-fat diet. Importantly, lipase levels were higher in cells from rats fed high fat diet, compared to those of low-fat fed rats, demonstrating that dietary adaptation persisted in culture. The role of ketones in lipase regulation appeared to be more complex than originally proposed, and they may not be the sole mediator. Direct effects of secretin and caerulein on the activity, secretion and relative synthesis of lipase were studied. Secretin significantly increased media lipase activity biphasically after 12 h, but had no effect on cellular lipase activity. After 24 h, secretin had no effect on lipase activity or relative synthesis of pancreatic enzymes (amylase, lipase, chymotrypsin, trypsin, elastase). In cultured cells, enzyme activities decreased over time, while media activities increased. Amylase relative synthesis decreased over time, while that of the proteases increased. Caerulein further decreased cellular content of all enzymes and increased media amylase and lipase activities. Caerulein, however, increased the relative synthesis of trypsin (p < 0.05) and chymotrypsin (p < 0.06), supporting its proposed role in protease, but not amylase, adaptation. These studies did not, however, support definitive roles of ketones or secretin in lipase regulation; perhaps they have interactive effects, or act in conjunction with other potential regulators, in the dietary adaptation of lipase.
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Ribeiro, Fernando Alberto Loforte Teixeira. "The postlarval development, growth and nutrition of the Indian white prawn Penaeus indicus (H. Milne Edwards)." Thesis, Bangor University, 1998. https://research.bangor.ac.uk/portal/en/theses/the-postlarval-development-growth-and-nutrition-of-the-indian-white-prawn-penaeus-indicus-hmilne-edwards(b7a86575-1aac-4152-a00a-5db58f5cc36d).html.
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This study investigates the postlarval development of Penaeus indicus. Particular emphasis is given to characterisation of developmental morphology, growth, ontogenetic change in digestive enzymes, and assessment of energy requirements for postlarval substages. The morphology of the Penaeus indicus postlarvae (PL) changes continuously as consecutive substages (PL1-14) were reached by daily moults. After 22 ecdyses (typically 35 days) the PL22 substage is succeeded by the adult form. Most of the morphological differentiation is observed after 2 weeks at substage PL14, but the branchiae only reach full development from substage PL16. The rostrum teeth, telson spines and ratio of body segments are important characters for identification of Penaeus indicus PL stage. Growth of PL1 postlarvae was significantly slower when fed artificial diets rather than Artemia nauplii. Similarly 14-day postlarvae which were slow developers (PL9) also grew slowly on artificial diets whereas postlarvae of the same age (substage PL14) did not show this suppression. Trypsin and amylase digestive activities increased with PL development (P<0.001) but did not change significantly (P>0.05) with diet fed. Trypsin was low during early PL stages of development and a sharp increase in tryptic activity was only observed at substage PL20 (24 mm). Amylase increased from PL1 and exceeded that of trypsin for 2-3 weeks after metamorphosis. It appears that during early stages of development postlarvae are unable to efficiently digest artificial diets due to low digestive activity. For smaller 14-day postlarvae, poor performance is possible related to a genetic regulated constraint and not to digestive capacity since enzyme levels were similar to those in larger PL14. PL1 fed for 15 days on commercially dried low-hatch decapsulated Artemia cysts showed comparable growth and survival to that of PLs fed on Artemia nauplii, but significantly higher (P<0.05) than that supported by commercial granulated and flake diets and low-hatch decapsulated cysts processed into a granulated diet or dried at 90°C. Leaching of soluble protein and carbohydrates was high for all artificial diets but low-hatch decapsulated cysts were highly stable in water. Commercially dried low-hatch cysts retain a living membrane capable of osmoregulation and retaining highly digestible nutrients important for fast growth and development of postlarvae. Survival of postlarvae was negatively correlated (P<0.05) with leaching of soluble protein, but no correlation was observed for loss of soluble carbohydrates. Daily food ingestion and routine metabolism of postlarvae increased with PL development. Food metabolism (SDA) was low for early PL stages, but increased steadily up to stage PL16 and remained the same from this substage onwards. Assimilation efficiency decreased for early PL substages and remained low up to PL13, and then increased steadily. Different energy strategies seem to be adopted during postlarval development to cope with ontogenetic modifications after metamorphosis. During early development little energy is lost in metabolism, and so more energy is converted to growth to support fast development, with increase in predatory behaviour and development of digestive system. Later more energy is lost in metabolism and committed for maintenance. The ontogenetic changes in digestive activity, energy trend and assimilation efficiency latter in PL development seems to reflect the adaptation to benthic carnivorous existence and migration of postlarvae and juveniles form inshore nursery to deeper waters. Stocking density above 20 PLs 1- reduced growth and survival but increased size variability above the inherent range, for postlarvae PL1-18 days old. However, Penaeus indicus postlarvae showed low agonistic behaviour and tolerated relatively high densities similar to that of other penaeid species, which further enhances the potential and advantages of the white prawn for culture.
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Keomanivong, Faithe Elizabeth. "The impact of digestive enzymes in the ruminant animal." Thesis, North Dakota State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10244582.
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Understanding the enzymatic activity in ruminant digestive systems is essential for securing adequate growth, reproduction and overall metabolism. In order to evaluate the impact of various nutritional sources and dietary strategies on enzymatic activity, five experiments were designed. Experiment 1 examined the influence of nutrient restriction and melatonin supplementation on maternal and fetal pancreatic development. Experiment 2 explored various phases of the reproductive cycle and the impact of intravenous arginine infusion amid differing levels of feed intake. Experiment 3 determined the effectiveness of realimentation during advancing stages of gestation. Experiments 4 and 5 examined the impact of variable rations on ruminal pH, NH3, VFA, total gas and methane concentration and enzymatic activity in steers consuming rations of fine- vs coarse-rolled corn and 20% vs 40% DDGS (Experiment 4) and corn vs barley based diets with low- vs moderate-oil DDGS (Experiment 5). Overall, nutrient restriction caused reduced BW, pancreatic mass and pancreatic enzyme activity in mature animals. In Experiment 1, the addition of dietary melatonin diminished the impact of nutrient restriction on maternal pancreatic mass and α-amylase activity while reducing the secretion of insulin and size of insulin-containing cell clusters. Fetal pancreatic enzymes were unaffected by treatment, however, pancreatic morphology exhibited greater insulin-containing cell cluster size in fetuses from adequately fed dams. In Experiment 2, arginine infusion did not alter pancreatic exocrine or endocrine function during the various luteal stage phases. In Experiment 3, realimentation during different stages of gestation decreased the impact of reduced feed intake and, in some cases, allowed for compensatory gain of the exocrine pancreas. The maternal and fetal endocrine pancreas was unaffected. Mature animals had greater changes in pancreatic exocrine secretions whereas fetuses differed mainly in endocrine function as a result of improper nutritional status. Comparison of pancreatic tissue revealed a greater quantity, and larger size, of insulin-containing cell clusters in fetuses which appear to separate as the animal matures. Differences in rumen enzymatic activity was found in Experiments 4 and 5, however, despite changes in lag time of gas production or ruminal degradation rates, the concentration of greenhouse gases (CH4 or CO2) produced were unaffected.
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Keomanivong, Faithe Elizabeth. "The Impact of Digestive Enzymes in the Ruminant Animal." Diss., North Dakota State University, 2016. https://hdl.handle.net/10365/28054.
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Understanding the enzymatic activity in ruminant digestive systems is essential for securing adequate growth, reproduction and overall metabolism. In order to evaluate the impact of various nutritional sources and dietary strategies on enzymatic activity, five experiments were designed. Experiment 1 examined the influence of nutrient restriction and melatonin supplementation on maternal and fetal pancreatic development. Experiment 2 explored various phases of the reproductive cycle and the impact of intravenous arginine infusion amid differing levels of feed intake. Experiment 3 determined the effectiveness of realimentation during advancing stages of gestation. Experiments 4 and 5 examined the impact of variable rations on ruminal pH, NH3, VFA, total gas and methane concentration and enzymatic activity in steers consuming rations of fine- vs coarse-rolled corn and 20% vs 40% DDGS (Experiment 4) and corn vs barley based diets with low- vs moderate-oil DDGS (Experiment 5). Overall, nutrient restriction caused reduced BW, pancreatic mass and pancreatic enzyme activity in mature animals. In Experiment 1, the addition of dietary melatonin diminished the impact of nutrient restriction on maternal pancreatic mass and ?-amylase activity while reducing the secretion of insulin and size of insulin-containing cell clusters. Fetal pancreatic enzymes were unaffected by treatment, however, pancreatic morphology exhibited greater insulin-containing cell cluster size in fetuses from adequately fed dams. In Experiment 2, arginine infusion did not alter pancreatic exocrine or endocrine function during the various luteal stage phases. In Experiment 3, realimentation during different stages of gestation decreased the impact of reduced feed intake and, in some cases, allowed for compensatory gain of the exocrine pancreas. The maternal and fetal endocrine pancreas was unaffected. Mature animals had greater changes in pancreatic exocrine secretions whereas fetuses differed mainly in endocrine function as a result of improper nutritional status. Comparison of pancreatic tissue revealed a greater quantity, and larger size, of insulin-containing cell clusters in fetuses which appear to separate as the animal matures. Differences in rumen enzymatic activity was found in Experiments 4 and 5, however, despite changes in lag time of gas production or ruminal degradation rates, the concentration of greenhouse gases (CH4 or CO2) produced were unaffected.
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Coll, Constans M. Gràcia. "Producció i caracterització de variants de la regió C-terminal de la ribonucleasa A. Importància d'aquesta regió sobre l'estabilitat de l'enzim." Doctoral thesis, Universitat de Girona, 2000. http://hdl.handle.net/10803/96338.
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Bovine pancreatic ribonuclease A (RNase A, EC 3.1.27.5) has been extensively studied from the structural, mechanistic and functional points of view. Within the protein folding context, it constitutes a good model of study although a rather complicated one due to the presence in the native state of four disulphide bonds and the existence of two X-proline peptide bonds in cis conformation. Most of these studies has focused on the alteration of cysteine or proline residues to study, from a kinetic point of view, the formation of the disulphide bonds or the characterization of the species present in the heterogeneous non-reduced unfolded state, respectively. In these work we have used site-directed mutagenesis to change the characteristics of a postulated chain folding initiation site (CFIS) in RNase ALa ribonucleasa A de pàncrees boví (RNasa A, EC 3.1.27.5) ha estat extensament estudiada des de punts de vista estructurals, mecanístics i funcionals. Dins del marc del plegament proteic, la RNasa A ha estat un bon model per als estudis de plegament/desplegament proteic, malgrat que força complicat a causa de la presència en l'estat natiu de quatre enllaços disulfur i l’existència de dos enllaços peptídics X-prolina en conformació cis. La major part d'aquests estudis s'han centrat en l'alteració de residus de cisteïna o de prolina per estudiar, des d'un punt de vista cinètic, la formació dels enllaços disulfur o la caracterització de les espècies presents en l'heterogeni estat desplegat de la proteïna amb els enllaços disulfur intactes, respectivament. En aquest treball hem utilitzat la mutagènesi dirigida per oligonucleòtid per canviar les característiques d'una regió de la RNasa A postulada com a iniciadora del plegament
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Samulitis, Betty Kumiko 1960. "EFFECT OF CARBOHYDRATE INTAKE ON RAT SMALL INTESTINAL DISACCHARIDASE ACTIVITIES, WITH SPECIAL RESPECT TO DIURNAL RHYTHM." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/277270.
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Aydin, Ebru. "Effects of natural products on sugar metabolism and digestive enzymes." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/10536/.
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The risk of diabetes is increasing and it is anticipated that people with diabetes will double by 2030 with about 90% of patients having type-2 diabetes. The use of herbal remedies in the treatment of diabetes has increased because of the side effects (flatulence, diarrhoea, tiredness and upset stomach) of some common drugs. To prevent or delay type-2 diabetes, the blood glucose level needs to be controlled. The objective of this research was to make a preliminary assessment of the capacity of PFS (Plant Food Supplement) extracts to reduce glucose, fructose and sucrose transport (acarbose-like activity) across the Caco-2 cell monolayers and inhibit digestive enzymes by PFS extracts. Sucrase activity is responsible for the hydrolysis of sucrose to fructose and glucose in the brush border membrane of the small intestine. Accordingly, inhibiting glucose uptake in the intestine may be beneficial for diabetic patients in controlling their blood glucose level. The initial steps of the in vitro tests development involved determining the activities of sucrase, maltase, isomaltase and human salivary α-amylase in an acetone-extract of rat intestinal tissues, improving on a previously published method by analysing glucose concentration via the hexokinase assay, and analysing the effect of PFS on sugar transporters using a previously published method using the Caco-2 cell monolayer. The literature evidence for the inhibition of cellular glucose uptake and transport by polyphenols across Caco-2 cells is limited. Also, to the best of our knowledge, this research is the first report regarding the analysis of cellular uptake and transport of 14C-sucrose and 14C-fructose using the Caco-2 cell monolayer with polyphenol-containing extracts. Additionally, 14C radioactivity was used due to its easy detection and allowed high sensitivity. Glucose, fructose and sucrose transport across the Caco-2 cell monolayer was significantly attenuated in the presence of PFS. Green tea, German chamomile and Vitis Viniferae extracts inhibited the transport of glucose, fructose and sucrose when tested independently. However, the Vitis Viniferae extracts were not able to achieve 50% inhibition for the sucrose and fructose transport. While the cellular uptake of glucose and fructose was inhibited by the PFS extracts, they were effective on the cellular uptake of sucrose. By contrast, Pelargonium and Echinacea were ineffective for both the transport and cellular uptake of sugars. Purified German chamomile and green tea extracts were found to be moderate inhibitors of α-amylase digestion of amylopectin and α-glucosidase enzymes. Due to the acarbose-like activity of the PFS extracts, they may have a potential role to reduce the risk of diabetes by inhibiting the hydrolysis of starches and reducing post-prandial blood glucose spikes. PFS may be seen as beneficial for use by diabetics as part of a nutritional intervention and in combination with exercise and drug treatment.
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Lopes, Adriana Rios. "Caracterização das tripsinas de insetos." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-28082008-095144/.
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Tripsinas são enzimas comuns à maioria dos insetos e de fundamental importância para a digestão inicial de proteínas. Desta forma, tornam-se alvos importantes para orientar a construção de plantas transgênicas resistentes a insetos. As tripsinas são serina endopeptidases que clivam cadeias protéicas na porção carboxílica de resíduos de aminoácidos básicos como lisina e arginina, sendo que a hidrólise da ligação peptídica formada por um resíduo de arginina é de duas a dez vezes mais eficiente que a hidrólise da ligação peptídica formada por lisina. A purificação das tripsinas de insetos de diferentes ordens e o estudo da especificidade de seus subsítios utilizando substratos de fluorescência apagada servem de base para a seleção de um método mais eficiente de inibição da sua atividade, assim como para desvendar as tendências evolutivas da especificidade destas enzimas. O trabalho dessa dissertação levou ao desenvolvimento de processos de purificação das tripsinas de Periplaneta americana, Tenebrio molitor, Musca domestica e Diatraea saccharalis. O estudo da especificidade dos subsítios S1, S2, S3 e S1\' das tripsinas demonstraram que, diferentemente das tripsinas dos outros insetos e das tripsinas de mamíferos, a tripsina de Diatraea saccharalis hidrolisa com maior eficiência substratos que apresentem lisina em P1, demonstrando uma diferença na especificidade primária desta enzima. Além disso, é possível verificar ao longo da evolução dos grupos de insetos estudados uma tendência a tornar os subsítios cada vez mais hidrofóbicos.Trypsins are serine endopeptidases that hydrolyze peptide bonds at the carboxyl side of positively charged residues: arginine and lysine. Mammalian trypsin preferentially cleaves the peptide bond formed by arginine. Site directed mutagenesis has shown that trypsin specificity is related to residues present at the primary specificity site and to structural determinants like two surface loops. Differences in trypsins specificity may be the cause of some insects be resistant to serine endopeptidases plant inhibitors and to Bacillus thuringiensis toxins. Trypsins are usual enzymes in insects and are very important to protein digestion. There are few studies dealing with insect trypsin specificity. They generally consist in analyses of fragments formed by the action of the enzyme on peptide chains like insulin β chain. As these studies were semi-quantitative, insect trypsin specificity requires a better characterization. This dissertation describes the purification of trypsins from Periplaneta americana, Tenebrio molitor, Musca domestica and Diatraea saccharalis and the characterization of the specificity of the subsites S1, S2, S3 e S1\' by the use of quenched fluorescence peptide substrates. The results showed that trypsins from the mentioned insects have different specificities, including the primary specificity. Thus, Diatraea saccharalis trypsin cleaves at Lys more efficiently than at Arg, whereas the eontrary is true for the other insects. The data also showed that trypsin subsites tend to beeome more hydrophobic as the insects are more evolved.
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Wood, Anna Rachel. "Secretion of digestive enzymes in the midgut of Stomoxys calcitrans L." Thesis, Bangor University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332361.
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Kapoor, Sharmila. "Investigation of nematode digestive enzymes and their inhibition in transgenic plants." Thesis, University of Bristol, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319137.
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Blakemore, Deborah. "Control of trypsin secretion in Stomoxys calcitrans." Thesis, Bangor University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387200.
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Filietáz, Carlos Felipe Tasso. "Padrões de especificidade e expressão das lipases digestivas durante o desenvolvimento e o processo infeccioso no mosquito Aedes aegypti." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/87/87131/tde-23022017-120752/.
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O mosquito Aedes aegypti é vetor de doenças como a febre amarela, dengue, chinkungunya e zika. O sistema digestório é responsável pela digestão e absorção de nutrientes, é também uma interface com o ambiente externo sendo a porta de entrada de organismos infecciosos. A presença de duas lipases digestivas foi confirmada por qPCR, uma na fase larval (L-Aa7051) e outra na fase adulta (L-Aa7055). Estas enzimas foram agrupadas na família das lipases neutras e apresentam alterações em resíduos envolvidos na especificidade, domínio tampa e alça β9. A L-Aa7055 recombinante foi expressa heterologamente em Escherichia coli na porção insolúvel, com atividade após a renaturação. Observamos que a expressão da lipase L-Aa7055 sofre uma redução de 30% na infecção Plasmodium gallinaceum, não sendo afetada pelo vírus dengue sorotipo 2 (DENV2). A digestão de lipídeos é importante na fase larval, com altos níveis de transcrito. Um estudo mais aprofundado ainda será necessário para compreender completamente o papel das lipases no processo infeccioso.The Aedes aegypti borne diseases yellow fever, dengue fever, chinkungunya and zica are important public healthy problems. The digestion and absorption of nutrients are performed in the digestive system, which is also an external environment interface that allows the infection by pathogenic microorganisms. The presence of two digestive lipases were identified by qPCR, L-Aa7051 in the larval phase and L-Aa7055 in the adult female. The lipase sequences were grouped in the neutral family, and exhibit alterations in residues involved in specificity, lid domain and β9 loop. The recombinant L-Aa7055 was expressed in the insoluble fraction, and show activity after a renaturation process. We notice that the expression levels of L-Aa7055 are reduced by 30% in the Plasmodium gallinaceum infection and were not affected by serotype 2 dengue virus (DENV2). The lipid digestion is important in the larval phase, with higher transcript levels. New studies will be necessary to the complete understanding of lipase contribution in the infectious process.
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Vigneau, Antoine John. "Digestive enzymes of the salmon louse (Lepeophtheirus salmonis) : implications for vaccine development." Thesis, University of Aberdeen, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429468.
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This study identified potential salmon louse gut antigens and determines the fate of salmon antibodies in the louse gut. The characteristics and distributions of three salmon louse (Lepeophtheirus salmonis) gut enzymes, aminopeptidase (SLAP), alkaline phosphatase (LAlkP) and β-acetyl-hexosaminidase (LHex) are described. SLAP preferred terminal methionine residue substrates and was inhibited by leuhistin, amastatin and bestatin, identifying it as an aminopeptidase N-type enzyme. Chelators inhibited SLAP activity, and Zn2+ reactivated SLAP after chelation. The enzyme was inhibited by Zn2+, Cu2+ and at 50 mM Ca2+, and activated by Mn2+ and Mg2+, SLAP activity was highest at pH 7.5 – 8.5. SLAP is a novel aminopeptidase as its activity was increased by molar concentrations of both NaC1 and KC1. The enzyme is present in soluble and membrane-associated enzyme forms. LAlkP activity was highest at pH 9 – 9.5 and required bound metal cations for catalysis with both Zn2+ and Mg2+ being able to re-activate the enzyme after chelation. LAlkP activity was also increased by molar concentrations of NaC1 and MK1. LAlkP was predominantly present as a membrane-associated enzyme. LHex activity was greatest at pH 6.5 – 7, and inhibited by N-acetyl-galactosamine and N-acetyl-glucosamine. LHex was partially inhibited by molar concentrations of NaC1, but was relatively tolerant to high salt concentrations. LHex was unaffected by chelation by EDTA. LHex was most able to resist denaturation by urea. SLAP was stabilised and activated by NaC1 and TMAO. LAlkP activity was increased by NaC1 but not by TMAO, due likely to factors not associated with stability, such as ionic forces increasing the rate of dephosphorylation. LHex was inhibited by the kosmotropic effects of both TMAO and NaC1.
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Charron, Laetitia. "Biomarqueurs énergétiques chez un amphipode d’eau douce Gammarus fossarum : Développement, lien avec le succès reproducteur et application in situ." Thesis, Reims, 2014. http://www.theses.fr/2014REIMS001/document.
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Dans le cadre de l'évaluation de la qualité des écosystèmes aquatiques, les réponses en lien avec l'énergie semblent particulièrement pertinentes pour appréhender l'état physiologique des êtres vivants et prévoir des effets populationnels. Dans ce contexte, l'objectif de ce travail a été de proposer un biomarqueur de l'assimilation de l'énergie chez un amphipode d'eau douce Gammarus fossarum. La caractérisation des activités enzymatiques digestives (amylase, cellulase et trypsine) et des réserves énergétiques (glycogène, lipides et protéines) soumises à l'influence de divers facteurs biotiques et abiotiques (sexe, stade reproducteur, température, conductivité et quantité de nourriture) a permis d'identifier l'amplitude des réponses étudiées afin d'améliorer l'interprétation des réponses obtenues en milieu naturel. Ces résultats ont également validé l'utilisation d'organismes mâles standardisés et nourris ad libitum dans le cadre d'approche active. D'autre part, la pertinence écologique des enzymes digestives en tant que biomarqueur a été évaluée en étudiant le lien existant entre une perturbation des réponses enzymatiques digestives au niveau sub-individuel et ses conséquences au niveau individuel sur le succès reproducteur des gammares. Par ailleurs, dans le cadre de deux campagnes de terrain, les mesures des activités enzymatiques digestives réalisées chez les organismes transplantés ont permis de discriminer les sites en fonction de leur qualité chimique et de proposer pour chaque marqueur une valeur référence et seuil traduisant un effet. Ainsi les activités enzymatiques digestives peuvent être utilisées comme outil pour établir un diagnostic de risque environnementalFor the assessment of the aquatic ecosystems health, responses related to energy metabolism seem particularly relevant to understanding the physiological state of living organisms and provide population- effects. In this context, the objective of this work was to propose a biomarker of energy assimilation in a freshwater amphipod Gammarus fossarum. The characterization of digestive enzymes activities ( amylase , cellulase and trypsin) and energy reserves (glycogen , lipids and proteins) submited to the influence of various biotic and abiotic factors (sex, reproductive stage , temperature, conductivity and amount of food ) determine the range of responses studied to improve the interpretation of data obtained in the field. These results can also validate the use of standardized male fed ad libitum in caging approach. On the other hand, the ecological relevance of digestive enzymes was assess, the link between digestive enzyme impairments at sub -individual level and its consequences on the fitness of the gammarid population at individual level was established. Furthermore, in the context of two field campaigns, measures of digestive enzyme activities in organisms transplanted allowed to discriminate sites according to their chemical quality and to propose for each marker a benchmarck and a threshold value reflecting an effect. Thus, digestive enzyme activities can be used as diagnostic tool for environmental risk assessment
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Rouy, Emilien. "Activité de peptides issus d’hydrolysats de protéines de lait sur la physiologie des cellules osseuses." Thesis, Paris, AgroParisTech, 2013. http://www.theses.fr/2013AGPT0085.
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L’ostéoporose touche principalement les femmes après la ménopause, c’est une maladie caractérisée par une détérioration de la minéralisation et de la micro-architecture de l’os. L’objectif du travail de thèse présenté ici est d’identifier une fraction protéique laitière ayant un effet stimulant sur la formation osseuse. Une telle fraction, ajoutée dans un produit ou un complément alimentaire, pourrait contribuer à réduire la perte osseuse. La première étape du projet consiste à produire les fractions laitières. Des protéines laitières (caséine ou protéines sériques) ont été digérées par des enzymes puis filtrées pour les fractionner selon leur poids moléculaire. Les fractions obtenues ont ensuite été testées sur des cultures primaires de cellules osseuses. Certaines fractions protéiques laitières ont augmenté la prolifération et la différenciation des ostéoblastes. Parmi ces fractions actives, la fraction correspondant au rétentat d’une filtration sur un filtre à 10kDa d’un hydrolysat de caséine par de la chymotrypsine a été sélectionnée pour être testée sur animaux. Cette fraction a été nommée fraction CR10. Pour étudier l’activité du CR10 in vivo sur le métabolisme osseux, un modèle de souris sous restriction protéique est mis au point. Nos études démontrent que, lorsque le régime est basé sur des protéines de soja, le passage d’un régime contenant 20% de protéines à un régime contenant 6% de protéines induit une réduction de la formation osseuse. Le traitement des souris sous restriction protéique avec du CR10 n’a eu aucun effet, ce qui signifie que le CR10 n’arrive pas à exercer son activité anabolique in vivo. En revanche, si de la caséine est donnée à la place du soja ou si de la PTH est injectée aux souris, la formation osseuse est augmentée. Ces résultats suggèrent que la fraction CR10 n’est pas un bon candidat comme fraction anabolique. En revanche, l’effet positif de la caséine par rapport au soja pourrait être exploité lors de futures études visant à mettre au point une fraction caséique ostéoanaboliqueOsteoporosis is a disease mainly affecting women after menopause, characterized by a reduced bone mineralization and a deterioration of bone micro-architecture. The aim of this thesis is to identify a milk protein fraction able to stimulate bone formation. When added to a food product, this fraction could reduce bone loss. The first task of this project was to produce the milk protein fractions. Milk proteins (casein or whey proteins) were digested by enzymes and fractionated by filtration according to their molecular weight. The fractions obtained were then tested on primary cultures of bone cells. Some of the milk protein fractions tested were able to increase proliferation and differentiation of osteoblasts. Among these active fractions, the one obtained by digestion of casein by chymotrypsin followed by filtration through a 10 kDa filter have been selected to be tested on animals. This fraction is named CR10. To study the activity of CR10 in vivo, a protein-restricted mouse model has been developed. Our studies showed that a reduction of protein in the diet from 20% to 6% impaired bone formation when the diet was based on soy protein. When these protein-restricted mice ingested the CR10 fraction, no improvement of the BMD was reported, which means that the CR10 cannot exert its anabolic activity in vivo. However, if casein is given instead of soy or if PTH is injected to the mice, bone formation is increased. These results suggest that the CR10 is not a good candidate as an anabolic fraction. However, the positive effect of casein compared to soy could be exploited in future studies aimed at finding an osteoanabolic casein fraction
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Xue, Xiaoming. "Enzymic studies of cellulase and xylanase from the digestive system of the redclaw crayfish Cherax quadricarinatus." Thesis, Queensland University of Technology, 1998. https://eprints.qut.edu.au/36965/1/36965_Xue_1998.pdf.
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The structural polysaccharide-degrading enzymes, cellulase and xylanase, in the digestive system of the freshwater redclaw crayfish, Cherax quadricarinatus were investigated in an attempt to elucidate the potential capacity of crayfish to utilise the cell wall components of plant material in their diet.
Cellulase, xylanase and lichenase were all found in the gastric juice, hindgut juice and hepatopancreas of the redclaw crayfish. The specific activities of cellulase and xylanase in the crayfish gastric juice were 2788 and 2060 units per ml, respectively. In contrast, cellulase and xylanase activities were only just detectable in the intestinal juice of the omnivorous Sea Garfish examined as a reference. Analysis of the relative activity of cellulase and xylanase in the different parts of the crayfish digestive tract showed that the foregut possessed total cellulase and xylanase activities 91-fold and 83-fold higher than the hindgut, respectively. This indicates that the foregut is the major organ involved in the digestion of dietary cellulose and xylan in the redclaw crayfish.
Treatment with antibiotics depressed bacterial populations in the gastric juice to very low levels, but only slightly reduced cellulase and xylanase activities. This result indicates that gastric hydrolases present in the redclaw crayfish are produced from the hepatopancreas.
Cellulase from crayfish gastric juice was active across a pH range of 4-9 with a pH optimum of 5. 5. The hepa topancreas cellulase had a similar pH profile to that found in gastric juice. The pH profile of crayfish xylanase was essentially the same as that of the cellulase. The optimum pH values for cellulase and xylanase activities in the redclaw fit well within the observed range of gastric juice pH values in this species. Crayfish cellulase was active across a temperature range of 10°C to 70°C with an optimum between 55°C and 60°C. Similarly, crayfish xylanase was active in a temperature range of 10°C to 65°C with an optimum temperature of 50°C. These results demonstrate the relatively broad stability of these enzymes across a wide range of environmental parameters.
Cellulase and xylanase activities in crayfish grown in an earthen pond were significantly lower than that of individuals raised in the laboratory and fed on a commercial pellet diet. Lower levels of cellulase and xylanase activities in the gastric juice of earthen-pond-reared crayfish were accompanied by lower levels of these enzymes in the hepatopancreas. Starvation resulted in a 2- to 3-fold reduction in gastric cellulase and xylanase activities, compared with crayfish fed on a commercial pellet diet. The significant reduction in hepatopancreatic levels of cellulase and xylanase activities was accompanied by a parallel decline in general protein content in starved crayfish, indicating a reduced level of general protein synthesis in the hepatopancreas associated with starvation.
Crayfish fed on a diet containing starch and milk (SM) had only slightly lower levels of cellulase and xylanase activities in the gastric juice, compared with a group fed on a commercial diet which contained 7% crude fibre. Cellulase levels in the hepatopancreas were also not significantly different between the two groups, although there was a significant decrease in the hepatopancreatic xylanase activity in the SM group. Cellulase and xylanase activities were significantly lower in the group fed on a starch and milk diet plus 25% fibre (cellulose and xylan) than in the commercial diet-fed crayfish. A marked decrease in the protein content of the hepatopancreas was also observed in this group. The activities of both cellulase and xylanase in juvenile crayfish (body wt. of 20-50 grams) were significantly higher (1.5-3-fold) than those of mature crayfish (body wt of 150-280 grams), indicating that the levels of these digestive enzymes may be positively related to growth rate. A positive relationship between growth rate and enzyme activity was also observed in a study using selected lines with fast growth compared with control lines. In a Gilbert River line selected for fast growth rate both the juvenile and adult crayfish possessed significantly higher cellulase and xylanase activities in gastric juice (1. 4-fold to 1. 9-fold higher) than control individuals. Similarly, higher activities (1.2-fold to 1. 7-fold higher) of both enzymes were seen in the hepatopancreas of the selected line. A parallel result (1. 3-fold to 4. 6-fold higher) was observed in selected vs control lines for Flinders River crayfish stocks.
These results suggest that redclaw crayfish produce cellulase and xylanase endogenously in the hepatopancreas, and these enzymes are secreted into the foregut of the animal. Both enzymes were present at very high levels in the gastric juice. Enzyme levels were inflated in lines selected for fast growth rate, but did not increase with increased fibre intake in the diet. The presence of high activities of these fibre-degrading enzymes in the digestive system indicates that the redclaw crayfish has a high capacity to utilise plant cell wall components. As a consequence it is suggested that addition of microbial fibredegrading enzymes to diets may not be necessary to promote crayfish growth.
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Norton, Rachel J. "Feeding and energetic relationships of Pollicipes pollicipes (Gemlin, 1790) (Cirripedia: Lepadomorpha)." Thesis, Bangor University, 1996. https://research.bangor.ac.uk/portal/en/theses/feeding-and-energetic-relationships-of-pollicipes-pollicipes-gemlin-1790-cirripedia-lepadomorpha(8123a22b-c6c6-4034-88d8-49dc203c43f6).html.
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Field and laboratory studies on the morphology, gut contents, ingestion rates and digestion efficiency of Pollicipes pollicipes were combined to obtain estimates of the likely range and quality of materials required to sustain this species . Orientation of P. pollicipes on the shores of south; west Portugal appeared to be determined by microtopography. Animals generally faced into the wave backwash. Orientation could be temporarily altered by torsion of the peduncle in response to changes in flow direction, permitting more efficient filter feeding. Cirral and mouthpart morphology suggested that P. pollicipes, Capitulum mitella and Lepas anatifera were omnivores. Size-related changes in cirral morphology made small juveniles better equipped than adults to feed on small particles. Cirral activity of P. pollicipes was investigated. Very slow rhythmic cirral extension (or 'beating') was observed in all P. pollicipes, J but only in relatively still water; once flow rates exceeded 14 cm s all barnacles exhibited prolonged cirral extension. The 'beat' rate was temperature dependent in most animals and larger animals exhibited a lower extension frequency than juveniles. It was concluded that 'beating' was primarily respiratory in function and not a feeding mechanism. The gut contents of wild P. pollicipes included animal and algal material but little inorganic matter, -.,. Small organic material predominated in small juveniles while large organic material predominated in adults. The rates of faecal production and growth were much higher in barnacles feeding on zooplankton than on algae and although algal cells were ingested in high numbers, the energy intake was so low that animals barely maintained their body weight. Digestive efficiencies varied with diet but little with barnacle size. A wide range of digestive enzymes were identified in P. pollicipes and L. anatifera suggesting that a variety of foods may be digested. Specific enzyme activity was low, characteristic of more carnivorous animals.
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Ouros, Caio César dos. "Potencial de emulsificação do resíduo do óleo de soja (goma de soja) sobre a digestibilidade de dietas com inclusão de diferentes fontes lipídicas /." Ilha Solteira, 2016. http://hdl.handle.net/11449/134239.
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Orientador: Antonio Carlos de LaurentizCo-orientador: João Martins Pizauro Junior
Banca: Alan Peres Ferraz de Melo
Banca: Andréia Fróes Galuci Oliveira de Souza
Resumo: O objetivo deste trabalho foi avaliar a viabilidade da utilização do resíduo do óleo de soja (goma de soja) como um emulsificante na dieta de frangos de corte em fase inicial (1 a 21 dias). Foram realizados dois experimentos, uma para fonte lipídica de origem vegetal (óleo de soja) e outro para fonte lipídica de origem animal (gordura suína), sendo utilizados 600 pintos de corte macho da linhagem Cobb® 500, distribuídos em um esquema fatorial (3x4) sendo três níveis de goma (0%; 1,25%; 2,5%) e quatro níveis de fonte lipídica (0%; 1,3%; 2,6%; 3,9%), totalizando em 12 tratamentos com 5 repetições para cada um dos experimentos. Foram analisados parâmetros de desempenho, coeficientes de digestibilidade e atividades de enzimas pancreáticas. No experimento onde se utilizou óleo de soja como fonte lipídica foi possível verificar melhorias de desempenho a partir dos 14 dias, e também melhora do coeficiente de digestibilidade do extrato etéreo e aumento nos níveis de energia metabolizável aparente. Quando utilizada a gordura suína como fonte lipídica não foram obtidas diferenças de desempenho relacionadas a inclusão da goma, mas foi possível observar efeitos diretos da interação da utilização da goma com a gordura nos níveis de energia metabolizável aparente
Abstract: The objective of this study was to evaluate the feasibility of using soybean oil residue (soy gum) as an emulsifier in broiler diet at an early stage (1-21 days). Two experiments were conducted, one for lipid source of vegetable (soybean oil) and one for fat source of animal origin (pork fat) and used 600 male broiler chicks of the lineage Cobb® 500, distributed in a factorial scheme (3x4) with three levels of gum (0%, 1.25%, 2.5%) and four lipid source levels (0%, 1.3%, 2.6%, 3.9%), totalizing 12 treatments with 5 replicates for each of the experiments. Performance parameters, digestibility coefficients and activities of pancreatic enzymes were analyzed. In the experiment which we used soy oil as a lipid source was possible to see performance improvements from 14 days, and also improves the digestibility coefficient of ether extract and increase the apparent metabolizable energy levels. When used in pork fat as lipid source, performance differences were not obtained related to the inclusion of soy gum, but we observed direct effects of the use of gum interaction with the fat in the apparent metabolizable energy levels
Mestre
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Berger, Eldie. "Analysis of genes and enzymes involved in the degradation of cellulose and proteins by Butyrivibrio fibrisolvens H17c." Doctoral thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/21977.
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Bibliography: pages 147-169.Butyrivibrio fibrisolvens H17c is a gram-negative obligate anaerobic bacterium found in the rumen of most ruminants. The aim of this thesis was to investigate the enzymes produced by B. fibrisolvens H17c involved in the degradation of cellulose, xylan, and protein. A library of chromosomal DNA fragments from B. fibrisolvens H17c was established in the plasmid pEcoR251, an Escherichia coli positive selection vector. The library was screened for genes expressing cellulase, xylanase, and protease activity. Two genes expressing endo-β-1,4-glucanase and cellodextrinase activity were cloned in E. coli as host. The gene expressing endo-β-1,4-glucanase activity (end1) was cloned on a recombinant plasmid pES400. The end1 gene was located on a 6.8 kb DNA fragment and expressed from its own promoter in the E. coli host. It was shown that 64% of the endoglucanase activity was located in the periplasm of the E. coli host. TnphoA mutagenesis indicated the presence of a functional E. coli-like signal peptide. The nucleotide sequence of end1 was determined and the amino acid sequence (547 amino acids) deduced. The catalytic domain of End1 showed very good similarity to the catalytic domain of the Clostridium thermoceiium EGE endoglucanase. End1 also has a non-catalytic domain similar to the binding domains of the CenA and Cex cellulases from Ceilulomonas fimi The gene expressing cellodextrinase activity (ced1) was cloned on a recombinant plasmid pES500. This gene was located on a 3.55 kb fragment and was also expressed from its own promoter in the E. coli host. The Ced1 enzyme was also exported to the periplasm of the E. coli host, but did not contain a functional E. coli-like signal peptide. The nucleotide sequence was determined and the deduced amino acid sequence (547 residues) showed high similarity to the catalytic domain of the C. thermocellum EGD endoglucanase. The proteins of End1 and Ced1 showed no similarity. The End1 and Ced1 enzymes were characterized using a range of different substrates. The End1 enzyme showed optimal activity at pH 5.6 and 45°C. Optimal activity for the Ced1 enzyme was obtained at pH 6.6 and 50°C. The proteolytic activity of B. fibrisolvens H17c was characterized using gelatin-SD5-PAGE. Ten bands of protease activity with apparent molecular weights ranging between 42 000 and 101 000 were detected at different stages during the growth cycle. The effect of protease inhibitors indicated that all ten protease bands were serine proteases. Optimal activity was observed between pH 6.0 to 7.5 and at a temperature of 50°C. The proteolytic activity of B. fibrisolvens H17c varied depending on the type of carbohydrate substrate in the medium, and was positively correlated with the growth rate.
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Trotta, Ronald. "Biological Abnormalities in the Ruminant Small Intestine and Its Relationship to Carbohydrate Assimilation." Thesis, North Dakota State University, 2019. https://hdl.handle.net/10365/31722.
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Several biological abnormalities exist between the ruminant and nonruminant small intestine and influences carbohydrate assimilation. Two experiments were conducted to identify potential mechanisms to improve carbohydrate utilization in cattle. Experiment 1 evaluated the effects of duodenal starch infusions with casein or glutamic acid on post-ruminal carbohydrase activities. Experiment 2 evaluated the effects of dietary fructose on visceral organ development and expression of nutrient transporters and digestive enzymes involved in carbohydrate assimilation. In experiment 1, the results suggest that small intestinal starch digestion may be improved in cattle with increased small intestinal flow of casein through increases in post-ruminal carbohydrase activities. In experiment 2, dietary fructose supply influenced nutrient utilization, visceral organ growth, and digestive enzyme mRNA expression and activity in neonatal calves.
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Omondi, James Gordon. "Studies on digestive enzymes from the hepatopancreas of the Indian white shrimp, Penaeus indicus." Thesis, Heriot-Watt University, 1995. http://hdl.handle.net/10399/1317.
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Edwards, M. G. "Digestive enzymes of vine weevil (Otiorhynchus sulcatus) as potential targets for insect control strategies." Thesis, Durham University, 2002. http://etheses.dur.ac.uk/4166/.
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Over the previous quarter century the vine weevil (Otiorhynchus sulcatus) has become a pest of horticultural and agricultural plants. The vine weevil is a polyphagous coleopteran insect and is able to attack over one hundred different plant species. Its spread has been limited by its lack of flight but modern world trade in live container grown plants has spread the insect to new habitats. Damage to plants caused by vine weevil is two fold, with the larvae destroying root balls while the adults attack the, leaves. The larval stage, in particular is difficult to treat with conventional insecticides unless environmentally undesirable soil treatments are used. The current lack of defence against the vine weevil has opened the door for methods of crop protection through the generation of genetically modified plants. The design of an efficient GM approach to control the vine weevil requires a sound knowledge of the insect’s digestive enzymes, which may be used as potential targets for insecticidal proteins. This approach was achieved for the vine weevil through analysis of active digestive proteases in the insects gut and the identification of suitable proteinase inhibitors which would reduce the overall level of protein hydrolysis. Using this method it was discovered that the vine weevil contained both serine and cysteine proteases in addition to a range of other digestive hydrolases. This biochemical data was supported by a molecular approach to isolate cDNA clones associated with the insect's digestive tract. Using a gut specific cDNA library clones encoding a cathepsin B protease, two trypsin proteases, a pectinesterase, a lipase and a cellulase were isolated and characterised. The cellulase isolated from vine weevil has been shown to originate from the insect genome as shown through Southern Blot analysis and sequencing across several intronic regions. Evidence presented herein shows that the vine weevil gut extract hydrolyses both cellulose and cellobiose. Similar results were observed with recombinant protein expressed in the eukaryotic yeast P.pastoris. Furthermore data presented here shows that the vine weevil has the full complement of enzymes needed for the complete digestion of crystalline cellulose, which was until recently believed to be the sole domain of several species of bacteria and yeast. In addition a cDNA clone encoded a vine weevil endogenous chitinase was isolated from the cDNA library. This chitinase cDNA and one encoding the proteinase inhibitor Oryzacystatin-I were used to generate transgenic tobacco plants which have been shown to express the transgene. These transgenic plants are the first step in developing a strategy for plant protection against vine weevil based on genetic modification.
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Su, Shengchen. "Expression of Digestive Enzymes and Nutrient Transporters in the Intestine of Eimeria-challenged Chickens." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23728.
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Avian coccidiosis is caused by the intestinal protozoa Eimeria. The parasite"s site of infection in the intestine is site specific. Eimeria acervulina infects the duodenum, E. maxima the jejunum, and E. tenella the ceca. Lesions in the intestinal mucosa cause reduced feed efficiency and body weight gain in Eimeria-challenged chickens. The growth reduction may be due to changes in expression of digestive enzymes and nutrient transporters in the intestine. The objective of this thesis was to examine the expression of digestive enzymes: APN and SI, peptide and amino acid transporters: Pept1, ASCT1, bo,+AT/rBAT, B0AT, CAT1/2, EAAT3, LAT1 and y+LAT1/2, sugar transporters: GLUT1, GLUT2, GLUT5 and SGLT1, mineral transporter: ZNT1 and an immune factor: LEAP2 in the duodenum, jejunum, ileum and ceca of Eimeria-challenged layers and broilers. Comparisons were made between E. acervulina-challenged layers and broilers and E. acervulina, E. maxima and E. tenella-challenged broilers to examine the effect of chicken breeds and Eimeria species, respectively, on digestive enzymes and nutrient transporter expression. E. acervulina-challenged layers and broilers showed downregulation of APN, bo,+AT/rBAT, B0AT, CAT2, EAAT3, GLUT2, SI, ZNT1 and LEAP2 in the duodenum, but not in the jejunum and ileum. E. acervulina-challenged duodenum, E. maxima-challenged jejunum and E. tenella-challenged ceca samples showed common downregulation of APN, GLUT5 and ZNT1. These results demonstrate that there are common changes in intestinal gene expression in response to E. acervulina in broilers and layers, and common changes in response to challenge by different Eimeria species in broilers.Master of Science
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LANDIVAR, VALVERDE MARCOS DAVID. "Isolation and characterization of cellulolytic enzymes from the digestive fluid of Rhynchophorus palmarum larvae." Doctoral thesis, Università degli studi di Ferrara, 2017. http://hdl.handle.net/11392/2488120.
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The aim of this research is the isolation and characterization of cellulolytic enzymes from the intestinal fluid of Rhynchophorus palmarum larvae. The experimental stage of this research was divided in two approaches. Initially, cellulolytic microorganisms were isolated from the digestive tract of Rhynchophorus palmarum larvae. A total of 11 bacteria and four fungi and yeast were isolated as result. Additionally, since R. palmarum is listed in the control and restriction list of the European and Mediterranean Plant Protection Organization (EPPO), it was decided to use R. ferrugineus larvae to develop the protocols for the isolation of cellulolytic microorganisms. These protocols were later replied in Ecuador with R. palmarum larvae.
Cellulolytic activity of microbial isolates was tested by staining with Congo red after incubation in a modified substrate with carboxymethylcellulose (CMC) as single source of carbon. As result, a fungus belonging to the Ascomycetes phylum, genus Thielaviopsis species ethacetica, was found to exhibit major cellulolytic activity. In addition, the influence of incubation pH and temperature on the cellulolytic activity of T. ethacetica was evaluated with a D-optimal statistical design, plotted into a response surface. It was found that T. ethacetica has a maximum cellulolytic activity when incubated at pH 4.0 and 20°C.
For the isolation of cellulolytic enzymes, T. ethacetica was incubated at pH 4.0 and 20°C. After four days the incubation broth was treated with ammonium sulfate for protein precipitation. The enzymatic crude extract was assayed in order to determine it optimal pH and temperature as well as the stability at optimized conditions. It was found that cellulolytic enzymes of T. ethacetica exhibit maximum activity at pH 4.5 and 45°C. In these conditions, cellulolytic enzymes of T. ethacetica are stable for 48 hours.Lo scopo di questa ricerca è l’isolamento e caratterizzazione di enzimi cellulosolitici dal fluido intestinale di larve di Rhynchophorus palmarum. La parte sperimentale di questa ricerca è stata divisa in due fasi. Inizialmente sono stati isolati i microrganismi presenti nel tratto digestivo di R. palmarum, dal quale sono stati isolati un totale di 11 diversi batteri e 4 tra funghi e lieviti. Dato che, il R. palmarum è inserito nella lista di controllo e restrizione della European and Mediterranean Plant Protection Organization (Eppo), è stato deciso di utilizzare le larve di R. ferrugineus, allo scopo di sviluppare i protocolli di isolamento dei microrganismi cellulosolitici. I medesimi protocolli sono stati utilizzati in Ecuador con larve di R. Palmarum. L’attività cellulosolitica di questi microrganismi è stata valutata inizialmente con un metodo qualitativo che prevede l’utilizzo di Congo red e l’incubazione dei microrganismi su terreno agarizzato contenente carbossimetil-cellulosa (CMC) come unica fonte di carbonio. Dall’analisi del microbiota, è stato selezionato un fungo appartenete al philum degli Ascomiceti, genere Thielaviopsis, specie ethacetica, nel quale è stata riscontrata la maggiore attività cellulosolitica. Successivamente, sono state valutate come le variazioni di pH e temperatura di coltura influenzano l’attività enzimatica. Questo è stato fatto adottando il metodo statistico D-optimal affiancato ad una superficie di risposta. È stato dimostrato che T. ethacetica ha il suo massimo di attività cellulosolitica a pH 4 e ad una temperatura di 20 °C. Per l’isolamento degli enzimi cellulosolitici, T. ethacetica è stato incubato in un brodo di coltura contenente CMC a pH 4 e ad una temperatura di 20 °C. Dopo 5 giorni di crescita il brodo è stato filtrato e trattato con ammonio solfato per la precipitazione proteica. L’estratto enzimatico è stato testato per determinare l’optimum di temperatura e pH e la sua stabilità in queste condizioni. È stato dimostrato che gli enzimi cellulosolitici di T. ethacetica esprimono la loro massima attività a pH4.5 e ad una temperatura di 45 °C. In queste condizioni, gli enzimi cellulosolitici di T. ethacetica sono stabili per 48 ore.
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Al-Owafeir, Mohammed. "The effects of dietary saponin and tannin on growth performance and digestion in Oreochromis niloticus and Clarias Gariepinus." Thesis, University of Stirling, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311698.
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Papoutsoglou, Eustratios Sofronios. "Comparative studies of digestive enzymes in some teleosts important for aquaculture, with particular emphasis on carbohydrases." Thesis, Heriot-Watt University, 2004. http://hdl.handle.net/10399/331.
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Speier, Jacqueline S. "Gene Expression of Nutrient Transporters and Digestive Enzymes in the Yolk Sac Membrane and Small Intestine of the Developing Embryonic Chick." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/44254.
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Chick embryos derive nutrients from the yolk during incubation and transition to intestinal absorption posthatch. Nutrient uptake is mediated by digestive enzymes and membrane bound transporter proteins. The objective of this study was to determine expression profiles of nutrient transporters and digestive enzymes during incubation in the yolk sac membrane (YSM) and small intestine of Leghorn and Cobb chickens derived from 22â 30 wk (young) and 45â 50 wk (old) breeder flocks. Genes examined included peptide transporter PepT1, amino acid transporters EAAT3, CAT1, and B0AT, monosaccharide transporters SGLT1 and GLUT5, and digestive enzymes APN and SI. Expression of these genes was measured in YSM at embryonic day (e) 11, 13, 15, 17, 19, 20, and 21 and small intestine at e15, e17, e19, e20, and e21. Absolute quantification real-time PCR assessed gene expression. PepT1, APN, and B0AT expression in YSM peaked between e15 and e17 and then decreased until e21, while expression increased over time in the small intestine. SGLT1 and EAAT3 expression increased over time in the small intestine and YSM. There was minimal gene expression of SI in the YSM, while the small intestine had high expression. GLUT5 and CAT1 expression decreased in the YSM, while peaking at e19 then decreasing in the small intestine. Breed and flock age affected expression levels in some genes. These results demonstrate that these genes show tissue- and development-specific patterns of expression and that the YSM expresses many digestive enzymes and nutrient transporters associated with the small intestine.Master of Science
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Ravipati, Dhatri. "Activity of Analogs of Anticancer Drugs on the Serine Protease Enzymes Subtilisin and Chymotrypsin." TopSCHOLAR®, 2011. http://digitalcommons.wku.edu/theses/1134.
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The anticancer activity of several platinum compounds is due to the formation of complexes with DNA. We hypothesize that the size and shape of the platinum compounds would impact interaction with proteins, and these interactions may be partly responsible for the anticancer activity. Chymotrypsin and subtilisin are serine proteases that have a histidine residue in the active site. We are investigating the inhibition of the digestive enzymes chymotrypsin and subtilisin by analogs of the anticancer drug cisplatin and trying to discern trends in the inhibition as the active site residues vary. In our research, we found that the enzyme subtilisin did not show any significant inhibition with different platinum compounds we used, while chymotrypsin showed inhibition only with the potassium tetrachloroplatinate and this inhibition is concentration dependent
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Beniers, Julian. "Enzyme localization in the digestive tract of black soldier fly larvae, by freeze-substitution and glycol methacrylate inclusion." Master's thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/69802.
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Goulart, Fernanda Rodrigues. "Farelo de linhaça in natura e demucilada como fonte proteica na dieta de juvenis de jundiá (Rhamdia quelen)." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/10793.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThis study aimed to evaluate the performance profile, digestive enzymes and metabolic effects of silver catfishes (Rhamdia quelen) in response to the partial substitution of protein source for animal protein (PB) of linseed meal in nature (FL) and demucilaged (FLD). Two hundred and forty juvenile catfish (average initial weight of 14.49 ± 1.85 g and length averaging 11.74 ± 0.61 cm) were randomly assigned to 12 cases of propylene with a working volume of 280 liters (20 fish / box) in a water recirculation system for a period of 51 days supply. During the experimental period, the water quality parameters remained within the optimum for this species. The treatments were: control diet; 17% FL (17% replacement of animal PB by PB of FL); 17%FLD (17% replacement of animal PB by PB of FLD) and 35% FLD (35 % substitution of animal PB by PB of FLD), each treatment consisted of three repetitions. The animals were fed three times daily to apparent satiation. Every 28 days samples were collected to monitor the growth. During the experimental period, growth variables (weight, total and standard length, total biomass, daily weight gain, condition factor, specific growth rate, feed conversion) and parameters of carcass (carcass yield, digestivossomático index, hepatosomatic, quotient intestinal and deposition of protein and fat) were evaluated. In addition, we determined: chemical composition (moisture, ash, fat and protein) in whole fish, blood parameters (glucose, total triglycerides, total cholesterol and total protein) in liver tissue ( glycogen, glucose, protein, free amino acids, ammonia and lactate). Activities of enzymes acid protease, amylase, trypsin and quymotripsin were also measured. The fish fed the control diet had lower levels of feed conversion (p <0.05). However, the rest of the growth parameters were not altered by the inclusion of FL and FLD. Diet 35%FLD had lower QI, moisture content, higher content of carcass fat and total fat deposited and activity of the enzyme trypsin. The blood level of triglycerides, albumin and total protein did not differ among treatments, but higher cholesterol levels (178,72 ± 10,71) and plasma glucose (62,71 ± 5,16) were found in 35%FLD treatment. The liver parameters were not affected by treatments. The composition of linseed meal after the process of demucilagen concentrated PB content and decreases to half the content of soluble fiber. Therefore, it is suggested that the FLD and FL can be used to compose part of silver catfish feed as an alternative source and cost.
Este trabalho teve por objetivo avaliar o desempenho produtivo, perfil de enzimas digestivas e efeitos metabólicos de jundiás (Rhamdia quelen) em resposta à substituição parcial da fonte proteica de origem animal pela proteína bruta (PB) dos farelos de linhaça in natura (FL) e demucilada (FLD). Duzentos e quarenta juvenis de jundiá (peso médio inicial de 14,49±1,85g e comprimento médio inicial de 11,74±0,61 cm) foram distribuídos ao acaso em 12 caixas de propileno com volume útil de 280 litros (20 peixes/caixa) em um sistema de recirculação de água por um período de sete semanas de alimentação. Durante o período experimental os parâmetros de qualidade da água mantiveram-se dentro do ideal para esta espécie. Os tratamentos avaliados foram: dieta controle; 17%FL (17% substituição da PB de origem animal pela PB do FL); 17% FLD: (17% substituição da PB de origem animal pela PB do FLD) e 35%FLD: (35% de substituição da PB de origem animal pela PB do FLD), cada tratamento consistiu de três repetições. Os animais foram alimentados três vezes ao dia, até a saciedade aparente. A cada 28 dias, foram realizadas biometrias para acompanhamento do crescimento. Durante o período experimental, foram avaliados: variáveis de crescimento (peso, comprimento total e padrão, biomassa total, ganho em peso diário, fator de condição, taxa de crescimento específico, conversão alimentar aparente) e parâmetros de carcaça (rendimento de carcaça, índices digestivossomático, hepatossomático, quociente intestinal e deposições de proteína e gordura corporal). Além disso, foram determinados: composição centesimal (umidade, cinzas, gordura e proteína) no peixe inteiro; parâmetros sangüíneos (glicose, triglicerídeos totais, colesterol total e proteínas totais) e no tecido hepático, foram determinados glicogênio, glicose, proteínas, aminoácidos livres, amônia e lactato. Também foram aferidas as atividades das enzimas protease ácida, amilase, tripsina e quimiotripsina. Os peixes alimentados com a dieta controle apresentaram menores valores de conversão alimentar (p<0,05), no entanto, o restante dos parâmetros de crescimento não foram alterados pela inclusão dos FL e FLD. A dieta 35%FLD apresentou menor QI, teor de umidade, maior teor de gordura da carcaça e gordura total depositada e atividade da enzima tripsina. Os parâmetros sanguíneos de triglicerídeos, albumina e proteínas totais não diferiram estatisticamente entre si, todavia maiores níveis de colesterol (178,72±10,71) e glicose plasmática (62,71±5,16) foram encontrados no tratamento 35%FLD. Os parâmetros hepáticos não foram afetados pelos tratamentos. A composição do farelo de linhaça após o processo de demucilagem concentrou o teor de PB e diminuiu à metade o conteúdo de fibra solúvel. Sendo assim, sugere-se que o FL e o FLD podem ser usados parcialmente para compor a ração de jundiás como fonte alternativa econômica.
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Moreira, Lílian Fernandes. "Efeito do inibidor de serino-proteases, berenil, sobre a eficiência alimentar, atividade proteolítica e desenvolvimento pós-embrionário de Anticarsia gemmatalis (Lepidoptera: Noctuidae)." Universidade Federal de Viçosa, 2007. http://locus.ufv.br/handle/123456789/3870.
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Protease inhibitors can reduce the digestive efficiency, to delay the development and to diminish the insect proteolytic activity resulting in increase of mortality through deficiency of free amino acids for maintenance of vital functions. The subject of this work were to evaluate if A. gemmatalis larvae feeding in artificial diets containing increasing concentrations of synthetic trypsin inhibitor bisbenzamidine affects negatively the insect performance, reduce the alimentary consumption, the digestibility, the assimilation efficiency of the food ingested and digested, the insect proteolytic activity and protein digestibility. To test these hypotheses were realized bioassays with individualized caterpillars and supplied daily with diets containing 0; 0,00095; 0,0019; 0,0038; 0,0076; 0,0152; 0,0304; 0,0608; 0,0912; 0,125 e 0,25% (w/w) of berenil during the entire larval phase. The digestion indices, the duration of larval phase and life cycle, the accumulated survival and the average of time survival, the pupae and adults weight, the body and wings of the adults moths were determined. Additionally, were evaluated the protein digestibility and the enzymatic activity of midgut extracts of A. gemmatalis exposed to berenil in diet, in the same concentrations above. All parameters assessed of life history were negatively affected with the increase of inhibitors in diet. Were verified an increase in the larval phase and life cycle duration, reduction in the pupae weight and body and wings length. There was reduction in the incorporated biomass and the relative growth rate. Otherwise, there were increases in ingestion, approximated digestion, and relative diet consumption rate and in the ingestion and excretion balance. The diet individual consumption increased until the 0.0076% of berenil, diminished with the increase of inhibitor concentration. The protein digestibility was directly proportional to berenil concentration while the proteolytic, amidolytic and esterolytic activities diminished with the increasing of inhibitor concentration. Therefore, albeit the berenil mixed in increasing concentrations in diet affects negatively in all life history parameters of insect, the caterpillars improve the diet intake. However, even so the total digestibility and the protein digestibility increase in higher inhibitor concentrations, the insect show lower enzymatic activity and, consequently, reduction in the efficiency in assimilation of ingested and digested food, indicating that the insect did not show adaptative mechanisms to prevent the inhibition of tripsina-like enzymes existents in your digestive tract. Thus, the berenil is a promising strategy to new studies with the subject of to synthesis mimicry peptides to apply in the field to control A. gemmatalis caterpillars in the soybean crops.
Inibidores de proteases podem reduzir a eficiência digestiva, retardar o desenvolvimento e diminuir a atividade proteolítica do inseto, resultando em aumento da mortalidade pela deficiência de aminoácidos livres para a manutenção das funções vitais. Este trabalho teve por objetivos avaliar se concentrações crescentes do inibidor sintético de serino- proteases, berenil, presente na dieta de A. gemmatalis afeta negativamente a performance do inseto, reduz o consumo alimentar, a digestibilidade e a eficiência na assimilação do alimento ingerido e digerido, reduz a atividade proteolítica e tríptica do inseto e reduz sua digestibilidade protéica. Para testar essa hipótese foram realizados bioensaios com lagartas individualizadas e alimentadas diariamente em dietas contendo 0; 0,00095; 0,0019; 0,0038; 0,0076; 0,0152; 0,0304; 0,0608; 0,0912; 0,125 e 0,25% (p/p) de berenil durante toda a fase larval. Foram determinados os índices digestórios, a duração do ciclo de vida e da fase larval, a sobrevivência acumulada e o tempo médio de vida, o peso das pupas e dos adultos, o tamanho corporal e das asas das mariposas adultas. Adicionalmente, foram avaliadas a digestibilidade protéica e a atividade enzimática de extratos do intestino médio de A. gemmatalis submetidas ao berenil na dieta, nas concentrações determinadas acima. Todos os parâmetros avaliados da história de vida do inseto foram afetados negativamente com o aumento da concentração do inibidor na dieta. Foi verificado aumento na duração da fase larval e do ciclo de vida, diminuição no peso das pupas, adultos, tamanho dos adultos e comprimento das asas. Houve redução na biomassa incorporada e na taxa relativa de crescimento. Por outro lado, houve aumento na ingestão, digestibilidade aproximada, na taxa de consumo relativa da dieta e no balanço entre ingestão e excreção das fezes. O consumo individual total da dieta aumentou até a concentração de 0,0076% do inibidor na dieta, decrescendo com o aumento da concentração de inibidor. A digestibilidade protéica foi diretamente proporcional à concentração de berenil enquanto as atividades proteolítica, amidásica e esterásica diminuíram com o aumento da concentração do inibidor. Desse modo, embora a presença de berenil em concentrações crescentes na dieta interfira negativamente em todos os parâmetros da história de vida do inseto, as lagartas respondem aumentando a ingestão da dieta. Contudo, mesmo que a digestibilidade total e a digestibilidade protéica aumentem em concentrações maiores de inibidor, o inseto apresenta menor atividade enzimática e, conseqüentemente, baixa eficiência na assimilação do alimento ingerido e digerido, indicando que o inseto não demonstra mecanismos adaptativos para impedir a inibição das enzimas tripsina-like presentes em seu sistema digestivo. Nesse sentido, o berenil surge como estratégia promissora para novos estudos visando a síntese de peptídeos miméticos para aplicação no campo como forma de controle de A. gemmatalis nos cultivos de soja.
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Lopes, Adriana Rios. "Serina endopeptidases de insetos e a interação inseto-planta." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-03102008-152123/.
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Serina endopeptidases de insetos, principalmente tripsinas e quimotripsinas, estão envolvidas na digestão inicial de proteínas. Genes codificadores para estas enzimas estão organizados em famílias multigênicas tendo expressão diferencial de acordo com a dieta do inseto, estando envolvidos no desenvolvimento de resistência a diferentes metabólitos secundários vegetais. Para uma melhor compreensão desta interação, fez-se necessário o isolamento destas enzimas para insetos de diferentes ordens, bem como a caracterização de suas especificidades por duas abordagens: (a) caracterização cinética dos subsítios componentes do sítio de ligação de tripsinas e quimotripsinas, utilizando diferentes substratos, modificadores químicos e inibidores e (b) estudos estruturais por modelagem molecular, clonagem, expressão e cristalização destas enzimas de insetos. Além disso, estudos evolutivos por análise de distância possibilitaram uma caracterização inicial da interação insetoplanta. Estas determinações permitiram verificar que tripsinas de insetos apresentam diferenças de especificidade tanto dentre as diferentes ordens de insetos quanto em relação às tripsinas de vertebrados, sendo que as tripsinas da ordem Lepidóptera apresentam troca de especificidade primária hidrolisando preferencialmente substratos P1 Lys. Foram também observadas diferenças de hidrofobicidade para os subsítios caracterizados sendo que estes apresentam hidrofobicidades crescentes segundo o grau de complexidade dos insetos na sua escala evolutiva. A troca de especificidade e o aumento da hidrofobicidade podem permitir a hidrólise dos inibidores vegetais protéicos. A análise das sequências de tripsinas de insetos por Neighbor Joining (NJ) compõe uma árvore de distâncias topologicamente semelhante à árvore de relações filogenéticas determinadas por morfologia. A sobreposição de estruturas pré -determinadas de tripsina complexada a diferentes inibidores permite a identificação de posições de interação enzima-inibidor que justificam a classificação em grupos distintos de enzimas sensíveis ou resistentes a presença de inibidores na dieta de insetos. Da mesma forma: a caracterização da especificidade das quimotripsinas de insetos permitiu a separação de grupos distintos de quimotripsinas. Estes grupos são sustentados pela substituição do resíduo 59 em insetos polífagos que alimentam-se de plantas que contêm cetonas naturais reativas. Estas caracterizações demonstram a importância de um estudo detalhado da especificidade de serina endopeptidases possibilitando o desenho de moléculas apropriadas para inibição destas e desenvolvimento de estratégias de controle de insetos.Insect serine endopeptidases, mairily trypsin and chymotrypsin are involved in initial protein digestion. Genes that encode these proteins are members of complex multigene families and are differentially expressed according to insects diet , thus being involved with resistance to plant metabolites. Purification of trypsins from different insect orders and chymotrypsins, as well as, characterization of their specificity are essential to a better understanding of this interaction. Characterization relied on two approaches: (a) kinetic characterization of the binding subsities of trypsins and chymotrypsins using different substrates, chemical modification and inhibition assays and (b) study of protein structure by molecular modelling and cloning, expression and crystallization of these enzymes. Besides that, evolutionary studies performed through distance analysis, permitted the investigation of plantinsect interaction. These characterizations showed that insect trypsins, in terms of specificity, are quite different from vertebrate trypsins and among insect orders. Lepidopterans trypsins have a distinct primary specificity, since they hydrolyses preferentially P1 Lys substrates, and present a crescent subsite hydrophobicity, which is directly correlated with the evolutionary scale. Both, the specificity exchange and the crescent hydrophobicity can allow the hydrolysis of vegetal proteic inhibitors. The analysis of trypsin sequences in Neighbor-Joining (NJ) algorithm yield a distance tree that is coherent with morphological phylogenetic relationships. The superposition of predicted structures of trypsins-inhibitors complexes permits to observe amino acid residues of interaction between enzyme-inhibitor, which support the distinction of different groups between sensitive and insensitive trypsins to the presence of inhibitors on insect diet. Similarly, characterization of insect chymotrypsins according to their specificity allowed us to classify these enzymes into different groups. These groups are supported by residue 59 replacements in polyphagous insects, which feed on plants bearing natural reactive ketones. These studies show the irnportance of a detailed study of serine endopeptidases, which may help in the development of better insect control strategies.
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Tamhane, V. A. "Identification and characterization of plant derived proteinaceous inhibitors of gut digestive enzymes of poluphagous insect pest helicoverpa armigera hubner." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2007. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2792.
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Borey, Marion. "Effets de l’alimentation végétale sur les capacités digestives de la truite arc-en-ciel et sur le microbiote associé à sa muqueuse digestive en fonction de son génotype." Thesis, Pau, 2017. http://www.theses.fr/2017PAUU3008/document.
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La pression sur les quotas de pêche et l’augmentation de la production aquacole ont contribué à une substitution importante des farines et des huiles de poisson incorporées dans les aliments pour poissons carnivores, par des farines et des huiles végétales. La truite arc-en-ciel, qui est un poisson carnivore, est affectée par ce changement de régime. Ainsi un retard de croissance apparaît dès le plus jeune stade si certaines transformations et supplémentations ne sont pas apportées aux végétaux. L’objectif de ce travail a été d’évaluer, aux stades alevins et juvéniles, l’impact d’une substitution totale des huiles et farines de poisson sur le tractus digestif de la truite arc-en-ciel, et plus particulièrement sur ses capacités digestives et sur la composition de son microbiote intestinal. Le but in fine étant de déterminer si certaines enzymes de la digestion, transporteurs intestinaux, ou sous-communautés bactériennes sont impactés par le changement de régime et peuvent expliquer le retard de croissance observé. Chacun de ces facteurs ont été étudiés via une approche de métagénomique par séquençage de nouvelle génération NGS pour la caractérisation du microbiote, et via de la PCR quantitative et des mesures d’activités enzymatiques pour la comparaison des capacités digestives. Des lignées isogéniques de truites, identifiées comme divergentes dans leur réponse à l’alimentation végétale (capables d’adaptation ou réfractaires) ont permis de disposer d’un matériel biologique pertinent pour répondre à cette question. Une modification du microbiote intestinal associé à la muqueuse digestive pourrait également contribuer à la baisse de l’homéostasie intestinale. Le changement de régime conduit en effet à une équitabilité plus faible chez les truites ayant reçue un aliment végétal, ce qui reflète un changement dans la représentativité de certains OTUs. Ce changement de régime s’est également traduit par des communautés dissimilaires en moyenne à 70 %, d’après l’estimation de la β-diversité entre les communautés de truites nourries avec l’aliment marin et celles nourries avec l’aliment végétal. La sélection opérée par l’aliment a conduit à un remplacement des OTUs rencontrés au sein des Firmicutes, c’est-à-dire que différentes espèces bactériennes de Firmicutes sont rencontrées suivant le régime considéré. La comparaison de communautés bactériennes entre les différentes lignées isogéniques a montré que la sélection opérée par le génotype de l’hôte a davantage eu lieu sur le remplacement des β-Protéobactéries. Enfin, les comparaisons d’abondances en certaines espèces bactériennes particulières suggèrent que les bactéries Cetobacterium somerae, capables de synthétiser de la vitamine B12, et Shewanella, dont l’implication dans la stimulation des cellules β du pancréas endocrine a déjà été observée chez d’autres espèces, pourraient être impliquées dans la réponse métabolique des truites aux végétaux. Les modifications identifiées dans ce travail constituent des indicateurs biologiques qui pourront être mis à profit pour évaluer la réponse du tractus digestif des truites à de nouvelles formules alimentairesOver-fishing pressure and increasing aquaculture production led to an important substitution of fish oil and fish meal with oil and meal from plant origin in feed meant for farming fish. However this replacement has some deleterious incidence on fish. For rainbow trout, which are carnivorous fish, some growth delay often appears from the early life stages when they are fed with plant based diet. The aim of this work was to assess, at alevin and juvenile stages, the impact of a total replacement of fish meal and oil on rainbow trout gastrointestinal tract, and more particularly on the digestive capacity and the associate microbiota. The objective, in fine, being to determine if some digestive enzymes, intestinal transporters, or bacterial communities are impacted by the dietary replacement and if these biological factors can be related to the observed growth delay. Metagenomic approach using next generation sequencing was used to characterize the gut bacterial communities, while digestive capacity was assessed through quantitative PCR and enzymatic measurements in order to compare rainbow trout responses to a plant-based diet. In our investigations, rainbow trout isogenic lines that diverge in their response to this alternative diet (tolerant or rather reluctant) were adopted because they constitute a pertinent biological material for answering this question.In alevin rainbow trout, a plant-based diet led to an increase of pepsinogen, trypsinogen, and chymotrypsinogen genes which codes for proteolitic enzymes. Two main assumptions can explain this response, and their effectivness remains to investigate: wether this is a physiological response due to a lower weight of trout fed with the plant-based diet, or so it is due to an increase transcritpion of pancreatic enzymes to compensate for a reduction of protein digestibility. In the intestine, it appears that an increase transcription of IAP, SGLT1, CCK-t, and PEPT1 genes, and a decrease transcription of GLUT2 gene under a plant-based diet could reflect a disability to grow under a vegetable diet.In juvenile rainbow trout, a plant-based diet led to a decrease of lipid digestibility, and of triglycerides and total amino acid plasmatic levels. These perturbations could be explained in part by a decrease of the phosphatase alkaline activity, which suggest perturbancesof intestinal homeostasis, and by a decrease of phospholipase A2 activity. Transcriptional decrease of the triglycerides transporter MTP and of the prolidase, which is a peptidase from intestinal cell cytosol, has also been observed. Some modification of the microbiota associated to the intestinal mucosa could also contribute to the decrease of the intestinal homeostasis. The dietary replacement effectively led to reduce evenness of the bacterial communities in trout fed with a plant-based diet, which reflected a shift in the representativeness of some OTUs. Bacterial community from trout fed with a marine diet and trout fed with a plant-based diet were on average 70 % dissimilar. Dietary substitution led to the replacement of OTUs from the Firmicutes class, different bacterial species being observed according to the considered diet. The comparison of bacterial community between the isogenic lines showed that the genotype led to the replacement of β-Proteobacteria. Finally, abundance comparison suggested that Cetobacterium somerae, which is able to synthesise vitamin B12, and Shewanella, which has already been reported to stimulate pancreatic β cells, could be implicated in the trout response to vegetable.Modifications observed in this work constitute biological indicator that could be used to assess the response of the digestive tract to future feed formulations
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Ribó, i. Panosa Marc. "Purificació, caracterització i clonatge de la ribonucleasa de pàncreas humà." Doctoral thesis, Universitat de Girona, 1994. http://hdl.handle.net/10803/96757.
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The answer to whether or not, human pancreatic ribonuclease may have a diagnostic value as a serum marker of pancreatic disease, depend upon the specific detection of ribonucleases originated in pancreas amogn those coexisting in serum. From our point of view, two approaches would be necessary. On one hand the characterization of the carbohydrate component of the human pancreatic ribonuclease because glycosylation is organ-specific. On the other hand, obtain monoclonal antibodies in order to specifically recognize the secretory -typeribonuclease in serum. The purification system that has been established consists of two chromatographic steps using HPLC. The first, an exchange cromatography, allows for a partial purification of ribonuclease component. The second, a reversed-phase chromatography, resolves chromatographically the human pancreatic ribonuclease heterogeneity into different fractionsLa resposta a si la ribonucleasa de pàncreas humà pot tenir algun valor diagnòstic com a marcador sèric de disfuncions pancreàtiques passa per la identificació de forma inequívoca de la ribonucleasa de pàncreas humà en sèrum. Segons el nostre enfoc, caldrien dues aproximacions, d’una banda la caracterització a nivell glucídic de la ribonucleasa de pàncreas humà, i de l’altra, el desenvolupament d’anticossos monoclonals dirigits a discriminar la ribonucleasa de tipus secretori d’entre els diferents tipus que coexisteixen en sèrum. En aquest sentit s’ha establert un sistema de purificació de la ribonucleasa pancreàtica humana que fos ràpid i repetitiu que respectés l’heterogeneïtat glucídica per a la seva posterior caracterització. El sistema de purificació establert a partir de pàncrees obtinguts a partir de donants sans d’òrgans consta de dues etapes cromatogràfiques per HPLC. La primera, una cromatografia de bescanvi catiònic, possibilita una purificació parcial, mentre la cromatografia de la fase inversa permet resoldre cromatogràficament l’heterogeneïtat de la ribonucleasa humana de pàncreas en diferents fraccions
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Miguel, Sissi. "Développement d'une nouvelle plateforme végétale de production de protéines recombinantes par l'utilisation des plantes carnivores du genre Nepenthes." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0079.
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GOUVEIA, Carolina Kropniczki. "Isolamento e identificação de bactérias de cultivo heterotrófico de Litopenaeus vannamei." Universidade Federal Pernambuco, 2012. https://repositorio.ufpe.br/handle/123456789/16009.
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A produção de camarões marinhos na região Nordeste do Brasil vem crescendo principalmente pela introdução da espécie Litopenaeus vannamei. Adicionadas à dieta ou diretamente na água, as bactérias probióticas têm sido utilizadas para controle biológico e aumento da digestibilidade alimentar e do sistema imune dos animais, elevando a lucratividade dos empreendimentos dedicados à carcinicultura. A influência de enzimas exógenas de bactérias na digestão dos camarões não está bem elucidada e ainda existe uma grande lacuna no que diz respeito a aspectos nutricionais tanto dos microrganismos, quanto dos animais cultivados. Dessa forma, objetivou-se avaliar as atividades proteolítica e amilolítica de cepas bacterianas isoladas do hepatopâncreas e estômago do L. vannamei e identificar as bactérias produtoras destas enzimas pelo sequenciamento do gene 16S rRNA. Para estudo do ambiente em tanques heterotróficos experimentais utilizando dois probióticos comerciais (HP1 e HP2) e em tanques controles heterotrófico (Het) e autotrófico (Aut), amostras de água foram tomadas ao final do experimento para contagem de bactérias heterotróficas, autotróficas e víbrios por plaqueamento em meios específicos. As médias de população bacteriana foram submetidas à análise de variância (ANOVA) complementada pelo teste de Tukey (p<0,05). Dos órgãos das amostras de camarão (n=3) foram retirados os materiais internos para isolamento das cepas bacterianas e seleção in vitro pela capacidade de produção de enzimas digestivas. Uma cepa de Bacillus subtilis (ATCC 6633) foi utilizada como testemunha na identificação utilizando os inicializadores universais para o domínio bactéria fD1 (Forward) e rD1 (Reverse). A população de bactérias heterotróficas foi mais representativa quando comparada às de autotróficas e víbrios, e o experimento Het atingiu a maior média (1,91x107 UFC/mL). As menores cargas de víbrios foram encontradas nos tanques experimentais HP1 e HP2 com médias de 2,46x104 e 2,00x104 UFC/mL, respectivamente. De 64 cepas isoladas, 11 possuíram índices enzimáticos satisfatórios (IE ≥ 2,0) para a produção de protease e amilase. Os amplicons após sequenciamento do DNA apresentaram tamanho maior que 1,4Kb e homologia com o GenBank e RDP, identificando bactérias como Bacillus subtilis e Shewanella algae. O incremento da população heterotrófica está relacionado à adição de melaço como fonte de carbono no sistema de cultivo e nos experimentos com os probióticos comerciais, a carga vibrionácea foi reduzida. A técnica de sequenciamento do gene 16S rRNA utilizando os primers fD1 e rD1 foi eficiente na caracterização bacteriana a nível de espécie e até subespécie, revelando a presença de bactérias com potencial para utilização como probiótico.
The marine shrimps cash crop in the Northeast region of Brazil is raising due to the introduction of Litopenaus vannamei. The probiotics bacteria added in the diet or directly in the water have been used for biological control and augmentations in the alimental digestibility and in the immune system, increasing the profits of enterprises related to carciniculture. The influence of bacterial exogenic enzymes on shrimp digestion is not clear and still has a gap concerning the nutrition aspects of shrimps and microorganisms. Therefore, this study had as objective the evaluations of proteolytic and amylolytic activities of bacterial strains isolated from hepatopancreas and stomach of L. vannamei and identify the bacteria responsible for enzymes production by sequencing the 16S rRNA gene. For environmental study in heterotrophic tanks using two commercial probiotics (HP1 e HP2) and in heterotrophic (Het) and autotrophic (Aut) control tanks, water samples were collected at the end of the experiment in order to count the autotrophic and heterotrophic bacteria and vibrio by plating in specific media. The means of bacterial population were submitted to variance analysis (ANOVA) and complemented by Tukey’s test (p<0.05). Internal materials were extracted from shrimp organs samples (n=3) in order to isolate the bacterial strains and “in vitro” selection due to its capacity to produce digestive enzymes. One strain of Bacillus subtilis (ATCC 6633) was used as witness on the identification using the universal primers fD1 (Forward) e rD1 (Reverse). The population of heterotrophic bacteria was more representative compared with autotrophic and vibrio population and the Het experiment presented the greatest mean (1,91x107 CFU.mL-1). The minor loads of vibrio were found in the experimental tanks HP1 and HP2 with means 2,46x104 e 2,00x104 CFU.mL-1 respectively. From sixty four strains, only eleven showed satisfactory enzymatic index (EI ≥ 2.0) to protease and amylase production. The amplicons after the DNA sequencing showed sizes bigger than 1,4Kb and homology with GenBank e RDP, identifying bacteria as Bacillus subtilis and Shewanella algae. The increment of heterotrophic population is related with the addition of molasses as carbon source in the crop system and the vibrio load were reduced in the experiments with commercial probiotics. The sequencing technique of 16S rRNA gene using fD1 and rD1 were efficient in the characterization of bacteria at the level of species and even at the level of subspecies, revealing the presence of bacteria with potential use as probiotic.
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Filgueiras, Evando Alves. "Influência de um simbiótico na qualidade do leite e no intervalo de partos de vacas leiteiras." Universidade Federal de Goiás, 2013. http://repositorio.bc.ufg.br/tede/handle/tede/3425.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Biological additives, such as probiotics, prebiotics and digestive enzymes, as well as the combination of these components - commonly called synbiotics - are an alternative to improve livestock performance. In order to evaluate the effects in dairy cattle of a synbiotic containing microencapsulated bacteria, a meta- analysis was conducted using results obtained on commercial farms. Variables included milk production and quality, and reproductive performance. Data were collected on 22 farms feeding a commercial synbiotic composed of microencapsulated probiotics, prebiotics and fibrolytic enzymes (Biofórmula Leite®). All herds followed the manufacturer's recommended dosage of 2 g / animal / day. Information was collected on bulk tank milk production and quality (Somatic Cell Count - SCC,and contents of milk fat, protein and total solids), as well as reproductive data, such as inseminations and calving dates. These data were pooled for meta-analysis, which was performed according to the mixed models procedures recommended by St. Pierre. An analysis of variance was performed, considering the farm as a random variable and treatment as a fixed effect, with time period nested within farm. For each analysis, we used the GLM procedure of Minitab (Minitab, Inc., State College, PA, USA). A probability level of 0.05% was used to determine the statistical significance of each effect. Treatment with the synbiotic produced significant reductions in bulk tank SCC(-41%) , and in calving interval (- 73 days). There was no significant effect on the contents of fat, protein, and total solids in milk. The synbiotic additive used in this study proved to be an effective tool in the reduction of somatic cells in milk, as well as improving the fertility of animals.
Os aditivos biológicos, como os probióticos, prebióticos e enzimas digestivas, ou mesmo, a combinação destes componentes, comumente denominada de simbióticos, têm se mostrado como uma alternativa para melhorar o desempenho dos animais. Com a finalidade de observar os benefícios advindos dos simbióticos com bactérias microencapsuladas em bovinos de leite, objetivou-se nessa pesquisa, realizar uma meta-análise dos resultados obtidos em nível de campo com a utilização de um produto simbiótico no desempenho produtivo, reprodutivo e na qualidade do leite de vacas leiteiras. Os dados foram coletados em 22 propriedades que utilizam o simbiótico comercial Biofórmula Leite®, composto por probióticos, prebióticos e enzimas fibrolíticas. A dosagem utilizada em todas as propriedades seguiu a indicação do fabricante de 2 g/animal/dia. Foram coletadas informações de qualidade do leite (Contagem de Células Somáticas - CCS, teores de Gordura, Proteína e Sólidos Totais), foram registradas também as médias de produção dos animais ou quantidades entregues no laticínio, bem como os dados reprodutivos, como datas das inseminações e dos partos. Esses dados foram agrupados para realização de uma meta-análise, que foi realizada de acordo com os procedimentos de modelos mistos preconizados por St. Pierre. Foi realizada uma análise de variância usando o modelo misto, considerando a fazenda como variável aleatória e o tratamento como efeito fixo, e o período aninhado na fazenda. Para cada análise, foi utilizado o procedimento GLM do Minitab (Minitab, Inc., State College, PA, EUA). O nível de probabilidade de 0,05% foi utilizado para determinar a significância estatística de cada efeito. Foi observada uma redução significativa na média de CCS dos tanques (-41%), além de uma redução de 73 dias no IP. Não foi constatado efeito significativo nos teores de gordura, proteína, e sólidos totais do leite. O aditivo simbiótico utilizado neste estudo demonstrou ser uma ferramenta eficaz na redução de células somáticas no leite, bem como na melhoria da fertilidade dos animais.
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Högberg, Ann. "Cereal non-starch polysaccharides in pig diets : influence on digestion site, gut environment and microbial populations /." Uppsala : Dept. of Animal Nutrition and Management, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/a413.pdf.
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Sitorski, Leonardo Gomes. "The Effects of Metabolizable Protein Intake and Post-Ruminal Flow of Amino Acids on Growth Performance and Pancreatic Digestive Enzymes in Steers." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/29229.
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Excessive dietary protein may affect MP use because of energetic costs of excreting excess N. Amino acids also may influence post-ruminal digestion. Therefore, two experiments were designed to evaluate the effects of MP intake and post-ruminal flow of AA on growth performance and pancreatic digestive enzymes. In experiment 1, treatments supplied different amounts of MP intake to cattle and the effects on growth performance and feeding behavior were evaluated. In experiment 2, duodenal infusion of glutamate or casein was examined and the effects on pancreatic enzymes were measured. Experiment 1 suggests that feeding steers 906 g MP/d in finishing diets supplied enough MP for the greatest growth performance and carcass characteristics. Interestingly, MP intake caused different responses on feeding behavior with greater effects on steers fed 626 and 1444 g MP/d. In experiment 2, casein infusion increased α-amylase activity but not trypsin activity. Glutamate did not influence pancreatic digestive enzymes.
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BELMONTE, Bernardo do Rego. "Determinação do potencial inseticida de extratos e lectinas de casca de cerne de Myracroduon urundeuva contra o gorgulho do milho (Stophilus zeamais)." Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/17296.
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FACEPE
Lectinas são proteínas que apresentam atividade inseticida, sendo capazes de interferir na alimentação, desenvolvimento, reprodução e sobrevivência de insetos. Sitophilus zeamais, conhecido como gorgulho-do-milho, destaca-se como uma das principais pragas de grãos armazenados no Brasil e causa danos aos grãos de milho, trigo, sorgo e arroz. Myracrodruon urundeuva (aroeira-do-sertão) é uma árvore, madeira de lei, amplamente distribuída no Brasil. O presente trabalho avaliou os efeitos deletérios de extratos e lectinas isoladas da entrecasca (MuBL) e do cerne (MuHL) de M. urundeuva sobre o gorgulho-do-milho. Para determinação da atividade inseticida, a amostra foi incorporada a discos de farinha de trigo que serviram como dieta para os insetos durante 7 dias. As faixas de concentração testadas foram: 4 a 20 mg do extrato da entrecasca por g de farinha de trigo, 14 a 70 mg/g (extrato do cerne), 0,6 a 3,0 mg/g (MuBL) e 1,4 a 7,0 mg/g (MuHL). Após o término do bioensaio, foi avaliada a taxa de mortalidade e os seguintes parâmetros nutricionais: índice de deterrência alimentar (IDA), taxa de consumo relativo (TCR), taxa de ganho relativo de biomassa (TGB) e eficiência na conversão do alimento ingerido (ECAI). Em seguida, foram realizados ensaios com o extrato da entrecasca, extrato do cerne, MuBL e MuHL em concentrações de 20 mg/g, 70 mg/g, 3 mg/g e 7 mg/g, respectivamente, e após 7 dias, extratos de intestino dos insetos foram obtidos e avaliados quanto às atividades de protease, celulases (endoglucanase, exoglucanase, β-glicosidase), fosfatases (ácida e alcalina) e α-amilase. As dietas contendo os extratos de entrecasca e do cerne não induziram mortalidade dos insetos em um período de 7 dias de experimento, bem como não exerceram efeito deterrente sobre os insetos. Contudo, ambos os extratos interferiram nos parâmetros nutricionais dos insetos. Em todos os tratamentos com os extratos houve redução da biomassa corporal, uma vez que os valores de TGB foram negativos. Os valores de ECAI também foram negativos, variando de -3% a -70%. Com relação à TCR, os valores não foram significativamente diferentes (p > 0,05) que no controle, corroborando com a ausência de efeito deterrente. A comparação entre as concentrações testadas e os valores obtidos para os parâmetros nutricionais revela que o extrato da casca foi mais efetivo que o extrato do cerne. MuBL não induziu mortalidade em 7 dias, mas afetou a incorporação da dieta pelos insetos, como evidenciado pelos valores negativos de TGB e ECAI. Os valores de TCR foram maiores que no grupo controle, indicando a ausência de efeito deterrente. MuHL apresentou efeito deterrente variando de 44,82% (fraca) a 89,65% (forte) de acordo com a concentração e afetou fortemente a nutrição dos insetos, com valores de ECAI chegando a -360%. Uma vez que todas as amostras testadas apresentaram efeitos antinutricionais, as atividades de enzimas digestivas em insetos do grupo controle e que ingeriram os extratos e as lectinas foram avaliadas. A ingestão do extrato da entrecasca não resultou em alteração significativa (p > 0,05) das atividades de protease, fosfatase ácida, fosfatase alcalina e β-glicosidase. Já as atividades de endoglucanase, exoglucanase e α-amilase foram maiores em relação ao controle. Os insetos que ingeriram o extrato do cerne apresentaram atividades de protease, endoglucanase, exoglucanase e α-amilase menores em comparação ao controle enquanto a atividade de fosfatase ácida foi maior. No tratamento com MuBL, as atividades de fosfatase ácida e α-amilase foram menores em relação ao controle. Por outro lado, as atividades de protease, endoglucanase e exoglucanase foram maiores. No tratamento com MuHL, as atividades de fosfatase alcalina, fosfatase ácida e exoglucanase foram menores em relação ao controle. Em conclusão, extratos e lectinas de entrecasca e cerne de M. urundeuva exerceram efeitos antinutricionais sobre adultos de S. zeamais, apresentando potencial para uso no controle dos danos causados por esse inseto-praga.
Lectins are proteins with insecticidal activity able to interfere with the feeding, development, reproduction and survival of insects. Sitophilus zeamais, known as maize weevil, stands out as one of the main stored grain pests in Brazil and causes damage to maize, wheat, sorghum and rice. Myracrodruon urundeuva (aroeira-do-sertão) is a hardwood tree broadly distributed in Brazil. The present work evaluated the deleterious effects of extracts and lectins isolated from the bark (MuBL) and heartwood (MuHL) of M. urundeuva against the maize weevil. For determination of insecticidal activity, the sample was incorporated into wheat flour disks that served as diet for the insects during 7 days. The concentration ranges tested were: 4–20 mg of bark extract per gram of wheat flour, 14–70 mg/g (heartwood extract), 0.6-3.0 mg/g (MuBL) and 1.4-7.0 mg/g (MuHL). After the end of bioassay, it was evaluated the mortality rate and the following nutritional parameters: feeding deterrence index (FDI), relative consumption rate (RCR), relative biomass gain rate (BGR) and efficiency in conversion of ingested food (ECIF). Next, it was performed assays with the bark extract, heartwood extract, MuBL and MuHL at concentrations of 20 mg/g, 70 mg/g, 3 mg/g and 7 mg/g, respectively, and after 7 days, extracts from insects gut were obtained and evaluated for the activities of protease, cellulases (endoglucanase, exoglucanase, β-glucosidase), phosphatases (acid and alkaline) and α-amylase. The diets containing the bark and heartwood extracts did not induce mortality of the insects in a period of 7 days of assay as well as did not exert deterrent effect on the insects. However, both extracts interfered with the nutritional parameters of the insects. In all treatments with the extracts, there was a reduction of body biomass since the values of BGR were negative. The values of ECIF were also negative, ranging from -3% to -70%. Concerning RCR, the values were not significantly (p > 0.05) from control, corroborating the absence of deterrent effect. The comparison between the tested concentrations and the values obtained for the nutritional parameters reveal that the bark extract was more effective than the heartwood extract. MuBL did not induce mortality in 7 days but affected the incorporation of the diet by the insects, as evidenced by the negative values of BGR and ECIF. The RCR values were higher than in control group indicating the absence of deterrent effect. MuHL showed deterrent effect ranging from 44.82% (weak) to 89.65% (strong) according to the concentration and affected strongly the insect nutrition, with ECIF values reaching -360%. Since all the tested samples showed antinutritional effects, the activities of digestive enzymes from insects of control group and that ingested the extracts and lectins were evaluated. The ingestion of bark extract did not result in significant alteration (p > 0.05) of the activities of protease, acid and alkaline phosphatases and β-glucosidase. However, the activities of endoglucanase, exoglucanase and α-amylase were higher concerning control. The insects that ingested the heartwood extract showed protease, endoglucanase, exoglucanase and α-amylase activities lower than in control while the activity of acid phosphatase was higher. In treatment with MuBL, the acid phosphatase and α-amylase activities were lower than in control. On the other hand, the activities of protease, endoglucanase and exoglucanase were higher. In the treatment with MuHL, the activities of alkaline and acid phosphatases and of exoglucanase were lower than in control. In conclusion, the extracts and lectins from bark and heartwood of M. urundeuva exerted antinutritional effects on S. zeamais adults, showing potential for use in control of the damages caused by this insect pest.
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Stech, Márcia Regina. "Enzimas exógenas na alimentação do cachara (Pseudoplatystoma reticulatum) /." Jaboticabal : [s.n.], 2009. http://hdl.handle.net/11449/104954.
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Resumo: Neste trabalho foi avaliado o uso de enzimas exógenas: amilase com endo-β-glucanase (AG) e fitase (Fi) em dietas para cachara (Pseudoplatystoma reticulatum). Foram realizados ensaios de digestibilidade de nutrientes de dietas contendo quatro diferentes níveis destas enzimas, em esquema fatorial 4x4. Este estudo mostrou que a adição das enzimas alteraram os valores dos coeficientes de digestibilidade aparente dos nutrientes e de absorção dos minerais. No entanto as alterações foram dependentes dos níveis utilizados, e houve interações entre os níveis das enzimas estudadas. Após, foi realizado um ensaio de desempenho com 70 dias de duração, no qual foi avaliado o efeito da ausência de enzimas ou adição de 150 mg de AG kg-1; 2.500 UF kg-1; 100 mg de AG kg-1 com 1.500 UF kg-1 em duas dietas (com 30 ou 60% da proteína de origem animal). Neste experimento, além do desempenho produtivo dos peixes, foram observadas alterações na produção endógena das enzimas digestivas; alterações histológicas do trato gastrintestinal, pâncreas e fígado; alterações na composição da carcaça; e na retenção de fósforo, cálcio e magnésio nos ossos. O sinergismo observado entre as enzimas estudadas sugere que o uso destas enzimas pode melhorar o aproveitamento das dietas para peixes carnívoros, aumentando a energia disponível, mas isto vai depender do balanceamento adequado da dieta em que são empregadas. As alterações das enzimas digestivas e histológicas observadas mostraram que as adições das enzimas exógenas avaliadas exerceram um papel importante na nutrição do cachara, no aumento do aproveitamento da proteína e dos carboidratosAbstract: This work evaluated the exogenous enzymes amylase with endo-β-glucanase (AG) and phytase (Fi) in Barred sorubim (Pseudoplatystoma reticulatum) diets. Apparent nutrients digestibility assays were done with four different enzyme levels, in a 4x4 factorial scheme. This study showed that the enzymes addition changed the nutrients apparent digestibility coefficients and the minerals absorption. However, the alterations were dependents on the levels used, and there were interactions between the evaluated enzymes levels. After, a 70 days long performance assay was done, in which was evaluated the absence or presence of 150 mg of AG.kg-1; 2,500 UF.kg-1; 100 mg of AG.kg-1 + 1,500 UF.kg-1 enzymes in two diets (30 or 60% of animal-protein). In this experiment, fish performance and alterations in the endogenous production of the digestive enzymes; histologic changes in the gastrointestinal tract, pancreas, and liver; carcass composition changes; phosphorus, calcium, and magnesium retention in the bone were observed. The synergism observed among the enzymes evaluated suggests that its use can improve the diets profit to carnivore fishes, increasing the available energy, depending on the adequate balance in each diet though. The digestive and histologic enzymes alterations observed showed that the addition of the exogenous enzymes evaluated played an important role in the Barred sorubim nutrition, in the protein and carbohydrates profit improving
Orientador: Dalton José Carneiro
Coorientador: João Martins Pizauro Júnior
Banca: Wilson Massamitu Furuya
Banca: Antonio Carlos de Laurentiz
Banca: Elisabeth Criscuolo Urbinati
Banca: Marta Verardino De Stefani
Doutor
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Dammannagoda, Acharige Lalith Keerthiratne. "An investigation of functional diversity of endogenous cellulase and expression of other digestive enzyme genes in freshwater crayfish (Cherax) species." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/75462/2/Lalith_Dammannagoda_Acharige_Thesis.pdf.
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The project evaluated potential of soluble cellulose as a cheap feed ingredient for major farmed Australian freshwater crayfish species testing their growth performance, digestive enzyme activity and digestive enzyme gene expression patterns. Test animals showed an innate capacity to utilise a range of carbohydrate sources including complex structural polysaccharides. Results suggest that more plant-derived ingredient can be incorporated in formulated low-cost feeds for the culture industry.
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Goosen, Liezel. "The effect of an exogenous fibrolytic enzyme on forage digestibility parameters." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50141.
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Thesis (MScAgric) -- Stellenbosch University, 2004.ENGLISH ABSTRACT: The ruminant has the ability to utilize forages more efficiently than any other production animal. The utilization of forage fibre is an important aspect of ruminant production systems, as this is the main source of energy available to the animal. The availability of high-fibre forage nutrients is, however, restricted by cell wall degradability, and since low quality forages contribute a great deal to ruminant production systems worldwide, the improvement of this degradation process is of major economic importance. The use of exogenous fibre degrading enzymes has been proposed as a means of enhancing this process, with positive results being obtained from in vitro studies incorporating exogenous enzyme preparations. Positive in vivo results with regard to forage digestibility and other animal production parameters have consequently also been obtained following the addition of exogenous fibre-degrading enzyme preparations to the ruminant diet. Two initial screening experiments were undertaken in order to identify fungal enzyme preparations that may have a positive effect on in vitro fibre degradability. The initial screening employed an in vitro organic matter digestibility technique, and was successful in identifying at least six enzyme preparations displaying enhanced digestibility results that were statistically significant. A second in vitro gas production procedure was used to confirm results obtained from organic matter digestibility assays, as well as to increase screening capacity in order to evaluate new enzyme preparations more time-efficiently. Statistical analysis of results obtained from the secondary screening identified various enzyme candidates producing promising results. Only one of these, Abo 374, proved to be statistically superior to the control and other enzyme preparations. A growth trial was subsequently conducted to assess the performance of this enzyme in vivo. The trial involved individual feeding of 32 Dohne Merino ram lambs grouped according to weights into four groups consisting of 8 lambs each. Each group represented a specific application level of enzyme to the wheat straw component of a high fibre diet, amounting to 10, 5, or 1 ml enzyme supematant/kg straw. The enzyme was diluted with water at appropriate rates to obtain an application rate of 300ml/kg straw. The fourth (control) group was treated with water at the same application rate. The trial was conducted over a period of six weeks, during which feed intakes, weekly weight gains, as well as feed conversion efficiencies were recorded. Results suggested significant weight gains in the high (10ml/kg) and medium (5ml/kg) treatment groups, indicated by a P-value of 0.04. Similarly, feed conversion efficiencies were improved for above-mentioned groups (P=0.05), while feed intakes did not differ significantly between the four experimental groups.
AFRIKAANSE OPSOMMING: Die herkouer besit die vermoee om ruvoere beter as enige ander produksiedier te kan benut. Die gebruik van ruvoervesel is 'n belangrike aspek van herkouer produksiesisteme, aangesien ruvoere die hoof bron van energie aan die herkouer verskaf. Die beskikbaarheid van hoe-vesel ruvoer nutriente word egter beperk deur die degradeerbaarheid van die selwand, en aangesien lae kwaliteit ruvoere 'n groot bydrae tot wereldwye herkouer-produksiesisteme maak, is die moontlike verbetering van hierdie degraderingsproses van groot ekonomiese belang. In 'n poging om hierdie verteringsproses te help bevoordeel, is die gebruik van eksogene veselverterende ensieme ondersoek, en positiewe resultate is verkry wanneer hierdie ensieme in in vitro studies gebruik is. Goeie verbeterings ten opsigte van ruvoer verteerbaarheid en ander diereproduksie parameters is ook verkry deur middel van in vivo studies waar eksogene ensieme by die ruvoer van herkouers gevoeg IS. Twee eksperimente is ondemeem in 'n poging om ensiempreparate wat 'n moontlike positiewe effek op in vitro veselvertering mag he, te identifiseer. Die eerste, 'n in vitro organiese materiaal verteerbaarheid tegniek, was suksesvol in die identifisering van minstens ses ensiem preparate wat statisties betekenisvolle verbeterings ten opsigte van verteringsresultate geproduseer het. 'n Tweede in vitro gasproduksie prosedure is vervolgens gebruik om resultate verkry vanaf die eerste tegniek, te bevestig, asook om evalueringskapasiteit te vergroot en sodoende, nuwe ensiempreparate meer tydseffektief te evalueer. Statistiese evaluering van resultate verkry uit die tweede in vitro tegniek het 'n reeks ensieme met positiewe resultate opgelewer. Een van hierdie, Ab0374, het statisties betekenisvolle resultate ten opsigte van die kontrole, sowel as ander ensieme getoon. In 'n volgende eksperiment is 'n groeiproef gedoen om die effektiwiteit van hierdie ensiem in vivo te toets. In die proef is 32 Dohne Merino ramlammers op grond van hul gewig in vier groepe van agt skape elk verdeel, en individueel gevoer. Die groepe het verskillende toedieningsvlakke van die toetsensiem, toegedien tot die koringstrooi komponent van 'n hoe-vesel dieet, ontvang. Toedieningsvlakke was 10, 5, of lml ensiemkonsentraat/kg strooi. Elke groep se ensiemkonsentraat is verdun met die toepaslike hoeveelheid water om 'n toedieningsvlak van 300ml ensiemoplossing/kg koringstrooi te verkry. 'n Vierde groep is behandel slegs met water teen dieselfde toedieningsvlak, en het gedien as 'n kontrole. Die eksperiment is oor 'n periode van 6 weke uitgevoer. Tydens die proeftydperk is voerinnames, weeklikse gewigstoenames, sowel as voeromsetverhoudings, gedokumenteer. Resultate het betekenisvolle gewigstoenames in die hoe (lOml/kg) en medium (5ml/kg) groepe opgelewer, aangedui deur 'n P-waarde van 0.04. Voeromsetverhoudinge het ook verbeteringe getoon vir bogenoemde twee groepe (P=0.05), terwyl voerinnames nie merkbaar tussen die vier groepe verskil het nie.
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Santos, Luiz Flávio José dos [UNESP]. "Atividade de enzimas digestivas de Lithobates catesbeianus durante o desenvolvimento larval." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/87986.
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santos_lfj_me_jabo.pdf: 849764 bytes, checksum: f44b7996a2cb16332037d11523efd658 (MD5)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Todos os seres vivos necessitam de um suprimento energético, que deve ser obtido de fontes externas. As substâncias simples da dieta dos animas, como a água, os sais minerais e as vitaminas (exceto a vitamina B12), podem ser absorvidas ao longo do trato digestório sem sofrer transformações físicas ou químicas. Entretanto, macromoléculas tais como carboidratos, proteínas e lipídeos, têm de ser convertidas em moléculas pequenas e menos complexas para serem absorvidas. A digestão química dos nutrientes é realizada por hidrólise enzimática, que consiste na cisão de uma ligação química e inserção de uma molécula de água, sendo este processo catalisado pela ação das enzimas digestivas. O objetivo deste estudo foi o de se analisar a variação nas atividades de cinco hidrolases do sistema digestório de rã-touro (Lithobates catesbeianus) durante o desenvolvimento larval, para fornecer subsídios a nutrição animal. Os girinos foram mantidos em aquários, à 27ºC e separados por estádios de desenvolvimento. Amostras de estômago, pâncreas e intestino foram retiradas de 100 animais de cada estádio, congeladas em nitrogênio liquido e armazenadas a -70ºC para posterior homogeneização e determinação da atividade enzimática. A atividade das enzimas tripsina, -amilase e lipase pancreáticas (44,30 U.mg-1, 3,17 U.mg-1, 2,99 U.mg-1 respectivamente), e da maltase intestinal (26,99 U.mg-1), foram detectadas desde o início da fase de alimentação (estádio 26) enquanto que a atividade de catepsina-E gástrica (13,82 U.mg-1), foi estudada a partir do estádio 28, devido a dificuldade de se obter de estômagos antes deste estádio. Durante a pré-metamorfose a catepsina-E não apresentou grande variação em sua atividade, sendo observado aumento ao final do período da prómetamorfose. A atividade das demais...
All living beings require energy supply, wich must be obtained from external sources. Simple substances in the diet of the animals, such as water, minerals and vitamins (except vitamin B12) can be absorbed along the digestive tract without undergoing chemical or physical changes. However, macromolecules such as carbohydrates, proteins and lipids, must be converted into smaller and less complex molecules to be absorbed. The chemical digestion of nutrients is accomplished through enzymatic hydrolysis, which means to break a chemical bond and inserti a water molecule. This process is catalysed by the action of digestive enzymes. The aim of this study was to analyze the activity variation of five hydrolases of the bullfrog’s (Lithobates catesbeianus) digestive system during larval development, to provide subsidies to animal nutrition. The tadpoles were kept in aquaria, at 27 °C and separated by stages of development. Samples of stomach, pancreas and intestine were taken from 100 animals of each stage, frozen in liquid nitrogen and stored at -70ºC for later homogenization and enzyme activity determination. The activity of trypsin, -amylase and pancreatic lipase (44.30 U.mg-1, 3.17 U.mg-1, 2.99 U.mg-1 respectively), and intestinal maltase (26.99 U.mg-1) were detected since the start of feeding (stage 26) while the gastric cathepsin E (13.82 U.mg-1) activity was studied since stage 28, due to difficulty in obtaining stomachs before this stage. During pre-metamorphosis cathepsin-E did not show great variation in its activity, but an increase was observed at the end of the period of prometamorphosis. The other enzymes activity increased significantly in periods that precede metamorphosis, with the highest activities in stage 38 (261.97 U.mg-1 for trypsin, 28.19 U.mg-1 for -amylase and... (Complete abstract click electronic access below)
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Haguet, Quentin. "Étude de bioactivité, de bioconversion et d’absorption par cellules CACO-2 d’un principe actif d’origine végétale pour la prévention du diabète de type 2." Thesis, La Rochelle, 2021. http://www.theses.fr/2021LAROS021.
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Une part grandissante de la population présente des dérèglements de leur métabolisme, regroupés au sein du syndrome métabolique. Ces perturbations engendrent des pathologies comme le diabète de type 2, qui correspond à une déficience de régulation de la glycémie par manque d’efficacité et de production d’insuline. Dans ce contexte, un principe actif végétal à base d’extraits de plantes a été développé. Ce principe nous a permis in vitro et in vivo d’améliorer des paramètres métaboliques liés au diabète de type 2 et à son état préliminaire, le prédiabète. Nous avons effectivement démontré qu’il possède des activités inhibitrices sur les enzymes digestives des sucres et des lipides (α-glucosidase, α-amylase et lipase). L’inhibition la plus forte a été observée sur une α-glucosidase, avec un mécanisme d’inhibition mixte, combiné à une très forte affinité (supérieures à un produit commercial). In vivo, le principe actif a également exprimé les caractéristiques d’un anti-diabétique sur deux modèles de souris. Sur des souris génétiquement diabétiques (db/db), nous avons observé une réduction significative de la glycémie à jeun, des taux d’hémoglobine glyquée et de la prise de masse grasse. Chez des souris black6 (wild type) subissant un régime délétère riche en graisses (high-fat diet), le principe actif a permis de réduire l’élévation de la glycémie à l’issue d’un test de tolérance au maltose et au saccharose. De plus, une étude d’absorption in vitro sur un modèle intestinal (cellules CACO-2) a démontré que certaines molécules de notre principe actif pourraient être absorbées par l’organisme pour agir sur des cibles internes. Lors d’une autre partie du projet, une bioconversion du mélange d’extraits végétaux a été réalisée par de multiples souches de micro-organismes (bactéries lactiques et bactéries et champignons filamenteux). Certains des produits de bioconversion ont été caractérisés et testés sur les mêmes cibles que le principe actif initial mais ce dernier a toujours démontré une bioactivité supérieure ou similaireA growing proportion of the population has metabolic disturbances, grouped under the metabolic syndrome. These disturbances lead to pathologies such as type 2 diabetes, which corresponds to a deficiency in blood sugar regulation due to a lack of efficiency and insulin production. In this context, a mixture of plant extracts was designed. It improved in vitro and in vivo the metabolic parameters related to type 2 diabetes and its preliminary state, pre-diabetes. We have demonstrated that this product has inhibitory activities on sugars and lipids digestive enzymes (α-glucosidase, α-amylase and lipase). The strongest inhibition was observed on an α-glucosidase, with a mixed mechanism of inhibition, combined with a very high affinity (higher than the commercial product). In vivo, the plant extract mix also expressed the characteristics of an anti-diabetic in two mouse models. In genetically diabetic mice (db/db), we observed a significant reduction in fasting blood glucose, glycated haemoglobin levels and body fat gain. In black6 (wild type) mice on a deleterious high-fat diet, the active ingredient reduced the rise in blood glucose levels after an oral tolerance test with maltose or sucrose. In addition, an in vitro absorption study on an intestinal model (CACO-2 cells) indicated that some molecules of the active ingredient could be absorbed by the body to act on internal targets. A set of bioconversions was then performed on our product by multiple strains of microorganisms (lactic acid bacteria and filamentous bacteria and fungi). Some of the bioconversion products have been characterized and tested on the same targets as those tested previously with the plant extract mixture, but the latter has always demonstrated superior or identical bioactivity
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Koroiva, Ricardo. "Enzimas e bactérias lignocelulolíticas do trato digestivo de larvas de Stenochironomus (Diptera:Chironomidae)." Universidade Federal de São Carlos, 2011. https://repositorio.ufscar.br/handle/ufscar/2015.
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Previous issue date: 2011-02-28Financiadora de Estudos e Projetos
The presence of a lignocellulolytic enzyme complex and/or symbiotic microorganisms in the invertebrate guts is an indicative of its ability of using wood as energy source. Despite the microbial involvement in the cellulose digestive processes of some species of aquatic insects, there is a lack of information regarding the importance of microorganisms in the digestive capacity of chironomid larvae. This research focuses on the analysis of the activity of enzymes responsible for cellulose and hemicelluloses digestion and the cultivable bacterial community capable of hydrolyzing wood compounds in the digestive tract of Stenochironomus larvae Kieffer (Diptera, Chironomidae). This is a cosmopolitan genus characterized by mining larvae of submerged decaying branches. Two larval morphotypes were studied. The results of enzymatic analysis in the larval digestive tract, performed by quantification of reducing sugars, showed limited ability of both morphotypes in the degradation of cellulose, but indicated capacity to hydrolyze xylan. There were isolated thirty-one types of colonies during the characterization of bacterial communities, of which nineteen strain responded positively into the ability to hydrolyze at least one of the four substrates used as the main carbon source in the culture media. Degradation capability was assessed using colorimetric tests. The bacteria were classified using 16S rRNA gene analysis. No bacteria capable of degrading lignin were isolated. Pseudomonas was highly richness, Bacillus showed the greatest capacity for degrading different substrates and Sphingobium was present in both Stenochironomus morphotypes. The results obtained in this research emphasize the participation of microorganisms in the degradation of the wood consumed by the Stenochironomus larvae. This is the first report of lignocellulolytic bacteria and lignocellulolytic enzymes in the gut of wood-mining chironomid.
A presença de complexo enzimático lignocelulolítico e/ou de microrganismos no trato digestivo de invertebrados é um indicativo da capacidade desses organismos utilizarem a madeira como fonte de energia. Apesar da participação microbiana em processos digestivos celulósicos em algumas espécies de insetos aquáticos, pouco se sabe sobre a importância dos microrganismos na capacidade digestiva de larvas de quironomídeos. Assim, este estudo teve como objetivo analisar as atividades enzimáticas digestivas de celulose e de hemicelulose e de avaliar a comunidade bacteriana cultivável capaz de hidrolisar compostos de madeira do trato digestivo de larvas de Stenochironomus Kieffer (Diptera, Chironomidae). Este é um gênero cosmopolita caracterizado por larvas minadoras de galhos submersos em decomposição. Foram estudados dois morfotipos larvais. Os resultados da análise enzimática, realizado através da quantificação de açucares redutores, demonstraram limitada capacidade na degradação de celulose, porém indicaram capacidade de hidrólise de xilana. Na caracterização da comunidade bacteriana foram isolados trinta e um tipos de colônias nos dois morfotipos estudados. Dezenove responderam positivamente à capacidade de hidrólise de pelo menos um dos quatro substratos utilizados como principal fonte de carbono nos meios de cultura. A capacidade de degradação foi avaliada através de testes colorimétricos. As bactérias foram identificadas pela análise do gene 16S rRNA. Nenhuma das bactérias isoladas foi capaz de degradar lignina. Pseudomonas foi o gênero com maior riqueza, Bacillus teve a maior capacidade de degradar diferentes substratos e Sphingobium foi encontrado em ambos os morfotipos. Os resultados deste trabalho evidenciam a participação de microrganimos na degradação da madeira consumida pelas larvas de Stenochironomus. Ressalta-se que este é o primeiro registro de bactérias e enzimas lignocelulolíticas no trato digestivo de quironomídeos minadores.