Дисертації з теми "Hydrolysats de protéines de pois"
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Irankunda, Rachel. "Nickel Chelating Peptides & Chromatography : From Peptides Separation Simulation up to their Antioxidant Activities - related Applications." Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0213.
Metal-Chelating Peptides (MCPs), from protein hydrolysates, present various applications in nutrition, pharmacy, cosmetic etc. Yet, the empirical approach generally used to discover bioactive peptides from hydrolysates is time consuming and expensive due to many steps of fractionation, separation and biological activities evaluation. Thus, this PhD aimed to develop a novel approach for MCPs separation prediction using chromatography modelling and simulation based on the analogy between Immobilized Metal ion Affinity Chromatography (IMAC) and Surface Plasmon Resonance (SPR). For the first time, the SPR-IMAC analogy was experimentally investigated on 22 peptides and 70% of them validated this analogy, since peptides well retained in IMAC were also endowed with a good affinity for Ni2+ in SPR. In the second time, peptides with high affinity for Ni2+ (i.e low dissociation constant KD in SPR and a high retention time in IMAC) were used to study the modelling and simulation of peptide concentration profiles at the column outlet in IMAC. Since knowledge of adsorption isotherms was required to perform simulation, it was necessary to develop a methodology for predicting Langmuir isotherm parameters in IMAC from SPR data. The validity of simulation was evaluated by comparing experimental and simulated retention times that should be close for reliable prediction. Therefore, several approaches were evaluated to determine Langmuir sorption parameters, the most interesting one introduces a correction factor on the maximum adsorption capacity qmax alone, assuming that the affinity of peptides for immobilized Ni2+ did not change depending on the technology used (SPR vs. IMAC), thus affinity constant KA was not modified. Meanwhile, industrial application of MCPs and hydrolysates were studied. First, pea protein hydrolysates were produced by either Alcalase® followed by Flavourzyme® (Alc+Flav≤1kDa) or Protamex® followed by Flavourzyme® (Prot+Flav≤1kDa). SwitchSENSE® technology evidences the presence of Ni2+ chelating peptides and antioxidants tests showed that Prot+Flav≤1kDa has higher radical scavenging and reducing power, related to its higher degree of hydrolysis and small-size peptides quantity. Secondly, pea hydrolysates and MCPs were investigated for their ability to inhibit the lipid oxidation in emulsions. They slowed down lipid oxidation through chelation of prooxidant (metals such as Fe2+) reducing primary and secondary oxidation products responsible of deterioration of lipid containing products. Thus, pea hydrolysates and MCPs could be used as antioxidants in food and cosmetic products, as alternative to chemicals such as EDTA, BHT and TBHQ
Le, Coeur Catherine. "Contribution à l'étude d'un hydrolysat pepsique de myoglobine de muscle squelettique rouge de thon Thunnus Albacares : caractérisation des peptides issus de l'hydrolyse étude de l'association hème-peptide." La Rochelle, 1996. http://www.theses.fr/1996LAROS011.
Ravallec, Rozenn. "Valorisation d'hydrolysats d'origine marine : optimisation de la concentration en peptides apparentés aux facteurs de croissance et aux agents sécrétagogues : essais in vitro et in vivo." Brest, 2000. http://www.theses.fr/2000BRES2041.
BANIEL, ALAIN. "Etude de la variabilite genotypique et phenotypique de la composition proteique du pois (pisum sativum l. )." Nantes, 1993. http://www.theses.fr/1993NANT2011.
BEN-HDECH, EL-HASSANE. "Texturation d'une farine de pois par cuisson-extrusion : caracterisation microstructurale, ultrastructurale et physico-chimique." Nantes, 1993. http://www.theses.fr/1993NANT2014.
TAMELIKECHT, HINDI FATMA. "Hydrolyse enzymatique de la fraction hydrosoluble des proteines de pois chiche (cicer arietinum) par la bromelaine et l'alpha-chymotrypsine ; caracterisation des hydrolysats et etude de leur immunogenicite." Paris 5, 1996. http://www.theses.fr/1996PA05N125.
Chabanon, Gérald. "Hydrolyses enzymatiques d'isolats protéiques issus de tourteaux de colza : cinétique, modélisation, caractérisation et fonctionnalité des peptides." Vandoeuvre-les-Nancy, INPL, 2005. http://docnum.univ-lorraine.fr/public/INPL/2005_CHABANON_G.pdf.
This thesis made it possible to study obtaining biologically active peptides or with functional properties through the development of processes for the preparation and the hydrolysis of protein isolates resulting from rapeseed cakes. First, a method of preparation of two protein isolates being different by the type of proteins (Globulin or Albumin) was developed. The two isolates do not have good functional properties but their partial hydrolysis by Alcalase 2. 4L improves some of them. Then, the hydrolytic action of commercial proteases (Alcalase 2. 4L, Pronase SG, Neutrase 0. 8L, Prolyve BS, Lypaïne 6500, Orientase 90N, Espérase 7. 5L) on the isolate of globulins was compared. The valorisation of the hydrolysates related to their capacity to promote the growth of animal cells cultivated in a serum-free medium. It was shown that the kinetics of hydrolysis, the size of produced peptides and the biological activity of the hydrolysates are significantly influenced by the specificity of the enzyme and there is a relation enzyme/ degree of hydrolysis (DH)/ targeted activity. Lastly, we showed for three different enzyme/substrate systems (Alcalase / Globulin, Pronase / Globulin and Alcalase / Albumin) that at given DH and pH, the peptide composition of the hydrolysates is independent of the initial enzyme and substrate concentrations and of the temperature. Thus, the prediction of the temporal evolution of the DH, whatever the values of precedent parameters, allows to control the generation of a peptide mixture with targeted properties. A model based on the reaction pathway of Michaelis-Menten was then built in order to simulate the hydrolysis kinetics in batch reactor. For that, limiting phenomena implied in the hydrolysis (inhibition or inactivation of the enzyme, modification of the substrate) were highlighted
Gharsallaoui, Adem. "Microencapsulation séquentielle d'un système lipidique par des biopolymères végétaux (protéines de pois et pectine) : influence des interactions à l'interface huile / eau." Dijon, 2009. http://www.theses.fr/2009DIJOS053.
The protection and the vectorization of active, food and pharmaceutical molecules, require separating them from their environment by entrapping them in structured matrices able to release them at the precise place and the quite time. When these encapsulation systems are based on dry emulsions, the control of the matrices requires the knowledge of both the properties of the interfacial membranes and those of the drying matrix. The characterization, of the interfacial properties of pea proteins, in presence and absence of pectin, an anionic polyelectrolyte, allows the study of the interactions proteins/pectin at O/W interfaces and their effect on the emulsion stability during spray-drying process. The study of the effect of the properties of the dehydration matrix, maltodextrins, makes it possible to link their interactions with water to the encapsulation efficiency of dry emulsions. The molecular investigation highlights the role of pectin in the stabilization of the secondary structure of pea globulins during drying, which results in a better protection of the encapsulated active molecule. Lastly, the analysis of the release kinetics of a volatile molecule makes it possible to evaluate the barrier properties of the interfacial layers and to identify the release mechanism. The whole of this work at various scales makes it possible to contribute to the understanding of the various mechanisms implied in the emulsion stabilization by multi-layered interfaces containing proteins/polysaccharides, their resistance to spray-drying and finally their capacity to protect fragile compounds
Duval, Frédéric. "Calmodulines et germination chez le pois (Pisum sativum L. ) : aspects biochimiques et moléculaires." Angers, 2002. http://www.theses.fr/2002ANGE0042.
Gauvin, Laurence. "Contribution à l'étude de l'extraction des protéines de pois chiche ("Cicer arietinum") en vue d'une application industrielle." Paris 5, 1994. http://www.theses.fr/1994PA05P057.
Debrabant, Alain. "Étude de la protéolyse de la protéine P126 de Plasmodium falciparum." Lille 1, 1990. http://www.theses.fr/1990LIL10067.
Odoux, Eric. "Contribution à l'étude de l'hydrolyse de la glucovanilline en vanilline dans la "gousse" du vanillier (vanilla planifolia G. Jackson)." Montpellier 2, 2004. http://www.theses.fr/2004MON20057.
Prévôt-d'Alvise, Nathalie. "Mise au point d'un procédé d'hydrolyse enzymatique de protéines de luzerne (Medicago sativa var. Europe) dans un réacteur à membrane et extrapolation à l'échelle pilote." Lille 1, 2000. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2000/50376-2000-47.pdf.
Gevrey, Jean-Claude. "Mécanismes de réponse de la cellule endocrine intestinale aux hydrolysats protéiques : aspects sécrétoire et transcriptionnel." Lyon 1, 2002. http://www.theses.fr/2002LYO1T170.
Le, Gall Maud. "Digestion des protéines de pois chez le porcelet et le porc en croissance : carctérisation des peptides résistants à la digestion." Rennes, Agrocampus Ouest, 2004. http://www.theses.fr/2004NSARB161.
The incorporation of pea in animal feed is limited by the low nutritional quality of the raw meal. This has long been ascribed to the presence of a limiting amount of essential sulphur amino acids and the poor digestibility of proteins caused by the presence of antinutritional factors in the seed. Our studies showed that the major pea storage proteins, globulins, are well digested in the pig. The α polypeptide of legumin is totally hydrolysed by pepsin while the β polypeptide and vicilin are digested by pancreatic and intestinal enzymes only. Proteins from the albumin fraction are more resistant to digestion. The lectin and the albumin PA1b are totally resistant in the gastrointestinal tract. By contrast, the susceptibility of the major albumin PA2 to digestion is influenced by different factors. It is totally hydrolysed by pepsin while being partly resistant to pancreatic and intestinal enzymes. Consequently, for a gastric retention time below 3 hours, a cleaved PA2 peptide of 15 kDa escapes gastric and small intestinal digestion. Pea particle size reduction and heating enhance susceptibility to digestion by increasing protein accessibility to enzymes
Djoullah, Attaf. "Réticulation enzymatique des protéines de pois pour la formation de microparticules : application à l'encapsulation de la riboflavine." Thesis, Dijon, 2015. http://www.theses.fr/2015DIJOS072/document.
In this work, pea proteins behavior toward enzymatic gelation by microbial transglutaminase (MTGase) was studied at native state and after denaturation (chemical reduction or thermal denaturation). The final application was the formation of protein microparticules to encapsulate riboflavin, chosen as hydrophilic active molecule model. The extraction process of the pea protein fractions has been optimized in such a way to minimize as possible protein denaturation and recover native fractions rich in albumin (Alb) and globulin (Glob) or a mixture of both.The setting up of the enzymatic reaction monitoring methods has brought out their complementarity as well as their limits. Two new monitoring methods of enzymatic cross-linking reaction have been developed. The first one, based on the NMR, allows to the simultaneous determination of the glutamine-lysine isopeptide bond, product of the enzymatic reaction, and the degree of crosslinking; the second method, based on size measuring techniques (SDS-PAGE and DLS), permit to view the intramolecular links. The study of enzymatic treatment applied to pea Alb and Glob at the native and denatured states, as well as thier native mixture showed that the enzymatic reaction is strongly related to the structure and conformation of proteins. Unlike Alb, the Glob fraction is a good substrate to transglutaminase and crosslinking reaction involves different subunits constituting globulins for each treatment condition. However, the Alb can be used as a booster of enzyme reaction which can be an innovative way for improving the proteins susceptibility toward transglutaminase treatment. The mechanism seems to be based on a selective affinity phenomenon. The good mechanical properties and water holding capacity of total pea proteins gel have been exploited to produce microparticles from a water-in-oil emulsion followed by enzymatic gelation. The produced microparticles were practically insoluble in gastrointestinal media in the absence of enzymes and slowly degradable in the presence of enzymes. The release mechanisms of riboflavin in digestive environments are governed by a diffusion phenomenon in the absence of enzymes and by support degradation phenomenon in the presence of enzymes according to kinetics compatible with nutraceutical applications
Moyne, Pascale. "Contribution à l'étude de l'apport azoté en nutrition parentérale par des hydrolysats enzymatiques de protéines du lait de vache." Montpellier 1, 1994. http://www.theses.fr/1994MON13510.
Vinot-Renaud, Catherine. "Contribution à la connaissance et à la valorisation d'hydrolysats industriels de protéines de poissons." Compiègne, 1989. http://www.theses.fr/1989COMPD208.
Robert, Marie. "Développement d'hydrolysats pour l'alimentation des animaux d'aquaculture : caractérisation moléculaire et fonctionnelle." Caen, 2014. http://www.theses.fr/2014CAEN2050.
Global production of farmed fish and shrimp has grown dramatically over the past decades and now contributes to half of the aquatic products intended for human consumption. Aquaculture is a key sector for the maintenance and improvement of food security worldwide. However, its rapid growth has a significant impact on the environment, particularly on the stocks of wild fish used to produce aqua feed. In this context, aqua feed has dramatically evolved and has been adapted to many economic and environmental constraints. The use of fishmeal has particularly declined in favor of plant protein sources. But plant proteins are less adapted to the nutritional needs of fish and result in lower growth performances. Protein hydrolysates from fishing and aquaculture by-products are ingredients of high nutritional and bioactive potential developed to restore growth performances in high-level plant protein diets. They are rich in hydrolytic peptides and free amino acids, but they are complex mixtures whose composition is not well known. We developed an experimental approach to characterize the peptide fraction of two by-product hydrolysates based on two complementary approaches: a transcriptomics approach aimed at getting transcriptomics data about the targeted by-products, and a peptidomics approach. The peptidomics approach combined the optimization of fractionation steps and two complementary mass spectrometry techniques. Thus we identified more than 1,000 peptides in the two by-product hydrolysates. Furthermore, diet conditioning experiments conducted in sea bass, Dicentrarchus labrax, highlighted their interesting nutritional properties to maintain growth performances of farmed fish. Indeed, dietary inclusion of 5\% of these hydrolysates in a high-level plant protein diet (95%) maintained growth performances at similar levels to those obtained with diets containing 80% of plant protein. In addition, we demonstrated an influence of these by-product hydrolysates on the digestive physiology of sea bass, as shown by biomarker expression in the intestinal absorption profiles observed in the study. Finally, our work shows that (i) both hydrolysates possess in vitro antibacterial activity and (ii) tilapia hydrolysate stimulates the immune system of sea bass. These results demonstrate the interest of using these two hydrolysates in aquaculture in addition to or instead of fishmeal
Grelet, Johann. "Identification et caractérisation moléculaire d'une protéine LEA (Late Embryogenesis Abundant) mitochondriale exprimée dans les semences de pois." Angers, 2004. http://www.theses.fr/2004ANGE0020.
LEA (Late Embryogenesis Abundant) proteins belong to a large hydrophilic heat-resistant family, and exhibit repeated motifs in their sequence. The LEA proteins accumulate during seed maturation and disappear upon germination. A number of LEA proteins have been shown to also accumulate in plant tissues in response to ABA and numerous stresses. All the above characteristics support the idea that LEA proteins are involved in desiccation tolerance. They were found in many sub-cellular compartments: nucleus, chloroplasts, cytosol, endoplasmique reticulum, Golgi apparatus. . . But no LEA protein has been described in mitochondria so far. In a survey of pea mitochondrial proteome, a putative seed mitochondrial protein exhibited peptide tag sequence similarities with a soybean LEA-like protein (Bardel et al, 2002). The cDNA encoded this protein (PsLEAm) was cloned and revealed a typical amino-terminal transit peptide in the protein sequence. Biochemical evidence and GFP reporter transient expression in protoplast indicated that PsLEAm was localized in mitochondria matrix space. PsLEAm exhibited most of the LEA family features: heat solubility, high hydrophilicity, repeated motives and accumulation during late maturation. Moreover, exogenous ABA application during seed imbibition and severe water stress in mature plants re-induced PsLEAm expression. To explore the function of PsLEAm in mitochondria, a recombinant mature PsLEAm was overexpressed in Escherichia coli and was then partially purified. The recombinant protein was shown to protect two mitochondrial matrix enzymes, fumarase and rhodanese, during drying in an in vitro assay. Our future efforts will be focused on structural and functional analyses of PsLEAm, which will be a step forward to understanding the protective role that PsLEAm during seed maturation
Kriaa, Habib. "Enrichissement du son en protéines par fermentation." Compiègne, 1989. http://www.theses.fr/1989COMPD282.
Proteins are very important for human food. Nevertheless the world shortage in protein is increasing despite all the efforts made to improve productivity of vegetable protein sources. In Tunisia, the bran of the corn is a very abundant raw material. This substrate is poor in proteins, however because of its richness in starch (25 - 30%), this raw material can be enriched in proteins of unicellular organisms in particular by yeast culture. To reach this objective, we’ve used an enzymatic method transforming the starch of the bran in a fermentiscible sugar. The use of amylotic enzymes has allowed us to transform starch in simple sugar with a yield of 95%. The hydrolysate thus obtained has been tested as a culture medium for the growth of Hansenula anomala in batch and continue culture to its enrichment in proteins. The use of that enzymatic hydrolysate of the starch of the bran at 20 (g/l) of glucose for the growth of Hansenula anomala in a closed reactor has led to the following kinetic characteristics : a specific maximal speed : max(x)=0,25h-1 and a protein yield Y(P/s)=22%. The continue culture of this strain on the bran hydrolysate in the same conditions has led to the deduction of the following kinetic characteristics : max(x)=0,3h-1 with a protein yield Y(P/s)=23%
Rakotozafy, Randrianasolo Lalatiana Rasata. "Application de réactions enzymatiques énantiosélectives au dédoublement de synthons chiraux utilisables dans l'industrie pharmaceutique ou en chimie fine." Paris 6, 1991. http://www.theses.fr/1991PA066301.
Tolleter, Dimitri. "Analyse structurale et fonctionnelle d'une protéine LEA (Late Embryogenesis Abundant) mitochondriale exprimée dans les graines de pois." Phd thesis, Université d'Angers, 2007. http://tel.archives-ouvertes.fr/tel-00346312.
Dion-Poulin, Alexandra. "Étude de la fonctionnalité d’hydrolysats protéiques d’insectes générés par le couplage de l’hydrolyse enzymatique et des hautes pressions hydrostatiques et de l’acceptabilité d’un ingrédient d’insectes auprès de cuisiniers novateurs." Master's thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/68780.
Interest in Entomophagy increases due to several environmental and nutritional benefits, but the social acceptability of this practice is a major obstacle in Western societies. Studies have shown that incorporating insect as an ingredient rather than whole insects promotes consumer acceptability. As a result of their poor functionality, insect meals arecommonly used as a filler agent. Enzymatic hydrolysis is a widely used method to modify and improve the functionality of various proteins, but the effectiveness of this method can be enhanced by using high hydrostatic pressures (HHP) as a pre-treatment. In this project, the functionality of insect meals and protein hydrolysates prepared from meals that were pretreated or not prior enzymatic hydrolysis by pressurization has been determined. The solubility and oil binding capacity were enhanced by this process in contrast to water binding capacity as well as foaming and gelling properties. Viscosity and emulsifying property were slightly increased comparatively to insect meal. However, their different functionalities from those of insect meals could facilitate their acceptability. Specifically, it is acknowledged thata positive consumption experience promotes the entomophagy acceptability especially whenchefs are included in the process. For this project a qualitative study based a priori on Roger’sdiffusion of innovation theory was also conducted to explore the perceptions of innovative chefs on the use of insect ingredients. All participants had a positive opinion of entomophagy and the majority was ready to use it. Understanding these perceptions will increase the use of insect ingredients in the gastronomy and eventually social acceptability.
Dumont, Estelle. "Tolérance au gel après acclimatation au froid chez le pois : identification de protéines et cartographie de PQL et QTL." Thesis, Lille 1, 2008. http://www.theses.fr/2008LIL10037/document.
CoId acclimation is the process whereby plants, previously exposed to low positive temperatures, are sUbsequently able to tolerate frost. This phenomenon was studied under controlled conditions in pea (Pisum sativum L.) in two Iines: Champagne, frost tolerant after cold acclimation and Terese, frost sensitive even if previously submitted to a cold acclimation period. Leaf, stem and root proteomes were analysed. Thirty five per cent of the identified differentially expressed proteins in leaves and stems during the cold acclimation period were involved in photosynthesis and glycolysis. ln stems, 25% were identified as folding proteins and ir roots, 47% were involved in the defense response. The raffinose, sucrose, glucose and citrate contents increased in Champagne leaves, stems and roots during the cold acclimation. ln contrast, the levels of these compounds were low in non-acclimated Champagne as weil as in Terese submitted to the cold acclimation period or not. Metabolite levels were also determined on the recombinant inbred lines (RIL) resulting from the cross between Champagne and Terese. Subsequent analyses permitted the detection of potential cold acclimation explicative OTL. ln particular, raffinose content QTL were colocalized with frost da mage QTL on the linkage groups 5 and 6. POL were also detected with the study of RtL leaf proteome. A number of these PQL colocalized with the previously detected QTL. The data obtained using these different approaches allowed us to propose hypothezises potentially explaining the mechanisms used by Champagne to tolerate frost
Durand, Rachel. "Valorisation d'hydrolysat de poisson pour la santé humaine : séparation des composés bioactifs par électrodialyse avec membranes d'ultrafiltration et évaluation de leurs activités biologiques impliquées dans le développement du syndrome métabolique." Doctoral thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/66672.
Fish by-product valorization is an economic and environmental issue. For several years, scientific researches have shown that fish by-products contained active molecules for human health, as polyunsaturated fatty acids and peptides. The aim of this thesis was to evaluate the potential use of herring milt hydrolysates for human health, especially by evaluating their potential actions in physiological parameters involved in the metabolic syndrome and the effect of their separation by electrodialysis with ultrafiltration membrane (EDUF) for the production of bioactive fractions. First, we have demonstrated that the supplementation of three different herring milt hydrolysates in a high fat high sucrose diet in mice was able to modulate some physiological functions involved in the metabolic syndrome: improvement of glucose tolerance, increase of the total energy intake and protection against the Lactobacillus disappearance in the gut microbiota. Moreover, the hydrolysates decreased the inflammation induction in macrophages stimulated with LPS at 1ng/ml and 100pg/ml. Secondly, we have evaluated the separation of two herring milt hydrolysates by EDUF: the first one was more complex with a mix of different molecules (lipids, nucleic acids and peptides) while the second one was mainly composed of peptides. A new configuration using four ultrafiltration membranes (two of 50kDa and two of 20kDa) allowed a simultaneous double separation of anionic and cationic compounds. It has been shown that only charged peptides and free amino acids were fractionated in EDUF, while the lipids and nucleic acids didn’t migrate to the recovery fractions. Moreover, the use of membranes with different cut-off allowed a separation of the hydrolysates in different molecular weight ranges. Indeed, the use of 20kDa membranes allowed the concentration of peptides with small molecular weights (<800Da) and free amino acids, while the recovery fractions obtained with the 50kDa membranes were composed oh peptide with higher molecular weights.Thirdly, the potential bioactivities of the recovery fractions and the herring milthydrolysates were evaluated in vitro. Hence, the separation of the first hydrolysate allowed the production of a final fraction increasing the glucose uptake and an antioxidant anionicfraction. While the separation of the second hydrolysate allowed the production of two antiinflammatory cationic fractions as well as the identification of two bioactive peptides sequences. All these results showed that milt herring hydrolysate contained bioactive compounds such as polyunsaturated fatty acids and peptides, improving some physiological functions involved in the MetS and may decrease its occurrence. More over, the separation of the hydrolysates by EDUF allowed the production of bioactive fractions and the identification of two new anti-inflammatory peptide sequences. This work demonstrated the existence of a beneficial effect of herring milt hydrolysate and its fractions for the human health, allowing a better valorization of this by-product of the food industry for the health sector.
Guerdam, Embarek. "Isolement d'une protéine possédant une activité lipoxygénase et acides gras lyase à partir d'une variété de pois protéagineux." Limoges, 1993. http://www.theses.fr/1993LIMO301A.
Silvestre, Marialice Pinto Coelho. "Nouvelles méthodes d'étude de la composition d'hydrolysats de caséine (cuprimétrie, spectrophotométrie, chromatographie d'exclusion stérique) : application à l'estimation de leur teneur en di- et tripeptides." Paris 11, 1993. http://www.theses.fr/1993PA114820.
Groleau, Paule Émilie. "Étude des interactions peptide-peptide dans un mélange de peptides issu d'un hydrolysat trypsique de ¿-lactoglobuline et de leur influence sur le fractionnement par nanofiltration." Doctoral thesis, Université Laval, 2003. http://hdl.handle.net/20.500.11794/17853.
Whey protein enzymatic hydrolysates contain several functional and bioactive peptides which justify their fractionatation to isolate such interesting molecules. Membrane separation technologies have an excellent potential for peptide separation but peptide-peptide interactions seem to reduce their efficiency. The objectives of this study were to demonstrate the occurrence of peptide-peptide interactions in a tryptic hydrolysate of β-LG, to identify the optimal physico-chemical conditions and peptides responsible of such interactions, as well as to evaluate the influence of such interactions on the fractionation of this hydrolysate by nanofiltration. Isoelectric focusing was used to fractionate the hydrolysate and to demonstrate a peptidic aggregation phenomena at acidic pH. Turbidimetry was then used to highlight the solubility of the hydrolysate according to the pH and some physico-chemical conditions. Peptide aggregates formed at pH 4 were centrifuged and separated, and peptides responsible for this aggregation were identified. From these peptides, the presence of chymotryptic peptides has justified a study of the impact of residual chymotryptic activity in the tryptic preparation on the aggregation phenomena. The second part of this work allowed the evaluation of the effect of these aggregates on the fractionation of the tryptic hydrolysate of β-LG by nanofiltration. It was shown that peptide-peptide interactions do not impair the fractionation. On the contrary, these interactions taking place in the polarized layer may have a positive impact on the fractionation.
Randriamahatody, Zo. "Valorisation biotechnologique des co-produits de crevette : utilisation de la protéolyse enzymatique pour des applications avicoles à Madagascar." Lorient, 2011. http://www.theses.fr/2011LORIS220.
Marine by-products represent valuable biological resources able to generate molecules with biological and nutritional interests. The objective of the present study is to investigate nutritional potentials of hydrolysates from fished and farmed shrimp heads from Madagascar. Thus, 4 enzymes operational at extreme pH conditions were screened: Pepsin, Novozym 37020, Protex 6L and Delvolase. Pepsine was the most efficient enzyme conducing to the production of small-sized peptides with molecular weight inferior to 1 000 Da and the amelioration of amino acids profile, promoting the nutritional quality. Then, peptic hydrolysis was optimized by using different pH conditions and different enzyme inactivations. Introduction of resulting hydrolysates into traditional malagasy poultry feeding ameliorated the production, with weight gains 2,3 times higher. Some hydrolysates presented also growth inhibition activity again fishes pathogenic and food microorganisms. Two hours peptic hydrolysis at maintained pH seemed to be the most efficient condition in the 2 fields studied. It was also the most effective for chitin extraction by producing the poorest mineral and protein containing exoskeleton resides. Those results suggest the efficiency of enzymatic hydrolysis of shrimp heads from Madagascar to ameliorate their nutritional quality, while allowing partially chitin extraction
Farges-Haddani, Bérangère. "Les peptides de colza : une alternative aux protéines animales dans les procédés de culture de cellules de mammifères ?" Vandoeuvre-les-Nancy, INPL, 2005. http://docnum.univ-lorraine.fr/public/INPL_T_2005_FARGES_HADDANI_B.pdf.
In order to improve the performances of animal cell culture processes for the production of therapeutic proteins, and to limit the risks of contamination by animal derived molecules, the effects of a supplementation of serum-free and animal-protein free culture media with rapeseed peptidic fractions were performed. Peptide fractions of various compositions were generated by enzymatic hydrolysis on proteic extract and membrane fractionation. These fractions, rich in nitrogen matter, displayed a variable effect on CHO cells, with a strong cell growth promoting effect of a fraction containing peptides with a broad range of size. In fact, this fraction increased the cell growth, prolonged cell survival, increased the specific production of the recombinant protein, and reduced the whole metabolism of carbohydrates. We also showed that tis peptidic fraction was utilized as nutritioinal additives, but also, as survival and/or growth promoting factors. Other additional advantages ot these peptides were highlighted, such as : an easier adaptation of various cell lines to serum-free conditions, a good cryoprotection of cells during the freezing process au good filterability. Indeed, a very simple culture medium was designed, completely free from animal molecules, and stimulating the growth of adherent or suspension cells from different industrial strains, for various culture scales. These results taken together suggest the use of this new particularly interesting peptidic source as an additive in animal cell culture processes
Tauzin, Jérôme. "Biofonctionnalités de peptides issus de caséines αs bovines : Cinétique d'hydrolyse trypsique de la caséine αs2 et activité inhibitrice de l'ECA des peptides". Nancy 1, 2003. http://www.theses.fr/2003NAN10224.
αS2-Casein is the less studied substrate to obtain bioactive peptides among the major milk proteins. After its purification by ion exchange chromatography followed by hydrophobic interactions chromatography, it was hydrolysed by trypsin and resulting peptides were identified. Their release kinetics revealed three areas having different susceptibility to proteolysis. These data and secondary structure prediction helped to define a hypothetical model of protein organisation in solution. Four tryptic peptides inhibited angiotensin-I converting enzyme (CEI) with IC50 values comprised between 4 and 15 micro M. Their sequences were confronted with others inhibitors to discuss sequence-activity relationships
El, youssef Cynthia. "Sensory benefits provided by selected microorganisms for the fermentation of plant matrices." Electronic Thesis or Diss., université Paris-Saclay, 2020. http://www.theses.fr/2020UPASB027.
The new food trend in favor of the increasing consumption of plant proteins is mainly linked to the negative effects of products of animal origin on health and environment. To meet consumers’ needs, agro-food industries are working on the development of plant protein-based products.Among the different sources of proteins, pea (Pitsum sativum) offers environmental, technological and nutritional advantages. However, its use in the formulation of products remains strongly hampered by the presence of off-flavors, described mainly as “beany”, “green” and “vegetable”. Fermentation is one of the means that could be chosen to modify the quality of these products.Therefore, this research consisted of studying the impact of fermentation on the sensory perception of a pea protein yoghurt-like product. Microbiological, physico-chemical and sensory methods were implemented.The molecules responsible for off flavors in the unfermented matrix were identified by gas chromatography coupled with mass spectrometry. Aldehydes, particularly hexanal, furans, alcohols and ketones are the major molecules present in this initial matrix.A variety of preselected microorganisms were cultured on this matrix, and their acidification and aromatization capacities were evaluated. Consortia of lactic acid bacteria and yeasts were selected, based on the desired functionalities that each provides.The modification of the sensory perception of fermented products was confirmed by sensory analyses. The origin of this improvement might be related to the production of fruity aromas by the yeasts and / or the degradation of off-flavors.In order to get a better understanding of this phenomenon, sensory analyses on model solutions of the targeted molecules (recombination and omission experiments) were performed.In parallel, molecular fingerprinting by gas chromatography coupled with olfactometry were carried out on the fermented products.Hence, the produced esters by yeasts played a decisive role in improving the sensory perception of pea protein fermented products. Regarding the molecules responsible for defects, the dominant impact of certain molecules including hexanal and 2-pentylfuran has been highlighted. Nevertheless, the effect of other off-flavor molecules, remaining in the fermented matrix, still needs further exploration. In particular, the perception threshold in these matrices needs to be determined and the interaction effects require exploration.To conclude, this industrial thesis allowed to file a patent pertaining to the development of an innovative ingredient, resulting from the combination of a fermentation process and stabilization by drying
Suwal, Shyam, and Shyam Suwal. "Fractionation of Peptides from Protein Hydrolysate by Electrodialysis with Filtration Membrane : process optimization, Fouling characterization and Control mechanisms." Doctoral thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26619.
Des peptides bioactifs ont déjà été fractionnés par électrodialyse avec membrane de filtration (ÉDMF) à partir d’hydrolysats de sous-produits de crabe des neiges. L’optimisation des paramètres apparaît maintenant indispensable pour perfectionner le procédé. Ainsi, le taux de migration des peptides, leur sélectivité et l'évolution des paramètres électrodialytiques ont été étudiés pour différents paramètres (configuration, concentration en KCl et types de champ électrique). La configuration (2) de la cellule d’ÉDMF comprenant deux compartiments d'alimentation et un compartiment de récupération a démontré des valeurs de champ électrique local relativement stables par rapport à la configuration (1) constituée d’un compartiment d’alimentation et de deux compartiments de récupération. Des peptides contenant des glutamates, des aspartates, et des glycines ont été séparés avec la configuration 1 et des peptides composés d’arginines et de lysines avec la configuration 2. Un taux de migration peptidique de 13,76 ± 3,64 g/m2h a été obtenu par le maintien constant de la conductivité des solutions. La sélectivité a été accrue en augmentant la concentration en KCl de 1 à 5 g/L dans le compartiment de récupération. Une augmentation de la force ionique a amplifié la charge de surface, agrandissant ainsi la taille effective des pores et réduisant la couche d'hydratation de la membrane d’ultrafiltration. Toutefois, les membranes échangeuses d’anions et de cations ont été colmatées par des peptides et des acides aminés et détériorées pendant l’ÉDMF. Pour résoudre ces problèmes, l’effet de l’application du champ électrique pulsé (PEF) et de l'inversion de polarité (PR) a été étudié. Le taux de migration des peptides n'a pas été affecté sauf avec PR à 40 V. La sélectivité a été maximale avec PEF à 20 V. La dissociation de l'eau a été réduite tout en conservant les propriétés physico-chimiques des membranes grâce à l’application du PEF et de la PR par rapport au courant continu (DC). En outre, la plus faible quantité d'énergie a été consommée avec le PEF. Par conséquent, il a été possible d’optimiser la technologie d’ÉDMF du point de vue de l’efficacité énergétique, de la sélectivité peptidique et de l’encrassement membranaire grâce à l’application du PEF et tout en maintenant la conductivité électrique des solutions.
Bioactive peptides were efficiently separated by using electrodialysis with filtration membrane (EDFM) from snow crab byproduct hydrolysate. Meanwhile, optimization of parameters is indispensable for scaling-up. The peptide migration rate and selectivity as well as evolution of electrodialytic parameters were studied with different parameters such as EDFM cell configuration, KCl concentration and type of electric field. The EDFM stack with two feed and one recovery compartments (configuration 2) has relatively stable electric field strengths (local) than the configuration with one feed and two recovery compartments (configuration 1). Peptides containing anionic amino acids: glutamic and aspartic acid as well as glycine and cationic amino acids: arginine and lysine were fractionated using configuration 1 and 2, respectively. Maintenance of solution conductivity upheld the local electric field and peptide migration throughout the treatment resulting in a higher peptide migration rate of 13.76±3.64 g/m2.h never observed so far. The selectivity of cationic peptides containing arginine and lysine increased significantly with increase in KCl concentration from 1 to 5 g/L. An increase in ionic strength amplified the surface charge density of filtration membrane subsequently increasing effective pore size and reducing hydration layer. However, both anion- and cation-exchange membranes were fouled by peptides and amino acids and were deteriorated during EDFM treatment. To address these problems, the effect of applying pulsed electric field (PEF) and polarity reversal (PR) was studied. The peptide migration rate was unaffected among PEF, PR and DC modes except with PR at 40 V. The selectivity of cationic peptides was maximum with PEF at 20 V. Fouling and water dissociation were significantly reduced and physicochemical properties of IEMs were better-protected with PEF and PR than DC. Moreover, the least amount of energy was consumed with PEF mode. Therefore, the parameters affecting EDFM process were optimized in terms of energy efficiency, selectivity and lower deterioration of membranes by applying PEF regime with configuration 2 and maintaining the constant electrical conductivity of solutions.
Bioactive peptides were efficiently separated by using electrodialysis with filtration membrane (EDFM) from snow crab byproduct hydrolysate. Meanwhile, optimization of parameters is indispensable for scaling-up. The peptide migration rate and selectivity as well as evolution of electrodialytic parameters were studied with different parameters such as EDFM cell configuration, KCl concentration and type of electric field. The EDFM stack with two feed and one recovery compartments (configuration 2) has relatively stable electric field strengths (local) than the configuration with one feed and two recovery compartments (configuration 1). Peptides containing anionic amino acids: glutamic and aspartic acid as well as glycine and cationic amino acids: arginine and lysine were fractionated using configuration 1 and 2, respectively. Maintenance of solution conductivity upheld the local electric field and peptide migration throughout the treatment resulting in a higher peptide migration rate of 13.76±3.64 g/m2.h never observed so far. The selectivity of cationic peptides containing arginine and lysine increased significantly with increase in KCl concentration from 1 to 5 g/L. An increase in ionic strength amplified the surface charge density of filtration membrane subsequently increasing effective pore size and reducing hydration layer. However, both anion- and cation-exchange membranes were fouled by peptides and amino acids and were deteriorated during EDFM treatment. To address these problems, the effect of applying pulsed electric field (PEF) and polarity reversal (PR) was studied. The peptide migration rate was unaffected among PEF, PR and DC modes except with PR at 40 V. The selectivity of cationic peptides was maximum with PEF at 20 V. Fouling and water dissociation were significantly reduced and physicochemical properties of IEMs were better-protected with PEF and PR than DC. Moreover, the least amount of energy was consumed with PEF mode. Therefore, the parameters affecting EDFM process were optimized in terms of energy efficiency, selectivity and lower deterioration of membranes by applying PEF regime with configuration 2 and maintaining the constant electrical conductivity of solutions.
Demers, Mathieu Véronique. "Activité antimicrobienne d'un extrait peptidique issus d'un hydrolysat trypsique de protéines de lactosérum." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28671/28671.pdf.
Kapel, Romain. "Amélioration d'un procédé de production d'un concentré de protéines blanches de luzerne semi-industriel et valorisation du concentré protéique dans le domaine des adhésifs et des nutraceutiques." Lille 1, 2005. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2005/50376-2005-186.pdf.
Linder, Michel. "Optimisation d'un procédé de valorisation de coproduits d'abattage par hydrolyse enzymatique : propriétés fonctionnelles et nutritionnelles des hydrolysats." Vandoeuvre-les-Nancy, INPL, 1996. http://docnum.univ-lorraine.fr/public/INPL_T_1996_LINDER_M.pdf.
Koumfieg, Noudou Victoire Yolande. "Impact de la concentration en peptides d'un hydrolysat de crabe des neiges sur leur séparation et leur sélectivité en cours d'electrodyalyse avec membrane d'ultrafiltration (EDUF)." Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27613.
The importance of functional and nutraceutical products has grown tremendously due to their added value. Their production requires the isolation and concentration of compounds, such as amino acids and bioactive peptides from protein hydrolysates. Therefore, a new separation technique EDUF (electrodialysis with ultrafiltration) was used. To optimize the process, important parameters such as electric field strength, membrane material and molecular weight cut-off, pH, ionic strength and flow rate of the solutions as well as cell configuration have already been studied, except for the initial peptide concentration in the feed solution. The objective of this study was to determine the impact of peptides concentration of snow crab by-product hydrolysate on selectivity and separation rate of anionic and cationic peptides, and on their antimicrobial activity. To assess the impact of peptides concentration, four values of protein concentrations (0.5%; 1%; 2% and 4%) were studied with other parameters (pH, conductivity, potential difference) of the system kept constant. The results showed that increasing the peptides concentration has an effect on separation rate of the peptides. The highest rate was observed at 4% with 291.9 mg/mL and 431.87 mg/mL peptide concentration, respectively for the anionic and cationic compartment. Other results also showed that increasing the initial concentration has no effect on selectivity. The migration rate increased linearly with increasing feed solution concentration while the relative energy consumption decreased with increasing feed solution concentration. The highest migration rates of 16.2 g/m2.h and 7.8 g/m2.h for the cationic and anionic compartments respectively were observed at 4%, with relative energy consumption of 3.53 Wh/g. However, increasing the concentration had no effect on the fouling and membrane integrity. In terms of antimicrobial activity, different fractions (anionic and cationic) and the initial hydrolysate were tested and did not showed antimicrobial activity on Micrococcus luteus.
Perreault, Véronique. "Prétraitement d'un isolat de protéines de lin par haute pression hydrostatique : impacts sur la structure protéique, l'hydrolyse enzymatique et les capacités antioxydantes des hydrolysats finaux." Master's thesis, Université Laval, 2016. http://hdl.handle.net/20.500.11794/26804.
Flaxseed is an oilseed widely cultivated in Canada. However, residues generated after oil extraction contains large amount of proteins and then can be much-valued in human diet due to its bioactive peptide fractions. The influence of high hydrostatic pressure (HHP) on flaxseed protein isolate was studied especially in terms of protein structures, enzymatic hydrolysis and final hydrolysate antioxidant activity. Flaxseed protein solutions (1% w/v) were subjected first to 600 MPa HHP treatments during 5 and 20 minutes at 20°C and were compared to non-pressurized samples. Two subsequent hydrolysis treatments were performed on pressure or non-pressure treated samples: tryptic hydrolysis was carried out and another hydrolysis was performed using pronase on tryptic hydrolysates. Firstly, the characterization of treated and untreated flaxseed protein isolates was done by spectrofluorometric and particle size analyses. Thereafter, flaxseed hydrolysates were analyzed by HPLC-MS and antioxidant capacity by ORAC. These results demonstrated that the pressurizing level and duration had an impact on proteins structure, inducing the dissociation of protein leading subsequently to aggregates. These aggregates were formed by decompression or during further storage. After enzymatic hydrolysis of pressurized or non-pressurized samples by trypsin and trypsin-pronase, chromatographic analyses showed that HHP treatments modified the concentration of certain peptides of the tryptic hydrolysates only. Finally, HHP increases antioxidant capacity (ORAC) of final trysin-pronase hydrolysates when compared to a control.
Roblet, Cyril Roland. "Fractionnement d'un hydrolysat de protéines de soya : Comparaison des technologies baro-membranaire (UF) et électro-membranaire (ÉDUF) pour la collecte de fractions bioactives." Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/29016/29016.pdf.
Samra, Assem. "Recherche de protéines reliées a la symbiose endomycorhizienne chez des pois (Pisum sativum L. ) compatibles (myc#+) et résistant (myc#-) et cinétique d'induction des endomycorhizines." Dijon, 1996. http://www.theses.fr/1996DIJOS064.
Henaux, Loïc. "Fractionnement d’un hydrolysat de protéines de saumon par électrodialyse avec empilement de membranes d’ultrafiltration afin de concentrer, isoler et identifier des peptides glucorégulateurs." Doctoral thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/66671.
Type 2 diabetes (T2DM) is a complex multifactorial disorder of glucose homeostasis. This disease has a genetic basis but is mainly caused by socio-environmental behaviours, such as overeating and a lack of physical activity. Despite dietary measures and medical treatments used to prevent and treat the disease, T2D continues to progress. The identification and production of bioactive peptides from natural sources offer an interesting alternative to synthetic drugs, whose concerns about side effects are constantly increasing. Thus, because of their abundance and richness in bioactive molecules, fish processing co-products offer an almost inexhaustible source of bioactive peptides. Indeed, in previous studies, cod and salmon proteins have been shown to improve cardio-metabolic health in in vivo studies, and to improve muscle glucose uptake, decrease hepatic glucose production, and inflammation. In addition, with a growing number of people to feed, the processing industry is at its height, and waste continues to accumulate. Nevertheless, in order to exert their bioactive effect, it is necessary to release these bioactive peptides from native proteins. Subsequently, one or more separation, using for example electrodialysis with ultrafiltration membranes, are needed to concentrate these peptides and generate bioactive fractions. Indeed, it was previously demonstrated the effectiveness of electrodialysis with ultrafiltration membranes to generate bioactive fractions, from complex matrices, able to improve the glucose uptake in vitro, from soy and salmon protein hydrolysates. In this context, the main objective of this thesis was to concentrate and identify bioactive peptides, by fractionating a protein hydrolysate from a salmon co-product, by electrodialysis with ultrafiltration membranes, and to study the impact of these fractions and peptides on T2D. In the first study, results demonstrated that a triple size selective separation by EDUF allowed to generate peptide fractions with different physicochemical properties (charge and mass). Moreover, it was demonstrated that such a separation allowed to modulate the in vitro response of the fractions for glucose metabolism. Indeed, from a single EDUF separation, cationic peptides with higher molecular weights were concentrated and demonstrated to enhance their glucose uptake capacity. Whereas, cationic peptides with lower molecular weights have decreased the glucose uptake capacity. In addition, analyses by mass spectrometry of the vi fractions allowed to characterize (retention time and charge) 17 cationic peptides and 21 anionic peptides, potentially responsible for the bioactive effect of the fractions. In a second study, a second EDUF fractionation, using as feed solution the final fractions recovered during the previous separation was performed. The selectivity of the process was confirmed by liquid chromatography-mass spectrometry analyses. Moreover, in vitro study of the bioactivities (glucose uptake, hepatic glucose production and inflammation) effect of these fractions, led to the identification of two very promising fractions, demonstrating a simultaneous effect on all three bioactivities tested. In addition, the tandem mass spectrometry analysis of these fractions allowed the sequence identification of 24 anionic peptides, potentially responsible for these bioactive effects. Finally, in a third study, based on the analysis of the spectra obtained by tandem mass spectrometry, 13 peptides were selected and synthesized, then individually tested for their ability to increase glucose uptake in muscle cells, to reduce glucose production by hepatic cells, and to decrease the inflammatory response of macrophages. Thus, for the first time, four new peptides identified from salmon by-products, demonstrated in vitro glucoregulatory properties.
Kobbi, Sabrine. "Purification de la RuBisCO à partir de la Luzerne, hydrolyse enzymatique, identification, structure-fonction des peptides bioactifs et leur valorisation dans des produits alimentaires." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10201.
Alfalfa is an excellent source of protein. However, RuBisCO proteins showed most interest. Indeed, this protein has been labelled the most abundant on earth; it constitutes about 65% (w/w) of soluble leaf protein of Alfalfa. In this work, a new method was introduced for the purification of RuBisCO from alfalfa powder 10% (w /v), using two different solvents and pH effect. In a first step, the performance of the proposed RuBisCO recovery method was evaluated through qualitative and quantitative analysis and the results obtained showed that this new method could replace some conventional industrial processes. In a second step, enzymatic hydrolysis was carried out on the purified RuBisCO, which resulted in a large bioactive peptide population. The final peptides after 24h of hydrolysis showed better antibacterial or antioxidant activity compared to the other peptide hydrolysates. Nine new antibacterial peptides have been identified and characterized by MS and have a MIC of 2-6 mM against four species of bacteria: B subtilis, E coli, L innocua and M luteus. In addition, antioxidants peptide fractions were identified in this work, their antioxidant activity was evaluated by various in vitro and in vivo tests on oil of Colza. Finally, the addition of peptide RDRFL derived from the peptic hydrolysis of RuBisCO has a positive effect on the prolongation of the shelf life of minced meat and of tomato puree
Leke, Lokombé. "Valorisation d'un hydrolysat de protéine obtenu à partir de l'hémoglobine bovine : Etudes expérimentales, immunochimiques et essais cliniques." Compiègne, 1994. http://www.theses.fr/1994COMP775S.
The aim of the present study was to evaluate the biological value and the nutritive efficiency of a peptic haemoglobin hydrolyse produced at a pilot –plant scale. The analysis revealed a deficiency in isoleucine and cysteine demanding an enrichment before utilisation, a ratio of essential amino acids : total nitrogen of 3,16 (amount of essential amino acids mg/g protein 49,7 %) and less than 1 % of free amino acids. Mass Spectrometry estimated the mass molecular of peptides between 600 – 1650 dalton. The evaluation of immunogenicity and antigenicity of native haemoglobin and its hydrolysate was done by ELISA and inhibition ELISA in mice : enzymatic hydrolysis seems to decrease or destroy the immogenic and antigenic activities of haemoglobin. The true digestibility and the protein efficiency studied in rats showed similar values as those observed with casein hydrolysate. Feeding of the premature child with breast milk enriched by haemoglobin hydrolysate allow to maintain an adequate growth and a better nitrogen tetention
Raveschot, Cyril. "Recherche d’ingrédients actifs, issus de Lactobacilles, utilisables pour la prévention de l’ostéoporose." Thesis, Lille, 2018. http://www.theses.fr/2018LIL1R064.
Lactobacilli are bacteria of major interest for health applications. These species are able to produce different active biomolecules by fermentation or exert a probiotic action. Thus, Lactobacilli represent a source of different ingredients which could be used for various health purposes. The objective of the present research is to study the potential of different lactobacilli to be use as ingredients dedicated to osteoporosis prevention. This work is based on a collection of 170 Lactobacillus strains isolated from dairy products in Mongolia. Two different strategies were undertaken: the use of lactobacilli as probiotics or the production of bioactive peptides by fermentation of milk proteins. A screening based on some probiotic characteristics allowed to select Lactobacillus strains which were studied for their capacity to modulate the intestinal calcium absorption. In the same way, screenings were used to select strains with important proteolytic abilities. Particularly, an original screening strategy, based on a multiparametric analysis of proteolysis occurring in milk was developed in this study. Milk protein hydrolysates were produced using the selected strains by batch fermentation of milk in bioreactor. The resulting products were then studied for different biological activity linked to bone health like angiotensin-converting enzyme inhibition or modulation of intestinal calcium absorption. By these results, an integrated continuous process, using a membrane bioreactor, was developed to produce an active ingredient by fermentation. This work highlights the potential health applications of some lactobacilli
Leconte, Danielle. "Contribution à l'étude de la valorisation du cruor des abattoirs : application de l'ultrafiltration à la préparation d'hydrolysats peptidiques à partir de l'hémoglobine bovine." Compiègne, 1989. http://www.theses.fr/1989COMPD159.
Ligné, Thierry. "Production par voie enzymatique et caractérisation d'oligopeptides : application à l'hydrolyse de protéines végétales pour l'obtention d'un produit d'intérêt nutritionnel pour l'alimentation animale." Compiègne, 1998. http://www.theses.fr/1998COMP1119.
Bodin, Alice. "Stratégie de modélisation et d’optimisation des performances de l’ultrafiltration pour le fractionnement d’hydrolysats protéiques." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0298/document.
Protein hydrolysates are high added value mixtures for various industrial areas, thanks to their nutritive, functional or nutraceutical properties. To enhance hydrolysates performances, fractionation processes such as ultrafiltration are used. However, the lack of tools to predict ultrafiltration performances is a major bottleneck for a rational implementation of the process. This research thesis work enables to validate a prediction strategy based on classical characteristics of hydrolysates and an experimental calibration of the membrane. Yields and enrichment factors in targeted peptides or fractions during ultrafiltration as well as the productivity of the process can be predicted. This global methodology of performances prediction is then used to optimize the implementation modes of ultrafiltration. The multiobjective optimization approach consists in maximizing the enrichment in targeted peptides or fractions while water consumption and / or process duration is minimized
Sylla, Khalifa Serigne Babacar. "Valorisation de co-produits de la sole tropicale (Cynoglossus senegalensis) par hydrolyse enzymatique : application en nutrition animale." Lorient, 2011. http://www.theses.fr/2011LORIS242.
This scope of work relates to the valorization of the tongue sole (Cynoglossus senegalensis) by-products resulting from the processing chain in Senegal by the implementation of enzymatic hydrolysis in order to obtain high value proteins. The by-products (viscera and heads) of tongue sole, were hydrolized with a large spectra protease (Protamex®). It appears that the hydrolysis degree (DH) was influenced by the temperature of the proteolysis. Indeed a DH=19% is obtained at 50°C while it reaches up to 25% at 40°C after 3 hours of enzymatic action. Resulting hydrolysates appears to be rich in protein (up to 61%° with around 10% of minerals. The study of the molecular distribution size of the peptides reveals that they are below 1760Da. The effect of the water proportion to conduce hydrolsis was studied. It appears that 50% of water is enough in our conditions to solubilize of four different water ratio to hydrolyze sole by-products by using Protamex® were compared. It was found t60% of the initial proteins. Resulting hydrolysates have a great nutritional value for seting up table fowls because they have in big quantity nine essential amino acids for the animal feed. Feed trials were then carried out on 1200 chickens (cobb 500) with 14 days of age. The results showed that high nutritional value by-products proteins increase the growth of the birds. Indeed, the live weights at 6 weeks are 2369. 60 G (batch 1), 2189. 60 G (batch 2), 2298. 05 G (batch 3) against 2158. 20 G (witness batch), with respective average GMQ of 78. 20 G, 66. 72 G, 69. 89 G and 68. 30 G. The carcass weights are 2112. 43 G (batch 1), 1994. 67 G (batch 2), 2081. 75 G (batch 3) and 1989. 22 G (witness batch). Food consumption seems little influenced by the level and the nature of proteins. However, their presence decreased the consumption index during the end of the study; it is 2. 30 (batch 1), 2. 07 (batch 2), 2. 05 (batch 3) and 20. 8 (witness batch). To identify the future application of hydrolysates in human food, a preliminary sensory analysis was carried out. The sensory profile was established with a jury of 14 expert judges. 11 profiles were found by this panel. In addition, the aromatic characterization revealed that 57 molecules are responsible for these odours described in sensory analysis. The description of these aromatic compounds opens potential way of valorization of these hydrolysates in human consumption
Monceaux, Philippe. "Valorisation des productions amylacées en Picardie : étude d'un nouveau procédé de fractionnement du blé tendre." Compiègne, 1986. http://www.theses.fr/1986COMPD252.