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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Facteurs de variation de la biodisponibilité du zinc, ajouté sous forme organique ou inorganique, chez deux espèces monogastriques en croissance (poulet et porcelet)

Schlegel, Patrick 24 September 2010 (has links) (PDF)
Le zinc est un élément essentiel, un métal polluant et une ressource non renouvelable. Les phytates sont identifiés comme facteur alimentaire principal qui limite la biodisponibilité du Zn chez le monogastrique. Le Zn sous forme organique (DZNO) est supposé moins interagir avec les phytates que celui de forme inorganique (DZNI). La biodisponibilité du Zn alimentaire a été étudiée en fonction des phytates chez le rat, le poulet et le porcelet pour mieux comprendre les mécanismes liés à cette interaction. Les expériences in vivo et les méta-analyses ont permis de mettre en évidence que : 1) L'absorption de DZNO est améliorée par rapport à DZNI, en présence de phytate de sodium qui suggère une protection, de DZNO contre cet antagoniste. 2) La biodisponibilité de DZNO n'est pas améliorée par rapport à DZNI chez le poulet et le porc nourri avec des aliments contenant des phytates d'origine végétale. L'antagonisme des phytates végétales agit sur le Zn natif seulement. 3) L'antagonisme des phytates végétales sur la biodisponibilité du Zn est plus prononcé chez le porc que chez le poulet. Contrairement au porc, le pH gastrique faible chez le poulet serait capable de valoriser le Zn natif, initialement lié aux phytates. 4) Pour une supplémentation optimale du Zn chez le porc, nous suggérons, en plus de la teneur en Zn native, la prise en compte d'une nouvelle variable " P phytique non hydrolysé ". Celle-ci tient compte de l'activité phytasique végétale et microbienne de l'aliment. La supplémentation en Zn peut ainsi être adaptée en fonction du potentiel antagoniste des phytates non hydrolysées. La capacité naturelle du poulet à valoriser le zinc natif limite la marge de progrès.
62

The nutritional value of flaxseed meal for swine

Eastwood, Laura 08 July 2008
The nutritional value of flaxseed meal (FSM), a by-product of the flax crushing industry, has not been evaluated properly for use within swine rations. A series of experiments were conducted to determine the nutritional profile of this novel feed ingredient for pigs.<p>The analysis of FSM revealed that it contains, on a dry matter (DM) basis, 133 g/kg ether extract (EE), 345 g/kg crude protein (CP), 60 g/kg ash, 164 g/kg ADF, 250 g/kg NDF, 102 g/kg crude fibre, 14 g/kg starch and 9 g/kg phosphorus. The gross energy (GE) content of the meal was 5.2 Mcal/kg DM. The ether extract fraction was characterized by, as a percent of total fat, 46.6% á-linolenic acid, an omega-3 fatty acid. Palmitic, stearic, oleic and linoleic acids accounted for 9.5, 4.8, 20.7 and 18.4% of the total fat content respectively. The crude protein content was well balanced for all amino acids with the exception of lysine (4.1% of CP), the level of which falls below that of the requirements for growing pigs (5.3% of CP for pigs 20-50 kg). The apparent digestibility of DM, nitrogen, ash, EE and GE as well as determination of the DE and NE content of FSM was determined for both growing pigs (32 pigs, initial weight 70 ± 3 kg) and gestating sows (26 pigs, parities 2 4). Animals were fed wheat/barley based diets containing 0, 10, 20 or 30% FSM. Faecal grab samples were collected for 3 days after a dietary adaptation period. The apparent digestibility of nutrients in FSM was determined both by regression and by difference calculations. As calculated by difference, the apparent digestibility coefficients for DM, nitrogen, ash, and GE were 63.0, 60.8, 22.3 and 60.5% respectively for growing pigs. The values obtained for sows were 64.1, 58.8, 20.8, 94.9 and 65.4% for DM, nitrogen, ash, EE and GE respectively. The DE content was 3.37 Mcal/kg for growing pigs and 3.52 Mcal/kg for sows. Net energy was then estimated by use of a prediction equation to be 2.34 and 2.44 Mcal/kg for growing pigs and sows. <p>An experiment was conducted to evaluate the growth performances and carcass fatty acid profiles of pigs fed with graded levels of FSM. A total of 200 pigs (100 barrows, 100 gilts; initial weight 32 ± 4 kg) were blocked by gender and housed in groups of 5 pigs per pen. The experiment was divided into three phases for pigs 32-60 kg, 60-85 kg and 85-115 kg. Each group was assigned to one of four dietary treatments containing 0, 5, 10 or 15% FSM at the expense of wheat and soybean meal. At the time of market, 6 pigs per treatment group were randomly selected for carcass fatty acid analysis, and backfat and rib-end loin samples were collected. The average daily gains, average daily feed intakes and gain to feed ratios were not affected by dietary treatment (P > 0.05). Inclusion of 15% dietary FSM increased the ALA content from 11 to 47 (± 0.8) mg/g of backfat (P < 0.001) and from 5 to 10 (± 0.4) mg/g of loin tissue (P < 0.001). Increasing dietary FSM decreased the saturated fatty acid content of backfat (P < 0.01). <p> The final experiment was designed to determine the availability of phosphorus in semi-synthetic diets containing FSM, and to determine the effects of microbial phytase inclusion of this availability. Five treatment groups, 8 barrows (45 ± 4 kg initial weight) each, were fed a diet containing 30% FSM with increasing levels of phytase (0, 575, 1185, 2400 and 2570 FTU/kg). Apparent P digestibility increased from 20.6 to 61.3% with the inclusion of up to 2570 FTU/kg microbial phytase (P < 0.001), and followed a quadratic response pattern with an R2 value of 0.96. A broken-line analysis estimated the optimal phytase inclusion level to be 1415 FTU/kg of diet. Inclusion of just 575 FTU/kg accounted for half of the response, improving the apparent P digestibility by 20% and reducing P excretion by 850 mg/kg dry matter intake.
63

The nutritional value of flaxseed meal for swine

Eastwood, Laura 08 July 2008 (has links)
The nutritional value of flaxseed meal (FSM), a by-product of the flax crushing industry, has not been evaluated properly for use within swine rations. A series of experiments were conducted to determine the nutritional profile of this novel feed ingredient for pigs.<p>The analysis of FSM revealed that it contains, on a dry matter (DM) basis, 133 g/kg ether extract (EE), 345 g/kg crude protein (CP), 60 g/kg ash, 164 g/kg ADF, 250 g/kg NDF, 102 g/kg crude fibre, 14 g/kg starch and 9 g/kg phosphorus. The gross energy (GE) content of the meal was 5.2 Mcal/kg DM. The ether extract fraction was characterized by, as a percent of total fat, 46.6% á-linolenic acid, an omega-3 fatty acid. Palmitic, stearic, oleic and linoleic acids accounted for 9.5, 4.8, 20.7 and 18.4% of the total fat content respectively. The crude protein content was well balanced for all amino acids with the exception of lysine (4.1% of CP), the level of which falls below that of the requirements for growing pigs (5.3% of CP for pigs 20-50 kg). The apparent digestibility of DM, nitrogen, ash, EE and GE as well as determination of the DE and NE content of FSM was determined for both growing pigs (32 pigs, initial weight 70 ± 3 kg) and gestating sows (26 pigs, parities 2 4). Animals were fed wheat/barley based diets containing 0, 10, 20 or 30% FSM. Faecal grab samples were collected for 3 days after a dietary adaptation period. The apparent digestibility of nutrients in FSM was determined both by regression and by difference calculations. As calculated by difference, the apparent digestibility coefficients for DM, nitrogen, ash, and GE were 63.0, 60.8, 22.3 and 60.5% respectively for growing pigs. The values obtained for sows were 64.1, 58.8, 20.8, 94.9 and 65.4% for DM, nitrogen, ash, EE and GE respectively. The DE content was 3.37 Mcal/kg for growing pigs and 3.52 Mcal/kg for sows. Net energy was then estimated by use of a prediction equation to be 2.34 and 2.44 Mcal/kg for growing pigs and sows. <p>An experiment was conducted to evaluate the growth performances and carcass fatty acid profiles of pigs fed with graded levels of FSM. A total of 200 pigs (100 barrows, 100 gilts; initial weight 32 ± 4 kg) were blocked by gender and housed in groups of 5 pigs per pen. The experiment was divided into three phases for pigs 32-60 kg, 60-85 kg and 85-115 kg. Each group was assigned to one of four dietary treatments containing 0, 5, 10 or 15% FSM at the expense of wheat and soybean meal. At the time of market, 6 pigs per treatment group were randomly selected for carcass fatty acid analysis, and backfat and rib-end loin samples were collected. The average daily gains, average daily feed intakes and gain to feed ratios were not affected by dietary treatment (P > 0.05). Inclusion of 15% dietary FSM increased the ALA content from 11 to 47 (± 0.8) mg/g of backfat (P < 0.001) and from 5 to 10 (± 0.4) mg/g of loin tissue (P < 0.001). Increasing dietary FSM decreased the saturated fatty acid content of backfat (P < 0.01). <p> The final experiment was designed to determine the availability of phosphorus in semi-synthetic diets containing FSM, and to determine the effects of microbial phytase inclusion of this availability. Five treatment groups, 8 barrows (45 ± 4 kg initial weight) each, were fed a diet containing 30% FSM with increasing levels of phytase (0, 575, 1185, 2400 and 2570 FTU/kg). Apparent P digestibility increased from 20.6 to 61.3% with the inclusion of up to 2570 FTU/kg microbial phytase (P < 0.001), and followed a quadratic response pattern with an R2 value of 0.96. A broken-line analysis estimated the optimal phytase inclusion level to be 1415 FTU/kg of diet. Inclusion of just 575 FTU/kg accounted for half of the response, improving the apparent P digestibility by 20% and reducing P excretion by 850 mg/kg dry matter intake.
64

Deposição mineral óssea em frangos de corte suplementados com fitase de Citrobracter braakii / Bone mineral accretion in broilers supplemented with phytase Citrobracter braakii

Anschau, Daniel Luis January 2013 (has links)
O fitato é um fator antinutricional conhecido que indisponibiliza a maior parte do fósforo (P). Fitases exógenas hidrolisam o fitato ofertando parcialmente o P desta molécula. Este trabalho teve por objetivo investigar a suplementação alimentar de uma fitase expressa pela bactéria Citrobracter braakii com diferentes níveis de Ca e P sobre o desempenho zootécnico, características esqueléticas e digestibilidade de Ca e P para frangos de corte. Foram utilizados 350 frangos machos, Cobb 500, distribuídos em um delineamento experimental inteiramente casualizado em gaiolas composto por 7 tratamentos com 10 repetições de 5 aves cada. Uma dieta controle com 0,42 % de P disponível (Pd) e 0,84 % de Ca, e com reduções graduais de 0,32 %, 0,26 %, 0,20 %, 0,14 % de Pd e 0,80 % de Ca foram formuladas. A adição de fitase foi de (500 e 1.000 FTU / kg, respectivamente), em dietas de níveis deficientes de Pd. Coletas de tíbia, fêmur, e dedo médio direito, bem como do conteúdo ileal foram realizadas. As inclusões de fitase resultaram em melhoria no desempenho zootécnico, sendo que a adição no nível de 1000 FTU foi superior para todas as respostas medidas. Valores de equivalência para adição da fitase foram estimados por equação de regressão com níveis de Pd respectivamente de 0,094 % para (ganho de peso - GP), 0,137 % para (conversão alimentar - CA), 0,098 % (cinza da tíbia), 0,104 % (cinza do fêmur), 0,083 % (cinza do dedo médio), respostas para Ca de 0,094 %; 0,145 %; 0,084 % para (tíbia, fêmur e dedo médio) e respostas de P de 0,102 %; 0,111 %; 0,077 % para (tíbia, fêmur e dedo médio) para 500 FTU/Kg, e de 0,143 % (GP), 0,156 % (CA), 0,168 % (cinza da tíbia), 0,160 % (cinza do fêmur), 0,165 % (cinza do dedo médio), respostas para Ca de 0,172 %; 0,163 %; 0,195 % para (tíbia, fêmur e dedo médio) e respostas para P de 0,173 %; 0,157 %; 0,158 % para (tíbia, fêmur e dedo médio) para 1000 FTU/Kg. / The anti-nutritional factor phytate is known that most indisponibiliza phosphorus (P). Exogenous phytase hydrolyzes the phytate P offering part of this molecule. This study aimed to investigate the dietary supplementation of a phytase expressed by bacteria Citrobracter braakii with different levels of Ca and P on the performance, features and skeletal digestibility of Ca and P for broilers. We used 350 male chickens, Cobb 500, distributed in a completely randomized design in cages composed of seven treatments with 10 replicates of 5 chicks each. A control diet with 0.42% available P (Pd) and 0.84% Ca, and gradual reductions of 0.32%, 0.26%, 0.20%, 0.14% and Pd 0 80% Ca were formulated. The addition of phytase of (500 to 1000 FTU / kg, respectively) in diets deficient levels of Pd. Collections of the tibia, femur, and right middle finger, and the ileal content were performed. The inclusions phytase resulted in improvement in the performance, with the addition of 1000 FTU level was higher for all responses measured. Equivalency values for phytase addition were estimated by regression equation with phosphorus levels respectively to 0.094% (weight gain - GP) to 0.137% (feed - CA), 0.098% (gray tibia), 0.104% (gray femur), 0.083% (gray middle finger), responses to Ca 0.094%, 0.145%, 0.084% for (tibia, femur and middle finger) and answers P 0.102%, 0.111%, 0.077% for (tibia, femur and middle finger) to 500 FTU / kg, and 0.143% (GP), 0.156% (CA), 0.168% (gray tibia), 0.160% (gray femur), 0.165% (gray finger average), responses to Ca 0.172%, 0.163%, 0.195% for (tibia, femur and middle finger) and responses to P of 0.173%, 0.157%, 0.158% for (tibia, femur and middle finger) to 1000 FTU / Kg.
65

Deposição mineral óssea em frangos de corte suplementados com fitase de Citrobracter braakii / Bone mineral accretion in broilers supplemented with phytase Citrobracter braakii

Anschau, Daniel Luis January 2013 (has links)
O fitato é um fator antinutricional conhecido que indisponibiliza a maior parte do fósforo (P). Fitases exógenas hidrolisam o fitato ofertando parcialmente o P desta molécula. Este trabalho teve por objetivo investigar a suplementação alimentar de uma fitase expressa pela bactéria Citrobracter braakii com diferentes níveis de Ca e P sobre o desempenho zootécnico, características esqueléticas e digestibilidade de Ca e P para frangos de corte. Foram utilizados 350 frangos machos, Cobb 500, distribuídos em um delineamento experimental inteiramente casualizado em gaiolas composto por 7 tratamentos com 10 repetições de 5 aves cada. Uma dieta controle com 0,42 % de P disponível (Pd) e 0,84 % de Ca, e com reduções graduais de 0,32 %, 0,26 %, 0,20 %, 0,14 % de Pd e 0,80 % de Ca foram formuladas. A adição de fitase foi de (500 e 1.000 FTU / kg, respectivamente), em dietas de níveis deficientes de Pd. Coletas de tíbia, fêmur, e dedo médio direito, bem como do conteúdo ileal foram realizadas. As inclusões de fitase resultaram em melhoria no desempenho zootécnico, sendo que a adição no nível de 1000 FTU foi superior para todas as respostas medidas. Valores de equivalência para adição da fitase foram estimados por equação de regressão com níveis de Pd respectivamente de 0,094 % para (ganho de peso - GP), 0,137 % para (conversão alimentar - CA), 0,098 % (cinza da tíbia), 0,104 % (cinza do fêmur), 0,083 % (cinza do dedo médio), respostas para Ca de 0,094 %; 0,145 %; 0,084 % para (tíbia, fêmur e dedo médio) e respostas de P de 0,102 %; 0,111 %; 0,077 % para (tíbia, fêmur e dedo médio) para 500 FTU/Kg, e de 0,143 % (GP), 0,156 % (CA), 0,168 % (cinza da tíbia), 0,160 % (cinza do fêmur), 0,165 % (cinza do dedo médio), respostas para Ca de 0,172 %; 0,163 %; 0,195 % para (tíbia, fêmur e dedo médio) e respostas para P de 0,173 %; 0,157 %; 0,158 % para (tíbia, fêmur e dedo médio) para 1000 FTU/Kg. / The anti-nutritional factor phytate is known that most indisponibiliza phosphorus (P). Exogenous phytase hydrolyzes the phytate P offering part of this molecule. This study aimed to investigate the dietary supplementation of a phytase expressed by bacteria Citrobracter braakii with different levels of Ca and P on the performance, features and skeletal digestibility of Ca and P for broilers. We used 350 male chickens, Cobb 500, distributed in a completely randomized design in cages composed of seven treatments with 10 replicates of 5 chicks each. A control diet with 0.42% available P (Pd) and 0.84% Ca, and gradual reductions of 0.32%, 0.26%, 0.20%, 0.14% and Pd 0 80% Ca were formulated. The addition of phytase of (500 to 1000 FTU / kg, respectively) in diets deficient levels of Pd. Collections of the tibia, femur, and right middle finger, and the ileal content were performed. The inclusions phytase resulted in improvement in the performance, with the addition of 1000 FTU level was higher for all responses measured. Equivalency values for phytase addition were estimated by regression equation with phosphorus levels respectively to 0.094% (weight gain - GP) to 0.137% (feed - CA), 0.098% (gray tibia), 0.104% (gray femur), 0.083% (gray middle finger), responses to Ca 0.094%, 0.145%, 0.084% for (tibia, femur and middle finger) and answers P 0.102%, 0.111%, 0.077% for (tibia, femur and middle finger) to 500 FTU / kg, and 0.143% (GP), 0.156% (CA), 0.168% (gray tibia), 0.160% (gray femur), 0.165% (gray finger average), responses to Ca 0.172%, 0.163%, 0.195% for (tibia, femur and middle finger) and responses to P of 0.173%, 0.157%, 0.158% for (tibia, femur and middle finger) to 1000 FTU / Kg.
66

Fitase e fontes minerais para frangos de corte / Phytase and mineral sources to broiler chickens

Serafini, Natália Chaves January 2018 (has links)
Um estudo foi realizado para avaliar os efeitos da suplementação de uma fitase e duas fontes de Zinco (Zn), Cobre (Cu) e Manganês (Mn) sobre o desempenho produtivo e a digestibilidade de nutrientes em frangos de corte. Um total de 528 pintos da linhagem Cobb 500, machos com um dia (d) de idade foram distribuídos em 4 tratamentos com 12 repetições de 11 aves cada. Um arranjo fatorial 2 x 2 foi utilizado, sendo duas suplementações de fitase (com ou sem) e duas fontes minerais (inorgânica ou orgânica). A suplementação de fitase foi de 500 unidades de fitase (FTU)/kg, enquanto Zn-Cu-Mn foram suplementados em concentrações de 32-30-32 ou 100-120-100 ppm para as formas orgânica e inorgânica, respectivamente. Foi utilizado um programa alimentar de duas fases: inicial (1 a 12 d) e crescimento (12 a 25 d). As dietas foram formuladas de forma a atender as exigências nutricionais dos animais de acordo com a idade, exceto para Fósforo (P) disponível (Pd) e Cálcio (Ca), que tiveram níveis reduzidos (0,32% e 0,77 % na dieta inicial e 0,23% e 0,71 % na dieta crescimento para Pd e Ca, respectivamente). Os níveis de metionina nas dietas foram reduzidos conforme a adição de minerais orgânicos, que tinham como agente quelante metionina hidróxi-análoga (HMTBA). As tíbias das aves foram coletadas aos 12 e aos 25 dias de idade para determinação do teor de cinzas, Ca e P Aos 25 dias, também, foi coletado conteúdo ileal para determinação da digestibilidade ileal aparente da matéria seca (MS), Ca e P. A suplementação de fitase aumentou o ganho de peso (GP) e a conversão alimentar (CA) dos frangos dos 12 aos 25 dias e também no período acumulado (1 a 25 d). Foi observada interação entre fontes minerais e as fitases para digestibilidade de MS e P (P<0,05). A digestibilidade ileal da matéria seca foi maior nos frangos alimentados com dietas suplementadas com fitase, e também naqueles que receberam fontes inorgânicas de Zn-Cu-Mn. Os frangos que receberam dietas com fitase tiveram melhores coeficientes de digestibilidade de Ca e P (P<0,05). A fonte orgânica de microminerais resultou em maior o conteúdo de tíbia em percentual aos 12 dias. A suplementação de 500 FTU/kg de fitase nas dietas à base de milho e soja também levou a um aumento no conteúdo de cinzas das tíbias aos 12 e 25 dias, mas não houveram diferenças entre o conteúdo de Ca e P entre os animais alimentados com e sem fitase. Conclui-se que a suplementação de fitase melhora o desempenho produtivo, digestibilidade ileal de Ca e P e a mineralização óssea, e que concentrações mais baixas de minerais, através do uso de fontes orgânicas, podem ser utilizadas sem prejuízos ao desempenho animal. / A study was conducted to evaluate the effects of dietary supplementation of phytase and mineral sources of zinc (Zn), copper (Cu) and manganese (Mn) on growth performance and nutrient digestibility of broiler chickens. A total of 528 Cobb x Cobb 500 male chicks were distributed into 4 treatments with 12 replicates of 11 birds each. A 2 x 2 factorial arrangement was used with two enzyme supplementation (with or without) and two mineral sources (inorganic or organic). Phytase supplementation were 500 phytase units (FTU)/kg whereas Zn-Cu-Mn were supplemented in a concentration of 32-30-32 or 100-120-100 ppm in organic and inorganic forms, respectively. A two-phase feeding program was used, from 1 to 12 (starter) and from 12 to 25 d (grower). Diets were formulated to meet bird’s nutritional requirements according to age, except for Available Phosphorus (Av.P) and Calcium (Ca), that were formulated at 0,32% and 0,77% in starter and 0,23% and 0,71% in grower, to Av P and Ca, respectively. Methionine levels were reduced according to organic minerals supplementation, that had hydroxy-analogue methionine (HMTBA) as the chelating agent. Tibiae were collected at 12 and 25 d to measure ash, Ca and P content Also, at 25 d, ileal contents were collected to determine apparent ileal digestibility of dry matter (DM), Ca and P. Body weight gain (BWG) and feed conversion ratio (FCR) was higher with phytase supplementation from 12 to 25 d and 1 to 25 d. Dry matter (DM) digestibility was higher in animals fed diets with phytase and also in those receiving inorganic minerals. Ca and P digestibility were improved by phytase. Interactions between mineral sources and enzyme were observed to DM and P digestibility. Treatment consisting of inorganic minerals and phytase was associated with higher values of P and DM digestibility. Organic mineral source improved ash content in percentage at 12 d. Supplementing phytase to the diets led to an increase in the percentage of ash content at 12 and 25 d, but there were no statistical differences in Ca and P content between animals receiving diets with or without the enzyme. In conclusion, phytase has benefitial impacts on performance, digestibility and bone mineralisation, and lower concentrations of minerals, with organic source, can be supplied without losses to animal performance.
67

Produção de fitase por fungos endofíticos dos manguezais do Estado de São Paulo

Silveira, Lucas de Abreu 27 June 2017 (has links)
Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2017-10-03T11:55:00Z No. of bitstreams: 1 DissLAS.pdf: 1333707 bytes, checksum: 130c53c4b36b129960094efeec36e4c7 (MD5) / Approved for entry into archive by Ronildo Prado (bco.producao.intelectual@gmail.com) on 2018-01-29T17:16:17Z (GMT) No. of bitstreams: 1 DissLAS.pdf: 1333707 bytes, checksum: 130c53c4b36b129960094efeec36e4c7 (MD5) / Approved for entry into archive by Ronildo Prado (bco.producao.intelectual@gmail.com) on 2018-01-29T17:16:26Z (GMT) No. of bitstreams: 1 DissLAS.pdf: 1333707 bytes, checksum: 130c53c4b36b129960094efeec36e4c7 (MD5) / Made available in DSpace on 2018-01-29T17:20:51Z (GMT). No. of bitstreams: 1 DissLAS.pdf: 1333707 bytes, checksum: 130c53c4b36b129960094efeec36e4c7 (MD5) Previous issue date: 2017-06-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A source of great biotechnological potential for the production of enzymes are endophytic microorganisms. These microorganisms are capable of producing a wide variety of enzymes, among them phytase, which is responsible for phytate hydrolysis. The objective of this work was to evaluate the potential of endophytic fungi of the mangroves of the state of São Paulo for phytase production. Initially, a qualitative selection of 33 isolates with PSM (Phytase Screening Medium) and a second quantitative selection was carried out, in which the preselected fungi were submitted to solid state fermentation (SSF) for phytase production. Among the isolates evaluated, the fungus Aspergillus awamori 9(4) was selected, which presented phytase activity of 43.98 U/100g when submitted to SSF culture for 72 h with soybean meal as substrate. In order to improve phytase production, the use of wheat bran as substrate was evaluated, reaching an activity of 82.77 U/100g, under the same conditions of cultivation. The use of KH2PO4 as an inducer in phytase production and the use of dialysis for the removal of interfering ions from the crude extract in phytase activity were also evaluated. For the experiments performed without the inducer, the dialysis of the extract resulted in activities of 85.42 U/100g with soybean meal and 55.44 U/100g with wheat bran. For the experiments of cultivation with the inductor and then dialysed resulted in activities of 132.35 U/100g with soybean meal and 115.52 U/100g with wheat bran, indicating that the effect of the inducer is positive in the production of Phytase and that dialysis is important for enzyme activity. These results indicate that the endophytic fungus of the mangrove of the State of São Paulo is promising for the production of phytase enzyme, being unpublished the use of endophytic micro-organisms for the production of this enzyme. / Uma fonte de grande potencial biotecnológico para a produção de enzimas são os microrganismos endofíticos. Estes microrganismos são capazes de produzir grande variedade de enzimas, dentre elas a fitase, que é responsável pela hidrólise do fitato. O objetivo deste trabalho foi avaliar o potencial de fungos endofíticos dos manguezais do estado de São Paulo para a produção de fitase. Inicialmente foi realizada uma seleção qualitativa de 33 isolados com meio diferencial PSM (Phytase Screening Medium), e uma segunda seleção quantitativa, em que os fungos pré-selecionados foram submetidos à fermentação em estado sólido (FES) para produção de fitase. Dentre os isolados avaliados, selecionou-se o fungo Aspergillus awamori 9(4), tendo este apresentado atividade de fitase de 43,98 U/100g quando submetido a cultivo FES por 72 h com farelo de soja como substrato. A fim de melhorar a produção de fitase, avaliou-se o uso de farelo de trigo como substrato, atingindo assim atividade de 82,77 U/100g, sob as mesmas condições de cultivo. Avaliou-se também o uso de KH2PO4 como indutor na produção de fitase e o uso de diálise para a remoção de íons interferentes do extrato bruto na atividade de fitase. Para os experimentos realizados sem o indutor, a diálise do extrato resultou em atividades de 85,42 U/100g com farelo de soja e 55,44 U/100g com farelo de trigo. Já para os experimentos de cultivo com o indutor e em seguida dialisados resultaram em atividades de 132,35 U/100g com farelo de soja e 115,52 U/100g com farelo de trigo, indicando que o efeito do indutor é positivo na produção de fitases e que a diálise é importante para a atividade enzimática. Esses resultados indicam que o fungo endofítico do manguezal do Estado de São Paulo é promissor para a produção da enzima fitase, sendo inédito o uso de micro-organismos endofíticos para a produção desta enzima.
68

Efeito da suplementação de enzimas sobre o processamento e digestibilidade de dietas extrusadas para cães contendo farelo de trigo /

Sá, Fabiano Cesar. January 2011 (has links)
Orientador: Aulus Cavalieri Carciofi / Banca: João Martins Pizauro Junior / Banca: José Roberto Sartori / Resumo: O farelo de trigo é um coproduto da indústria alimentícia com custo acessível e importante fonte de fibra e amido que vem sendo empregado para cães. Contudo, este ingrediente apresenta Polissacarídeos Não Amiláceos (PNA's), que não são digeridos pelos cães e podem causar distúrbios gastrintestinais, que interferem na absorção dos nutrientes. Com o intuito de aumentar a biodisponibilidade dos nutrientes do farelo de trigo em dietas extrusadas para cães, avaliou-se a suplementação com uma mistura de enzimas sobre o coeficiente de digestibilidade dos nutrientes, qualidade e produção de fezes e parâmetros fermentativos intestinais. Foram formuladas duas dietas experimentais isonutritivas. A primeira possuía apenas milho e quirera de arroz como fonte de amido e fibra de cana de açúcar como fonte de fibra, que foi denominada ração controle negativo (CN). A segunda formulação apresentava 25% de farelo de trigo e foi desdobrada em quatro tratamentos: CP - dieta controle positivo, com farelo de trigo e sem adição de enzimas; ENZ1 - com enzimas na mistura antes da extrusão; ENZ2 - com as enzimas do ENZ1 mais α-amilase, na mistura antes da extrusão; ENZ2Pex - com as enzimas do ENZ2 após extrusão, como cobertura. O experimento seguiu delineamento em blocos casualizados no tempo, com dois blocos de 15 animais, três animais por tratamento em cada bloco e seis cães por tratamento. Os dados obtidos foram submetidos à análise de variância e as médias dos cinco tratamentos comparadas pelo teste de Tukey a 5% de probabilidade. Os resultados foram, também, avaliados por meio de contrastes ortogonais pré-estabelecidos, a 5% de probabilidade. A adição de farelo de trigo levou à redução da digestibilidade dos nutrientes (p<0,05). A mistura de enzimas não resultou em diferenças na digestibilidade, qualidade das fezes e produtos de fermentação microbiana fecal ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The wheat bran is a byproduct of the food industry with affordable and important source of fiber and starch that has been used for dogs. However, this ingredient has no-starch polysaccharides (NSP), which are not digested by dogs and can cause gastrointestinal disturbances, which interfere with absorption of nutrients. In order to increase the bioavailability of nutrients in wheat bran extruded diets for dogs, we assessed whether supplementation with a mixture of enzymes on the digestibility of nutrients, quality and production of feces and intestinal fermentation parameters. Two experimental diets were formulated isonutrients. The first had only corn and broken rice as a source of starch and sugar cane fiber as a fiber source, which was designated negative control diet (NC). The second formulation showed a 25% wheat bran and was split into four treatments: CP - positive control diet with wheat bran and without enzymes; ENZ1 - with enzymes in the mixture before extrusion; ENZ2 - with enzymes ENZ1 more α-amylase in the mixture before extrusion; ENZ2Pex - with enzymes ENZ2 after extrusion, as cover. The experiment followed a randomized block design in time, with two blocks of 15 animals, three animals per treatment in each block and six dogs per treatment. The data were subjected to analysis of variance and the mean of five treatment groups were compared by Tukey test at 5% probability. The results were also evaluated using orthogonal contrasts pre-set at 5% probability. The addition of wheat bran led to reduced digestibility of nutrients (p <0.05). The mixture of enzymes resulted in no differences in digestibility, stool quality and fecal microbial fermentation products (p> 0.05). The productivity of feed increased with the addition of the mixture of enzymes ENZ2, reducing the cost of eletctricity production in the diet / Mestre
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Fitase e fontes minerais para frangos de corte / Phytase and mineral sources to broiler chickens

Serafini, Natália Chaves January 2018 (has links)
Um estudo foi realizado para avaliar os efeitos da suplementação de uma fitase e duas fontes de Zinco (Zn), Cobre (Cu) e Manganês (Mn) sobre o desempenho produtivo e a digestibilidade de nutrientes em frangos de corte. Um total de 528 pintos da linhagem Cobb 500, machos com um dia (d) de idade foram distribuídos em 4 tratamentos com 12 repetições de 11 aves cada. Um arranjo fatorial 2 x 2 foi utilizado, sendo duas suplementações de fitase (com ou sem) e duas fontes minerais (inorgânica ou orgânica). A suplementação de fitase foi de 500 unidades de fitase (FTU)/kg, enquanto Zn-Cu-Mn foram suplementados em concentrações de 32-30-32 ou 100-120-100 ppm para as formas orgânica e inorgânica, respectivamente. Foi utilizado um programa alimentar de duas fases: inicial (1 a 12 d) e crescimento (12 a 25 d). As dietas foram formuladas de forma a atender as exigências nutricionais dos animais de acordo com a idade, exceto para Fósforo (P) disponível (Pd) e Cálcio (Ca), que tiveram níveis reduzidos (0,32% e 0,77 % na dieta inicial e 0,23% e 0,71 % na dieta crescimento para Pd e Ca, respectivamente). Os níveis de metionina nas dietas foram reduzidos conforme a adição de minerais orgânicos, que tinham como agente quelante metionina hidróxi-análoga (HMTBA). As tíbias das aves foram coletadas aos 12 e aos 25 dias de idade para determinação do teor de cinzas, Ca e P Aos 25 dias, também, foi coletado conteúdo ileal para determinação da digestibilidade ileal aparente da matéria seca (MS), Ca e P. A suplementação de fitase aumentou o ganho de peso (GP) e a conversão alimentar (CA) dos frangos dos 12 aos 25 dias e também no período acumulado (1 a 25 d). Foi observada interação entre fontes minerais e as fitases para digestibilidade de MS e P (P<0,05). A digestibilidade ileal da matéria seca foi maior nos frangos alimentados com dietas suplementadas com fitase, e também naqueles que receberam fontes inorgânicas de Zn-Cu-Mn. Os frangos que receberam dietas com fitase tiveram melhores coeficientes de digestibilidade de Ca e P (P<0,05). A fonte orgânica de microminerais resultou em maior o conteúdo de tíbia em percentual aos 12 dias. A suplementação de 500 FTU/kg de fitase nas dietas à base de milho e soja também levou a um aumento no conteúdo de cinzas das tíbias aos 12 e 25 dias, mas não houveram diferenças entre o conteúdo de Ca e P entre os animais alimentados com e sem fitase. Conclui-se que a suplementação de fitase melhora o desempenho produtivo, digestibilidade ileal de Ca e P e a mineralização óssea, e que concentrações mais baixas de minerais, através do uso de fontes orgânicas, podem ser utilizadas sem prejuízos ao desempenho animal. / A study was conducted to evaluate the effects of dietary supplementation of phytase and mineral sources of zinc (Zn), copper (Cu) and manganese (Mn) on growth performance and nutrient digestibility of broiler chickens. A total of 528 Cobb x Cobb 500 male chicks were distributed into 4 treatments with 12 replicates of 11 birds each. A 2 x 2 factorial arrangement was used with two enzyme supplementation (with or without) and two mineral sources (inorganic or organic). Phytase supplementation were 500 phytase units (FTU)/kg whereas Zn-Cu-Mn were supplemented in a concentration of 32-30-32 or 100-120-100 ppm in organic and inorganic forms, respectively. A two-phase feeding program was used, from 1 to 12 (starter) and from 12 to 25 d (grower). Diets were formulated to meet bird’s nutritional requirements according to age, except for Available Phosphorus (Av.P) and Calcium (Ca), that were formulated at 0,32% and 0,77% in starter and 0,23% and 0,71% in grower, to Av P and Ca, respectively. Methionine levels were reduced according to organic minerals supplementation, that had hydroxy-analogue methionine (HMTBA) as the chelating agent. Tibiae were collected at 12 and 25 d to measure ash, Ca and P content Also, at 25 d, ileal contents were collected to determine apparent ileal digestibility of dry matter (DM), Ca and P. Body weight gain (BWG) and feed conversion ratio (FCR) was higher with phytase supplementation from 12 to 25 d and 1 to 25 d. Dry matter (DM) digestibility was higher in animals fed diets with phytase and also in those receiving inorganic minerals. Ca and P digestibility were improved by phytase. Interactions between mineral sources and enzyme were observed to DM and P digestibility. Treatment consisting of inorganic minerals and phytase was associated with higher values of P and DM digestibility. Organic mineral source improved ash content in percentage at 12 d. Supplementing phytase to the diets led to an increase in the percentage of ash content at 12 and 25 d, but there were no statistical differences in Ca and P content between animals receiving diets with or without the enzyme. In conclusion, phytase has benefitial impacts on performance, digestibility and bone mineralisation, and lower concentrations of minerals, with organic source, can be supplied without losses to animal performance.
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Filmes de polipirrol como matrizes para a imobilização das enzimas fitase e polifenol oxidase e aplicados como biossensores / Polypyrrole films as matrices for the immobilization of phytase and polyphenol oxidase enzymes and applied as biosensors

Valquiria da Cruz Rodrigues Barioto 17 March 2014 (has links)
Este trabalho teve como objetivo o desenvolvimento de biossensores eletroquímicos baseados na imobilização de duas enzimas diferentes em filmes de polipirrol (PPI) eletrodepositados, a fitase e a polifenol oxidase (PFO), esta última na forma de extrato bruto do fruto de abacate. Como a fitase hidrolisa cataliticamente ácido fítico (AF) em íons fosfatos, foram preparados biossensores por imobilização da enzima sobre filmes de PPI para a detecção indireta de ácido fítico via íons fosfatos. Foram utilizados dois métodos de imobilização; no primeiro, a enzima, fitase, foi imobilizada ao filme de PPI por imersão do filme em uma solução contendo a enzima por um período de 2 h, no segundo, a fitase foi encapsulada em lipossomos de dipalmitoil fosfatidil glicerol (DPPG) e depois foi imobilizada nos filmes de PPI depositados em eletrodos impressos. O segundo método se mostrou melhor para a detecção de ácido fítico, pois levou a um maior alcance linear e um baixo valor de limite de detecção. Neste caso, verificou-se que o DPPG preservou a integridade enzimática e levou a biossensores mais estáveis e sensíveis. Já para a PFO, que catalisa a oxidação de compostos fenólicos a quinonas, foram preparados biossensores para a detecção indireta de catecol. Para esta enzima, foram utilizados três métodos de imobilização: adsorção, ligação cruzada e confinamento, sendo o último que levou a melhores respostas. O método de confinamento consiste na adição da enzima, juntamente com o monômero, à solução de eletropolimerização, quando se procede com a metodologia normal de preparo dos filmes de PPI, que foram caracterizados por: microscopia de força atômica (AFM), microscopia eletrônica de varredura (MEV), espectroscopia de infravermelho por transformada de Fourier (FTIR) e espectroscopia de reflexão e absorção no infravermelho com modulação da polarização (PM-IRRAS). Estas técnicas de caracterização permitiram com que a presença da enzima fosse associada às modificações das características estruturais e morfológicas dos filmes de PPI. / This doctoral thesis reports on the development of electrochemical biosensors based on the immobilization of enzymes phytase and polyphenol oxidase (PPO) (the latter in the form of crude extract of avocado fruit) on electrodeposited polypyrrole films (PPY). As phytase catalytically hydrolyzes phytic acid (PA) in phosphate ions, biosensors were prepared by its immobilization on PPY films for the indirect detection of PA via phosphate ions. In the first method the enzyme was maintained on the PPY film for a period of 2 h, whereas in the second, it was encapsulated in Dipalmitoyl Phosphatidyl glycerol (DPPG) and immobilized on printed electrodes. The second system proved more viable for the detection of PA and showed broader linear range and low detection limit because DPPG preserved the integrity of the enzyme and produced more stable and sensitive biosensors. Regarding PPO, which catalyzes the oxidation of phenolic compounds to quinones, biosensors for the indirect detection of catechol via the formation of quinone in solution were prepared. Three methods of immobilization were used: adsorption, cross-linking and confinement. The latter yielded favorable results in comparison to other methods. The films were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM) spectroscopy, fourier transform infrared (FTIR) spectroscopy and reflection absorption and infrared polarization modulation (PM-IRRAS) techniques and revealed the presence of the enzyme and a modification in the structural characteristics and morphology of the films.

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