Les co-produits agricoles, son et paille de blé, sont riches en arabinoxylanes (AX) qui après hydrolyse peuvent fournir des molécules pour des usages variés: xylo-oligosides (prébiotiques), xylose (xylitol), acide férulique (vanilline, antioxydant). L’étude a visé à mettre en place un procédé intégré et éco-compatible, depuis l'hydrolyse enzymatique des AX du son de blé jusqu'à la purification de l'acide férulique. Des cocktails hémicellulasiques produits par culture de la bactérie Thermobacillus xylanilyticus sur paille ou son de blé et mis en œuvre dans des conditions variées ont permis de libérer des glucides (mono- et oligomères) et de l’acide férulique. Afin d’augmenter la monomérisation, deux nouvelles β-xylosidases ont été produites à partir de T. xylanilyticus et caractérisées. Elles ont été testées pour complémenter des cocktails hémicellulasiques complexes issus de T. xylanilyticus et étudiées en mélange avec une xylanase et une arabinosidase pures. Le choix d’une résine anionique faible sous forme base libre pour séparer les fractions glucidique et phénolique et purifier l’acide férulique s’est également inscrit dans une démarche d’éco-conception : la résine Amberlyst A21 a montré une bonne affinité pour l’acide férulique et sa régénération a libéré une fraction très concentrée. La déminéralisation préalable de l’hydrolysat par électrodialyse a permis d’accroître la capacité de la résine pour l’acide et la pureté de la fraction récupérée, potentiellement cristallisable. / Agriculture by-products (wheat bran and straw) are rich in arabinoxylans (AX). These polymers composed of a main chain of β-(1,4) linked xylose ramified by arabinose and ferulic acid, are sources of molecules for various applications: xylooligosaccharides as prebiotics, xylose to synthesize xylitol, a non-cariogenic sweetener, or ferulic acid as a precursor of vanillin or an antioxidant molecule for packaging applications. The aim of this work was to set up an eco-friendly process ranging from wheat bran AX hydrolysis to ferulic acid purification.Hemicellulasic cocktails obtained by growing Thermobacillus xylanilyticus on wheat straw or wheat bran were implemented in various conditions. They released a carbohydrate fraction (mono- and oligosaccharides) and ferulic acid. In order to increase the monomerization, two new β-xylosidases were grown from T. xylanilyticus and characterized. They were tested to supplement the complex hemicellulasic cocktails from T. xylanilyticus and studied in mixture with a pure xylanase and a pure arabinosidase.The choice of a weak anionic resin under free base form to separate the glucidic and the phenolic fractions and to purify ferulic acid was also driven by environnement purposes: Amberlyst A21 resin showed a good affinity for ferulic acid and regeneration allowed a concentrated fraction of ferulate to be obtained. Prior demineralization by electrodialysis increased the capacity of the resin for ferulic acid and the purity of the recovered fraction, potentially allowing crystallization.

La biomasse lignocellulosique est au cœur du développement de la bioraffinerie de par l’intérêt de fractionner ses composants avec divers procédés pour la production de biocarburants, de molécules d’intérêt et de matériaux agro-sourcés. L’objectif de cette thèse visait à étudier la transformation des xylanes du son de blé en molécules tensio-actives (esters de pentoses). Cette transformation a été envisagée en deux étapes : une première étape d’hydrolyse du son de blé par des hémicellulases pour la production de xylose et d’arabinose, suivie d’une seconde étape d’acylation de ces glucides par une lipase pour accéder aux esters de pentoses. La thèse s’est principalement focalisée sur l’étude de la transestérification de D- xylose et de L-arabinose (purs ou issus d’un hydrolysat de son de blé) et du laurate de vinyle par la lipase immobilisée N435. L’influence de divers paramètres réactionnels a été étudiée. Des mono- et diesters lauriques de D-xylose et de L-arabinose, dont la structure a été caractérisée, sont produits par la lipase. Les propriétés physico-chimiques de ces esters lauriques de pentoses, originaux et nouvellement décrits, ont été évaluées et ont montré l’intérêt de ces molécules en tant que tensio-actifs. Une approche préliminaire a également été développée pour étudier la synthèse d’esters lauriques de xylo-oligosaccharides par la lipase N435. Nos résultats montrent que cette production a lieu mais qu’elle est moins efficace que dans le cas des monosaccharides. La transestérification catalysée par la lipase N435 reste dans ce cas à optimiser, de même que la purification et la caractérisation de ces esters lauriques de xylo-oligosaccharides. / Lignocellulosic biomass is at the center of biorefinery development. This development is achieved by the fractionation of the main components of lignocellulosic biomass (cellulose and hemicelluloses) in order to produce biofuels, molecules of interest and agromaterials.This PhD thesis had the objective to study the transformation of wheat bran xylanes into pentose based surfactants. A two steps system was studied, a first step of enzymatic hydrolysis of wheat bran with hemicellulases (to produce xylose and arabinose) and a second step of sugar acylation catalyzed by a lipase to produce pentoses based surfactants.The PhD thesis mainly focused on the transesterification of D- xylose and L-arabinose (pure or obtained from wheat bran hydrolysate) by the immobilized lipase N435 with vinyllaurate. Several parameters were studied. Lauryl mono- and diesters of D- xylose and L-arabinose were produced by the lipase and their structures were elucidated. Physico-chemical properties of the original and newly produced pentoses based esters were investigated and shown the surfactant potential of these molecules. A preliminary approach was also developed to study the enzymatic synthesis of lauryl xylo-oligosaccharides esters by the lipase N435. Our results showed that such a production is possible but is less efficient than with monosaccharides. The production by transesterification of xylo-oligosaccharides with the lipase N435 needs to be optimized as well as the purification and the characterization of lauryl xylo-oligosaccharides esters.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to evaluate the influence of different sources of carbohydrates (corn, soybean hulls and wheat bran) on ingestive behavior of twenty four steers with initial average of age and weight of 20 months and 330 kg and Charolais or Nellore predominance. The time spent in feeding activities (214min./day) and total rumination (458min./day) weren t influenced by diet carbohydrate sources. The animals in the wheat bran treatment spent less time in total idling (678min.) in relation to the corn (768min./day) and soybean hulls treatment (774min./day). The neutral detergent fiber (NDF) intake was higher for the animals fed with soybean hulls and wheat bran (5.18 and 5.42 kg/day respectively) compared with those who received corn as a carbohydrate source (3.35kg/day), however the non-fibrous carbohydrates intake was higher for this source of carbohydrate (4.29kg/day), intermediate for wheat bran (2.53kg/day) and lower for those in soybean hulls treatment. The steers fed with soybean hulls presented less intake of digestible energy (27.62Mcal/day) in relation to the corn (35. 5 Mcal/day) and wheat bran (33. 25 Mcal/day) treatments. Rumination efficiency of NDF was higher for soybean hulls (11.92g/min.) and wheat bran (10.23g/min.) compared to corn (7.68g/min.). The chewing time per ruminal bolus was lower for soybean hulls (0.88min./bolus) compared to the diets containing corn (0.96min./bolus) and wheat bran (0.95min./bolus). The animals with Charolais predominance presented higher feeding periods (29.41min.) in relation to the steers with Nellore predominance (24.95min.). The sources of carbohydrates tested didn t influence the feeding and total rumination time of the animals. The animals with Nellore predominance remain less time in lying idling, present longer periods of feeding and spend more time in chewing per ruminal bolus. / Objetivou-se, com este estudo, avaliar a influência de diferentes fontes de carboidratos (milho, casca de soja ou farelo de trigo) sobre o comportamento ingestivo de 24 novilhos castrados com idade e peso médio inicial de 20 meses e 330 kg das predominâncias Charolês ou Nelore. Os tempos despendidos com alimentação (214min./dia) e ruminação total (458min./dia) não foram influenciados pelas fontes de carboidratos. Os animais do tratamento farelo de trigo permaneceram menos tempo em ócio total (678min.) em relação ao milho (768min./dia) e a casca de soja (774min./dia). O consumo da fibra em detergente neutro (FDN) foi maior para os animais alimentados com casca de soja e farelo de trigo (5,18 e 5,42kg/dia respectivamente) comparado aos que receberam milho como fonte de carboidrato (3,35kg/dia), no entanto o consumo de carboidratos não-fibrosos foi superior para esta fonte de carboidrato (4,29kg/dia), intermediário para o farelo de trigo (2,53kg/dia) e inferior para aqueles do tratamento casca de soja. Os novilhos alimentados com casca de soja apresentaram menor consumo de energia digestível (27,62 Mcal/dia) em relação aos tratamentos milho (35,5 Mcal/dia) e farelo de trigo (33,25 Mcal/dia). A eficiência de ruminação FDN foi superior para a casca de soja (11,92g/min.) e farelo de trigo (10,23g/min.) em comparação ao milho (7,68g/min.). O tempo de mastigações por bolo ruminal foi menor para a casca de soja (0,88min./bolo) em comparação as dietas contendo milho (0,96min./bolo) e farelo de trigo (0,95min./bolo). Os animais de predominância Charolês apresentaram maiores períodos de alimentação (29,41min.) em relação aos novilhos de predominância Nelore (24,95min.). As fontes de carboidrato testadas não influenciam o tempo de alimentação e de ruminação total dos animais. Novilhos de predominância Nelore permanecem menos em ócio deitado, apresentam períodos de alimentação mais demorados e gastam mais tempo de mastigação por bolo ruminal.

Com o objetivo de avaliar a qualidade da carne de frangos recebendo dietas com inclusão de ácido fítico (AF) ou com farelo de trigo (FT) e adição ou não de fitase, foram utilizados 216 frangos de corte Cobb 500®, machos, de 22 a 35 dias de idade. O delineamento experimental foi inteiramente casualizado com 6 tratamentos e 6 repetições com 6 animais cada. Foram testadas 6 dietas: 1- dieta controle (a base de milho e farelo de soja); 2- dieta controle com adição de AF; 3- dieta com 25% de FT e sem fitase; 4- dieta com 25% de FT + 6-fitase/2500 FTU/g (fitase A); 5- dieta com 25% de FT + 6-fitase/5000 FTU/g (fitase B); 6- dieta com 25% de FT + 3-fitase/5000 FTU/g (fitase C). Os parâmetros avaliados foram: peso da carcaça, peso e rendimento dos cortes de peito, de coxa e de perna de frango, pH inicial e final da carne, cor, lipídeo total, colesterol total (CT), oxidação lipídica (TBARS), perda de peso por descongelamento (PPD), perda de peso por cocção (PPC) e força de cisalhamento (FC). Os resultados indicaram não haver interação das diferentes dietas para as respostas de: peso da carcaça, peso e rendimento dos cortes, lipídio total, PPD, PPC e pH inicial, ou seja, todas estas variáveis mostraram-se semelhantes entre as dietas testadas, conferindo uma carne de igual qualidade para estes parâmetros. Entretanto, o pH final da carne do peito foi menor para os frangos alimentados com a dieta controle (com milho e soja) que, ainda mostrou na avaliação de cor, um peito de frango com teor de amarelo (b*) mais intenso do que os apresentados pelas outras dietas. Embora tenham sido diferentes, esses dois parâmetros apresentaram valores que são considerados normais para peito de frango. A adição de AF na dieta controle promoveu um efeito muito importante na redução do colesterol total (CT) e da oxidação lipídica (TBARS) da carne de frango. E a inclusão de FT na dieta, em relação à dieta basal de frangos, ainda refletiu em teores de CT semelhantes ou menores aos obtidos por esta última dieta (dieta controle). Porém, nos valores de TBARS não ocorreu a mesma resposta, pois o FT só conseguiu ter efeito na inibição da oxidação lipídica (em relação à dieta controle) quando ele foi adicionado de fitase (mais especificamente uma 6-fitase de E. coli, definida como fitase B no presente estudo). Ao mesmo tempo, a adição desta fitase na dieta com FT, foi a que refletiu na maior força de cisalhamento (FC) dos peitos de frango entre as distintas dietas. Entretanto, o valor de FC obtido nesta dieta e nas outras, está dentro do valor considerado como macio. Ou seja, todas as dietas conferiram em uma carne de textura macia. Contudo, o FT pode ser utilizado em dietas para frangos de corte sem prejudicar as respostas de qualidade de carne. Além disso, o AF parece ser o componente responsável por diminuir o CT e a oxidação lipídica da carne de frango. / With the objective to evaluate of meat quality of broilers receiving diets with inclusion of phytic acid (PA) or wheat bran (WB) and addition or not of phytase, were used 216 Cobb 500® broilers, males, from 22 to 35 days old. The experimental design was completely randomized with six treatments and six replicates of six animals each. Six diets were tested: 1- control diet (with corn and soybeans); 2- control diet with addition of PA; 3- diet with 25% WB and without phytase; 4- diet with 25% of WB + 6-phytase/2500 FTU/g (phytase A); 5- diet with 25% of WB + 6-phytase/5000 FTU/g (phytase B); 6- diet with 25% of WB + 3-phytase/5000 FTU/g (phytase C). Were evaluated the parameters: carcass weight, cuts weight and income of chicken breast, of thigh and of on-thigh, initial and final pH of chicken, color, total lipid, total cholesterol (TC), lipid oxidation, (TBARS), weight loss by thawing (WLT), weight loss by cooking (WLC) and shear force (SF). The results showed there is not interaction of the different diets for the answers of: carcass weight, cuts weight and income, total lipid, WLT, WLC and pH initial, that is, all these variables were similar among the diets tested, resulting in an quality equal meat for these parameters. However, the final pH of breast meat was lower in chickens fed the control diet (corn and soybeans) that also showed in the evaluation of color, a chicken breast with content of yellow (b *) more intense than the presented by the other diets. Although have been different, these two parameters had values that are considered normal for chicken breast. The addition of PA in the control diet promoted a significant effect in reducing total cholesterol (TC) and lipid oxidation (TBARS) of chicken meat. And the inclusion of WB in the diet in relation to the chicken basal diet, reflected still in TC levels similar or lower to those obtained by this diet latter (control diet). However, on TBARS values did not occur the same answer, because the WB only managed to have an effect on the inhibition of lipid oxidation (in relation to the control diet) when it was added of phytase (more specifically a 6-phytase from E. coli, defined as phytase B in this study). At the same time, the addition of phytase in the diet with WB, was the which reflected in higher shear force (SF) of the chicken breasts between the different diets. However, the SF value obtained in this diet and on the other is within of the value regarded as tender. That is, all diets resulting in a soft texture meat. However, the WB can be used in diets for broilers without affecting meat quality answers. In addition, the PA seems to be the component responsible for reducing of the TC and lipid oxidation of chicken meat.

Com o objetivo de avaliar a qualidade da carne de frangos recebendo dietas com inclusão de ácido fítico (AF) ou com farelo de trigo (FT) e adição ou não de fitase, foram utilizados 216 frangos de corte Cobb 500®, machos, de 22 a 35 dias de idade. O delineamento experimental foi inteiramente casualizado com 6 tratamentos e 6 repetições com 6 animais cada. Foram testadas 6 dietas: 1- dieta controle (a base de milho e farelo de soja); 2- dieta controle com adição de AF; 3- dieta com 25% de FT e sem fitase; 4- dieta com 25% de FT + 6-fitase/2500 FTU/g (fitase A); 5- dieta com 25% de FT + 6-fitase/5000 FTU/g (fitase B); 6- dieta com 25% de FT + 3-fitase/5000 FTU/g (fitase C). Os parâmetros avaliados foram: peso da carcaça, peso e rendimento dos cortes de peito, de coxa e de perna de frango, pH inicial e final da carne, cor, lipídeo total, colesterol total (CT), oxidação lipídica (TBARS), perda de peso por descongelamento (PPD), perda de peso por cocção (PPC) e força de cisalhamento (FC). Os resultados indicaram não haver interação das diferentes dietas para as respostas de: peso da carcaça, peso e rendimento dos cortes, lipídio total, PPD, PPC e pH inicial, ou seja, todas estas variáveis mostraram-se semelhantes entre as dietas testadas, conferindo uma carne de igual qualidade para estes parâmetros. Entretanto, o pH final da carne do peito foi menor para os frangos alimentados com a dieta controle (com milho e soja) que, ainda mostrou na avaliação de cor, um peito de frango com teor de amarelo (b*) mais intenso do que os apresentados pelas outras dietas. Embora tenham sido diferentes, esses dois parâmetros apresentaram valores que são considerados normais para peito de frango. A adição de AF na dieta controle promoveu um efeito muito importante na redução do colesterol total (CT) e da oxidação lipídica (TBARS) da carne de frango. E a inclusão de FT na dieta, em relação à dieta basal de frangos, ainda refletiu em teores de CT semelhantes ou menores aos obtidos por esta última dieta (dieta controle). Porém, nos valores de TBARS não ocorreu a mesma resposta, pois o FT só conseguiu ter efeito na inibição da oxidação lipídica (em relação à dieta controle) quando ele foi adicionado de fitase (mais especificamente uma 6-fitase de E. coli, definida como fitase B no presente estudo). Ao mesmo tempo, a adição desta fitase na dieta com FT, foi a que refletiu na maior força de cisalhamento (FC) dos peitos de frango entre as distintas dietas. Entretanto, o valor de FC obtido nesta dieta e nas outras, está dentro do valor considerado como macio. Ou seja, todas as dietas conferiram em uma carne de textura macia. Contudo, o FT pode ser utilizado em dietas para frangos de corte sem prejudicar as respostas de qualidade de carne. Além disso, o AF parece ser o componente responsável por diminuir o CT e a oxidação lipídica da carne de frango. / With the objective to evaluate of meat quality of broilers receiving diets with inclusion of phytic acid (PA) or wheat bran (WB) and addition or not of phytase, were used 216 Cobb 500® broilers, males, from 22 to 35 days old. The experimental design was completely randomized with six treatments and six replicates of six animals each. Six diets were tested: 1- control diet (with corn and soybeans); 2- control diet with addition of PA; 3- diet with 25% WB and without phytase; 4- diet with 25% of WB + 6-phytase/2500 FTU/g (phytase A); 5- diet with 25% of WB + 6-phytase/5000 FTU/g (phytase B); 6- diet with 25% of WB + 3-phytase/5000 FTU/g (phytase C). Were evaluated the parameters: carcass weight, cuts weight and income of chicken breast, of thigh and of on-thigh, initial and final pH of chicken, color, total lipid, total cholesterol (TC), lipid oxidation, (TBARS), weight loss by thawing (WLT), weight loss by cooking (WLC) and shear force (SF). The results showed there is not interaction of the different diets for the answers of: carcass weight, cuts weight and income, total lipid, WLT, WLC and pH initial, that is, all these variables were similar among the diets tested, resulting in an quality equal meat for these parameters. However, the final pH of breast meat was lower in chickens fed the control diet (corn and soybeans) that also showed in the evaluation of color, a chicken breast with content of yellow (b *) more intense than the presented by the other diets. Although have been different, these two parameters had values that are considered normal for chicken breast. The addition of PA in the control diet promoted a significant effect in reducing total cholesterol (TC) and lipid oxidation (TBARS) of chicken meat. And the inclusion of WB in the diet in relation to the chicken basal diet, reflected still in TC levels similar or lower to those obtained by this diet latter (control diet). However, on TBARS values did not occur the same answer, because the WB only managed to have an effect on the inhibition of lipid oxidation (in relation to the control diet) when it was added of phytase (more specifically a 6-phytase from E. coli, defined as phytase B in this study). At the same time, the addition of phytase in the diet with WB, was the which reflected in higher shear force (SF) of the chicken breasts between the different diets. However, the SF value obtained in this diet and on the other is within of the value regarded as tender. That is, all diets resulting in a soft texture meat. However, the WB can be used in diets for broilers without affecting meat quality answers. In addition, the PA seems to be the component responsible for reducing of the TC and lipid oxidation of chicken meat.

Orientador: Caroline Joy Steel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-08T05:07:57Z (GMT). No. of bitstreams: 1 Ferreira_ReinaldoEduardo_M.pdf: 3044163 bytes, checksum: f704bd363854b3c9458130c70bece72a (MD5) Previous issue date: 2006 / Mestrado / Mestre em Tecnologia de Alimentos

Establishing a commercial, lignocellulose-based, second-generation ethanol process has received several decades of attention by both researchers and industry. However, a fully economically viable process still remains a long-term goal. The main bottleneck to this achievement is the recalcitrance of lignocellulosic feedstocks, although there are several other factors, such as the huge investment required for second-generation ethanol facilities. An intelligent alternative solution discussed in this thesis is an integrated approach using firstgeneration ethanol plants for second-generation processes. Wheat is the major feedstock for first-generation ethanol in Europe; therefore, wheat-based lignocellulose waste, such as wheat straw, bran, and whole stillage fiber (a waste stream from first-generation wheat-based ethanol plants) was the primary focus of the integration model in this thesis. Since the major share of first-generation ethanol plant economics focuses on the animal feed DDGS (Distillers’ dried gains with solubles), the integration of lignocellulose should be designed in order to maintain DDGS quality. An ethanol-producing edible filamentous fungus, Neurospora intermedia, a potential protein source in DDGS, was considered for use as the fermenting microbe. The morphological and physiological aspects of this fungus were studied in the thesis, leading to the first report of fungal pellet development. An alternative approach of using dilute phosphoric acid to pretreat lignocellulose, as it does not negatively affect fungal growth or DDGS quality, was demonstrated in both the laboratory and on a 1m3 pilot scale. Furthermore, the process of hydrolysis of pretreated lignocelluloses and subsequent N. intermedia fermentation on lignocellulose hydrolysate was also optimized in the laboratory and scaled up to 1 m3 using an in-house pilot-scale airlift bioreactor. Fungal fermentation on acid-pretreated and enzyme-hydrolyzed wheat bran, straw and whole stillage fiber resulted in a final ethanol yield of 95%, 94% and 91% of the theoretical maximum based on the glucan content of the substrate, respectively. Integrating the first- and second-generation processes using thin stillage (a waste stream from first-generation wheat-based ethanol plants) enhanced the fungal growth on straw hydrolysate, avoiding the need for supplementing with extra nutrients. Based on the results obtained from this thesis work, a new model for integrated first- and second-generation ethanol using edible filamentous fungi processes that also adds value to animal feed (DDGS) was developed.

Submitted by (edna.saturno@ufrpe.br) on 2017-02-22T12:49:09Z No. of bitstreams: 1 Susmara Silva Campos.pdf: 2667117 bytes, checksum: aae2333b8a561bd3d809160a8d74a179 (MD5) / Made available in DSpace on 2017-02-22T12:49:09Z (GMT). No. of bitstreams: 1 Susmara Silva Campos.pdf: 2667117 bytes, checksum: aae2333b8a561bd3d809160a8d74a179 (MD5) Previous issue date: 2005-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The shrimp Litopenaeus vannamei adapted itself very well to the culture conditions in the Northeast due to their characteristics of tolerance to the salinity and temperature, resistance to the handling, rapid growth and survival and good feed conversion, contributing to place Brazil in the producer and exporter market. Even with the good productivity results, there are some limiting factors to be better studied, as the feeding, where the production and the adequate management of the natural food contributing to improve the economical and environmental feasibility of the culture and represents great nutritional importance to the cultivated organisms. The aim of this study was to analyze the influence of organic fertilizer in the availability of natural food (plankton and benthos) and the shrimp growth, with the purpose of effluents and costs reduction, through two fertilization regimes in four treatments: 1) CP: Control (inorganic fertilizers) stocked with 40 juveniles.m-2; 2) CNP: Control no-shrimp; 3) TP: Wheat bran (organic fertilizer) stocked with 40 juveniles.m-2; 4) TNP: Wheat bran no-shrimp, with three replicates each. The experimental tanks were prepared with sediment, individual aeration, without water exchange, and the shrimps feeding during 88 culture days, was done with a commercial 35% crude protein ration through feeding trays, three times a day, adjusted daily to the according consumption. The water temperature, dissolved oxygen and pH were measured daily; the transparency and salinity were checked weekly and samples of water of each tank were collected biweekly for nutrients analyses. The phytoplankton analysis, zooplankton, phytobenthos and meiobenthos samples were accomplished biweekly and macroinvertebrates samples were monthly. The dissolved oxygen levels were higher with the wheat bran (6.16±0.98 mg.L-1) than with the inorganic fertilizers (5.92±1.19 mg.L-1). Under organic fertilization regime, the phytoplankton presented abundance of Bacillariophyceae, mainly Nitzschia, and rotifers; the phytobenthos was constituted of Bacillariophyceae, mainly for Nitzschia, Amphiprora and Cymbella; the meiobenthos mainly for nematodes and rotifers; and the macroinvertebrates were constituted mainly of oligochaetas. The feeding preference of the shrimps was decisive in the abundance of natural food, which determined different conversion ration along the experiment (1.3 and 2.1), justifying periodic adjustments of the amount of artificial diets. The shrimps survival was the same for both fertilization regimes (96.6%). The final weight in CP was of 11.89±1.73 g and in TP was of 12.28±1.71 g, with lower cost of the wheat bran in relation to the inorganic fertilizers. The wheat bran showed better performance not only in the water quality maintenance without exchange but also in the availability of natural food, and the performance of the shrimps, contributing to the minimize shrimp culture effluents and its impact on the environment, also in the reduction of the production costs. / O camarão Litopenaeus vannamei adaptou-se muito bem às condições de cultivo na região Nordeste devido as suas características de ampla faixa de tolerância à salinidade e temperatura, resistência ao manuseio, altas taxas de crescimento e de sobrevivência e boa conversão alimentar, contribuindo para colocar o Brasil no mercado produtor e exportador. Mesmo com os bons resultados de produtividade alcançados, ainda há fatores limitantes a serem mais bem estudados, como a alimentação, onde a produção e o manejo adequado do alimento natural contribuem para melhorar a viabilidade econômica e ambiental do cultivo e representa grande importância nutricional para os organismos cultivados. O presente trabalho teve por objetivo analisar a influência de fertilizante orgânico na disponibilidade de alimento natural (plâncton e bentos) e no crescimento do camarão, com a finalidade de redução dos efluentes de cultivos e dos custos de produção, através de dois regimes de fertilização em quatro tratamentos: 1) CP: Controle (fertilizantes inorgânicos) povoado com 40 juvenis.m-2; 2) CNP: Controle não-povoado; 3) TP: Farelo de trigo (fertilizante orgânico) povoado com 40 juvenis.tanque-2; 4) TNP: Farelo de trigo não-povoado; com três repetições cada. Os tanques experimentais foram preparados com sedimento, aeração individual, sem troca de água, e a alimentação dos camarões, durante 88 dias de cultivo, foi feita através de comedouros, com ração comercial com 35% de proteína bruta, três vezes ao dia, ajustada diariamente em função do consumo. A temperatura da água, oxigênio dissolvido e pH foram mensurados diariamente; a transparência e salinidade foram aferidas semanalmente e amostras de água de cada tanque foram coletadas quinzenalmente para as análises de nitrato, nitrito, amônia total, ortofosfato, silicato, alcalinidade e clorofila a. As coletas para análise de fitoplâncton, zooplâncton, fitobentos e meiobentos foram realizadas quinzenalmente e as coletas de macro-invertebrados foram mensais. Quanto à qualidade da água, os níveis de oxigênio dissolvido foram mais elevados com o farelo de trigo (6,16±0,98 mg.L-1) do que com os fertilizantes inorgânicos (5,92±1,19 mg.L-1). Sob fertilização orgânica, o fitoplâncton apresentou abundância de Bacillariophyceae, principalmente Nitzschia, e rotíferos; o fitobentos esteve constituído de Bacillariophyceae, principalmente por Nitzschia, Amphiprora e Cymbella; o meiobentos principalmente por nematódeos e rotíferos; e os macro-invertebrados constituíram-se principalmente de oligoquetas. A preferência alimentar dos camarões foi determinante na abundância de alimento natural o qual, por sua vez, determinou conversão alimentar diferente ao longo do experimento (1,3 e 2,1), justificando reajustes periódicos da quantidade de ração fornecida. A sobrevivência dos camarões foi a mesma para ambos os regimes de fertilização (96,6%). O peso final no CP foi de 11,89±1,73 g e no TP foi de 12,28±1,71 g, com menor custo do farelo de trigo em relação aos fertilizantes inorgânicos. O farelo de trigo apresentou bom desempenho tanto na manutenção da qualidade da água sem renovação e na disponibilidade de alimento natural, como no desenvolvimento dos camarões, desta forma podendo contribuir para a minimização dos efluentes da carcinicultura e seu impacto sobre o ambiente, bem como na redução dos custos de produção.

Gastrointestinal microflora has been shown to have a bi-directional relationship with the host immune system. A variety of fermentable carbohydrate polymers largely pass through the small intestine, providing fermentable substrates for gut microflora. Dietary fibre supplementation may provide a strategy for manipulating the intestinal bacterial profile, changing the interaction with the mucosal immune system, thereby modulating the host immune system. We used a BBc rat animal model to evaluate the effects of oat bran and wheat bran dietary fibre on the immune system. Previous collaborative efforts have shown that these dietary fibres can change the intestinal microflora, with wheat bran fibre showing a greater ability to influence colonic microbial community diversity. We have shown that dietary wheat bran fibre led to reduced IL-4 levels in the liver and T lymphocyte numbers in the Mesenteric Lymph Node and may be involved in reduced IgA levels in the cecal contents. In addition, IgA in the cecal contents was decreased while MLN B cell numbers increased in response to dietary wheat bran fibre. It was observed that neither wheat bran or oat bran treatments exerted any pro-inflammatory effects, with oat bran actually improving antioxidant status. These results suggest that both oat and wheat bran fibre treatments induce changes in the intestinal microflora, and that the microflora changes due to wheat fibre are associated with immunomodulatory effects on the host. This type of dietary fibre supplementation could ultimately provide a potential strategy for promoting health through microflora-associated effects on the immune system.

Parmi les méthodes alternatives respectueuses de l'environnement pour la lutte contre les ravageurs et la protection des cultures agricoles, les bioinsecticides à base de Bacillus thuringiensis sont les plus largement utilisés. L’activité insecticide de B.thuringiensis réside dans la production d’inclusions cristallines protéiques appelées δ-endotoxines qui sont formées au cours de la sporulation. En préalable à ces travaux, de nouvelles souches de B.thuringiensis ont été isolées du sol libanais et ont montré un potentiel insecticide élevé, supérieur à des souches classiquement utilisées. Dans le cadre du développement d'une production industrielle, au Liban, de biopesticides à base de ces souches de B.thuringiensis, ce travail a visé à optimiser la production des δ-endotoxines afin d'augmenter les rendements et de réduire les coûts de production. A l'échelle industrielle, le milieu de culture des bactéries représente une part importante du coût de production. Ainsi, l'effet, sur la concentration des δ-endotoxines, de substitution des sources synthétiques coûteuses d'azote, de carbone et de minéraux, par un sous-produit de la minoterie de blé (le son de blé) a été étudié. L’efficacité de ce sous-produit agro-industriel comme source complète de nutriments, disponible localement à faible prix, a été prouvée pour des fermentations submergées de deux souches différentes toxiques contre des diptères ou des lépidoptères. La comparaison du milieu son de blé à d’autres milieux (synthétiques ou non), classiquement utilisés en bibliographie, a montré que ce milieu présente de nombreux avantages en termes de productivité, de rendement relatif des δ-endotoxines et de coût. Parallèlement à ce travail, une méthode simple et rapide de purification des cristaux a été développée de façon à obtenir des cristaux protéiques purs à 99 % nécessaires comme standards pour le dosage des cristaux dans le milieu de fermentation. Un autre objectif du travail a été d’analyser l'effet de l'aération sur la cinétique de croissance et de sporulation d'une nouvelle souche de B.thuringiensis var kurstaki. Les différentes conditions d’aération testées en fermenteurs de 2 L, caractérisées par le coefficient volumétrique de transfert de dioxygène (KLa), ont permis de montrer l’importance de ce paramètre et de l’optimiser pour obtenir la meilleure productivité en biopesticides. Le meilleur rendement en protéines de toxines a été obtenu dans un milieu son de blé 6 % (masse/volume) dans des conditions d’aération correspondant à un KLa de 65,5 h-1 alors que la meilleure productivité des protéines de toxines a été atteinte dans le milieu 9 % pour un KLa de 102 h-1. Sur la base de cette étude, le dimensionnement de la production de B.thuringiensis à l’échelle 1000 L a été réalisé. L’unité de production a été construite et les premiers essais réalisés ont permis de produire de façon satisfaisante des lots de biopesticides. L’ajustement des protocoles industriels reste à faire. / Among the safe and environment friendly methods for the fight against pests and agricultural crops protection, Bacillus thuringiensis based biopesticides are the most widely used. The insecticidal activity of B. thuringiensis resides in the production of protein crystal inclusions called δ-endotoxins, which are formed during sporulation. Preliminary to this work, new B. thuringiensis strains were isolated from Lebanese soil and showed higher insecticidal potential than the conventionally used strains. As part of the development of an industrial production, in Lebanon, of biopesticides based on these strains of B.thuringiensis, this work aimed to optimize the production of δ-endotoxins to increase yields and reduce the cost of mass production. At industrial scale, the bacteria culture medium represents a significant part of the production cost. Thus, the effect on the concentration of the δ-endotoxins, of substituting expensive synthetic sources of nitrogen, carbon, and minerals, with a byproduct of wheat mill (wheat bran) was studied. The effectiveness of this agro-industrial by-product available locally at low prices, as complete source of nutrients, in submerged fermentations of two different strains of B.thuringiensis toxic against Lepidoptera and Diptera, has been proven. The comparison of the wheat bran medium to other mediums (synthetic or not), conventionally used in the bibliography, has shown that this medium this medium has many advantages in terms of productivity, relative yield of δ-endotoxins and cost. In parallel to this work, a simple and quick method of crystal purification was developed to obtain pure protein crystals to 99 % required as standards for the determination of crystals concentration in the fermentation medium. Another objective of the study was to analyze the effect of aeration on growth and sporulation kinetics of a new strain of B.thuringiensis var kurstaki. The different aeration conditions tested in fermenters of 2 L, characterized by the volumetric oxygen transfer coefficient (KLa), permitted to show the importance of this parameter and to optimize it to get the best biopesticides productivity. The best yield of toxin proteins relative to the wheat bran ratio in the culture medium was obtained in the 6 % (weight/volume) medium in aeration conditions corresponding to a KLa of 65.5 h-1, while the highest productivity of toxin proteins has been reached in the 9 % medium for KLa of 102 h-1. On this study basis, the scale up of B. thuringiensis production was performed in a bioreactor of 1000 L. The production unit was built and the first tests carried out have produced satisfactory batches of biopesticides. Industrial protocols are still to be adjusted.