Dissertations / Theses on the topic 'Tournesol – Teneur en protéines'
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Albe, Slabi Sara. "Développement et optimisation d'un procédé extrapolable de production d'isolats de protéines de tournesol." Electronic Thesis or Diss., Université de Lorraine, 2019. http://www.theses.fr/2019LORR0167.
Sunflower meal, by-produced after oil extraction process, is a valuable source of proteins (30−70% on dry matter basis). These proteins are composed of two main fractions: globulins (helianthinins) and albumins (SFA). Thanks to well-balanced amino acid composition and good functional properties, they are considered very promising for human nutrition as protein isolates. However, the literature shows many scientific drawbacks during sunflower protein extraction and purification. These drawbacks lie on interaction between proteins and chlorogenic acid (major hydrosoluble phenolic compound of sunflower), poor extraction yield and helianthinin denaturation during protein purification by acidic precipitation. The goal of this thesis work was to overcome these limitations and to propose a scalable process for production of sunflower protein isolates. The first part of the thesis was based on the development of a new method for simultaneous quantification of proteins, free chlorogenic acid isomers and chlorogenic acid bound to proteins. This analytical tool provided fast and reliable access to performance criteria crucial for further development and optimization of sunflower protein production process. In the second part of the thesis, an optimal condition for extraction of total proteins from sunflower meal allowing maximizing extraction yield and minimizing protein-phenol interaction was searched. For this purpose, multicriteria optimization based on modelling by design of experiments and genetico-evolutionary algorithms was applied. Then, an alternative method for protein purification by ultrafiltration was developed. This part of study has improved the global understanding of sunflower protein extraction process and yielded in a satisfactory product. However, the residual meal produced after protein extraction was poor in proteins and rich in phytic acid (antinutritional factor). The third part of the thesis was therefore focused on the implementation of an alternative strategy of selective extraction of albumins. To do so, the methodology of modelling and multicriteria optimization, used in second part of the thesis, allowed to identify the optimal conditions for selective extraction of albumins with good yield keeping a satisfactory value of the residual meal. The extracted albumins were light-coloured, rich in sulphur-containing amino acids and more soluble than total sunflower proteins. The functional properties of albumins (foaming, emulsifying) were improved or comparable to those of soy proteins. Therefore, the established strategy provided a sustainable process for production of albumins that would be used in human nutrition and residual meal for feed applications
Raymond, Jacques. "Les protéines de la graine de Tournesol : fractionnement et composition : technologie d'obtention d'isolats et étude de quelques propriétés fonctionnelles." Bordeaux 1, 1986. http://www.theses.fr/1986BOR10582.
Zitouni, Nedjma Baya. "Caractérisation des protéines allergéniques de la graine et de l'huile de tournesol (Helianthus annuus) : contribution à l'étude des modifications des propriétés immunochimiques des protéines par les produits d'oxydation de l'acide chlorogénique." Vandoeuvre-les-Nancy, INPL, 2000. http://www.theses.fr/2000INPL024N.
Orliac, Olivier. "Valorisation des protéines de tournesol : étude de leur comportement thermique, rhéologique et de leur réactivité chimique, application à la fabrication de nouveaux matériaux biodégradables." Toulouse, INPT, 2002. http://www.theses.fr/2002INPT029G.
Ayhllon-Meixueiro, Fabiola. "Films biodégradables à base de protéines de tournesol : mise au point et étude des propriétés." Toulouse, INPT, 2000. http://www.theses.fr/2000INPT008C.
Leyris, Juliette. "Valorisation du tourteau de tournesol : étude, procédé et modélisation de l'extraction des protéines-exploitation de leurs propriétés fonctionnelles en vue de l'obtention d'agromatériaux." Toulouse, INPT, 1998. http://www.theses.fr/1998INPT017C.
Lagravere, Thierry. "Déterminisme agro-physiologique de l'expression de la trés haute teneur en acide oléique dans l'huile de tournesol (Helianthus annuus L. )." Toulouse, INPT, 1999. http://www.theses.fr/1999INPT011C.
Dimitrova, Tatiana. "Emulsions stabilisées par les protéines : forces colloi͏̈dales, rhéologie et crémage." Bordeaux 1, 2000. http://www.theses.fr/2000BOR12223.
Lacombe, Séverine. "Caractérisation génétique et moléculaire de la haute teneur en acide oléique dans les graines de tournesol (Helianthus Annuus L. ) dérivant du mutant pervenets." Montpellier, ENSA, 2001. http://www.theses.fr/2001ENSA0020.
Kibinza, Serge Landry. "Influence de la teneur en eau sur les processus d'altération associés au vieillissement des semences de tournesol ( Helianthus Annuus L. )." Paris 6, 2007. http://www.theses.fr/2007PA066153.
Suc, Sylvie. "Amélioration génétique de la teneur en protéines du soja (Glycine max L. Merr. )." Toulouse, INPT, 1993. http://www.theses.fr/1993INPT027A.
Villière, Angélique. "Approche physico-chimique et sensorielle de l'oxydation des lipides dans des émulsions stabilisées par des protéines." Nantes, 2005. http://www.theses.fr/2005NANT2042.
In many foods, lipids are present as small droplets dispersed in an aqueous matrix. This dispersion favors oxidation of unsaturated fatty acids which leads to a degradation of sensory and nutritional qualities of food. This work was aimed to clear up, in sunflower oil-in-water emulsions, the influence of oil-water-interface on lipid oxidation and on formation of volatile compounds, and to evaluate the sensory impact of these compounds. Analysis of oxidation kinetics, results demonstrate the key roles of metal location, emulsifying protein, and pH, on initiation of oxidation and on the proportions of the 19 identified and quantified volatile compounds. Many of these compounds have an odor activity leading to early detection of a “rancid” odor. This odor changes with time as relative quantity of volatile compounds do
Bordel, Anne-Claire. "Les protéines à domaines LIM chez le protoplaste de tournesol (Helianthus annuus L.) : expression des gènes et cytolocalisation." Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2000. http://tel.archives-ouvertes.fr/tel-00012190.
Nous avons étudié l'expression des gènes LIM précédemment décrits chez le tournesol dans les protoplastes par RT-PCR. Nous avons détecté un transcrit pour le gène HaWLIM-1, mais pas pour les deux autres gènes HaPLIM-1 et HaPLIM-2. Des anticorps polyclonaux spécifiques de la protéine HaWLIM-1 reconnaissent en immunoblot deux polypeptides distincts, dont les masses moléculaires sont respectivement de 52 kDa et 78 kDa. Ces masses moléculaires sont nettement supérieures à la taille attendue pour la protéine HaWLIM-1. Ces résultats indiquent que la protéine n'est pas présente sous forme de monomères dans les protoplastes, mais qu'elle participe à la formation de complexes protéiques stables.
L'étude par immunocytologie de la localisation intracellulaire de la protéine HaWLIM-1 révèle que cette protéine est présente simultanément dans deux compartiments distincts : le noyau et le cytoplasme. Dans le noyau, elle s'accumule préférentiellement dans le nucléole, et pourrait jouer un rôle dans la régulation de la transcription des gènes des ARNr, ou dans l'assemblage des ribosomes. Dans le cytoplasme, différentes approches, incluant des expériences de double-marquage et de déstructuration de composants du cytosquelette, ont permis de mettre en évidence une très forte colocalisation de la protéine HaWLIM-1 avec les microtubules, ce qui suggère un rôle pour cette protéine dans l'organisation du cytosquelette.
Lors de la culture des protoplastes, le gène HaWLIM-1 s'exprime constamment, avec cependant des variations dans le niveau d'expression. Des expériences d'immunoblot utilisant les anticorps spécifiques de la protéine HaWLIM-1 indiquent que de nouveaux polypeptides, de masses moléculaires égales à 35 kDa, 42 kDa et 64 kDa, apparaissent au cours de la culture. Cette observation suggère que la protéine HaWLIM-1 possède la capacité de s'associer et de se dissocier avec de nouveaux complexes protéiques au cours du développement. La protéine HaWLIM-1 est associée aux microtubules pendant tous les stades de la division : elle est présente au niveau de la bande préprophasique à la fin de l'interphase, au niveau du fuseau mitotique pendant la mitose, et au niveau du phragmoplaste pendant la cytokinèse. Ces observations semblent indiquer que la protéine HaWLIM-1 occupe une fonction importante au niveau des microtubules.
Piva, Guillaume. "Maîtrise de la qualité biochimique de la graine pour deux légumineuses : soja, haricot : impact des conditions de culture et des choix de génotypiques." Toulouse, INPT, 2001. http://www.theses.fr/2001INPT005A.
Lacaze, Xavier. "Interprétation des interactions génotype x environnement et étude des Déterminants génétiques de l'adaptation : exemple de la teneur en protéines du grain de blé dur (Triticum turgidum)." École nationale supérieure agronomique (Montpellier), 2005. http://www.theses.fr/2005ENSA0019.
Hernandez-Sanchez, Fabiola. "Contribution à l'étude du séchage de la spiruline et de son impact sur la qualité biochimique du produit sec." Lyon 1, 2006. http://www.theses.fr/2006LYO10313.
Spirulina is a high nutritive foodstuff which contains 55% to 65% of proteins. The quality of the dry product depends on drying methods. Thus, in this work, the convective drying method was investigated as concern process parameters influence and the influence of several drying methods on the biochemical quality of dried product. An air-lift photobioreactor of 40 L volume was built in order to obtain an important production of fresh biomass for the drying experiments. It was possible characterize its productivity and the spirulina cultures growth rate. The shrinkage behaviour of the biomass with convective drying was characterized for the initial samples shaped as cylinders and thin layers. The drying rate was corrected by taking of account the shrinkage. This revealed the existence of a constant drying rate periods for cylinders of various initial diameters. The Characteristic Drying Curve (CDC) and the values of the water mean diffusion coefficient were estimated for the cylinders. The proteins and total sugars contents on dried samples were analyzed after different drying methods by convective, infra-red, atomization, and freeze-drying. The best drying method for the recovery of proteins and total sugars contents was freeze-drying
Kossinova, Olga. "Insights into the selenocysteine incorporation mechanism in mammals." Strasbourg, 2011. http://www.theses.fr/2011STRA6221.
The amino acid selenocysteine is encoded by a UGA triplet which acts generally as a stop codon. A specialized machinery is used to incorporate this amino acid into selenoproteins, involving a specific stem-loop, termed SelenoCysteine Insertion Sequence (SECIS), and some protein factors. One of those is the SECIS Binding Protein 2 (SBP2), which is necessary for ribosome recognition of the UGA as the Sec codon. Using synthetic selenocysteine mRNAs and translational inhibitors, several steps of mRNA translation were analyzed. The data obtained allowed us to propose the following mechanism for selenocysteine insertion : during the transpeptidation step of elongation, SBP2 is bound to the ribosome; however, after transpeptidation, SBP2 leaves the ribosome and binds the SECIS in the pre-translocation step. We showed earlier that SBP2 binds specifically to the purified human 60S but not to the 40S ribosome subunits but the actual location was unknown. The SBP2•40S, SBP2•60S and SBP2•80S complexes were thus studied using crosslinking reagents. SBP2 did not crosslink to the 40S subunit in either the 40S•SBP2 or 80S•SBP2 complexes, correlating with the binding data. However, SBP2 crosslinks to the 60S subunit in either the free state or in the 80S ribosome. I next showed that the 28S rRNA contributes more to the crosslink than ribosomal proteins. This led us to use hydroxyl radical footprinting to study the molecular environment of SBP2 on the ribosome. According to the probing data, the binding of SBP2 to the human 60S subunit protects 2 helices in expansion segment 7 of the 28S rRNA. I proposed that the SBP2 binding site is located in the vicinity of the L7/L12 stalk
Khaldi, Marwa. "Étude du lien entre la physico-chimie de dérivés laitiers et leur aptitude à l’encrassement lors du traitement thermomécanique en échangeur de chaleur." Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10032/document.
This Ph.D. work is a contribution for understanding the fouling in plate heat exchangers (PHE) during the heat treatment of whey protein solutions. This work aims at establishing the relationship between the composition of the different whey protein solutions (β-lactoglobulin content (β-lg) and calcium), their denaturation behaviour and their ability to foul the hot surfaces of the PHE.This study showed the strong impact of the calcium content and the calcium/protein molar ratio on the β-lg thermal denaturation mechanisms, the distributions of the deposit fouling, deposit formation dynamics and the structure of the first deposit layers.The determination of the β-lg denaturation kinetic constants and the knowledge of the thermal profile allowed to simulate the concentration profiles of the different β-lg species (native, unfolded and aggregated) along the PHE and to study the correlation between the dry deposit mass of and the amount of denatured β-lg in the PHE. This simulation highlighted the negligible role of the aggregates in the fouling mechanisms and both the influence of the unfolded species and the calcium content on the distribution of protein deposition. Finally, a new correlation between the distribution of dry deposit masses in each channel of the PHE and the denaturation kinetic parameters was determined for each studied protein solution, showing thus that chemical reaction engineering approaches are requested for predicting proteinaceous fouling
Ayerdi, Gotor Alicia. "Etude des variations des teneurs et de la variabilité des compositions en tocophérols et en phytostérols dans les akènes et l'huile de tournesol (Helianthus annuus L. )." Phd thesis, Toulouse, INPT, 2008. http://oatao.univ-toulouse.fr/7788/1/ayerdi_gotor.pdf.
Boutouili, Ghania. "Variations de la composition protéique et minérale du lait de vache : incidences sur les intéractions minéraux-protéines et la valeur technologique." Vandoeuvre-les-Nancy, INPL, 1991. http://www.theses.fr/1991INPLA003.
Schweizer, Martin. "Fractionnement et identification de petits peptides issus de l'hydrolyse enzymatique des protéines de colza." Vandoeuvre-les-Nancy, INPL, 2002. http://www.theses.fr/2002INPL016N.
Cormeau, Jordan. "Recherche des partenaires protéiques et étude fonctionnelle de la région cytoplasmique des protéines BP-80 chez arabidopsis thaliana et helianthus annus." Toulouse 3, 2003. http://www.theses.fr/2003TOU30028.
Campanacci, Valérie. "Etudes fonctionnelles et structurales de protéines d'insectes impliquées dans le transport de phéromones ou de chémo-effecteurs." Aix-Marseille 1, 2001. http://www.theses.fr/2001AIX11023.
Moras, Benjamin. "Fractionnement de protéines végétales pour le développement d'ingrédients alimentaires infantiles hypoallergéniques et à teneur réduite en phytoestrogènes." Thesis, Toulouse, INPT, 2015. http://www.theses.fr/2015INPT0070.
The objectives of these works were to develop industrial processes for the production of four infant food ingredients with hypoallergenic properties and reduced levels of phytoestrogens. For this purpose, the nutritional properties of the rice and soy protein are promising. However, due to the presence of phytoestrogens (isoflavones) the consumption of soy protein isolates is a big concern for infant food security because the high exposure to these compounds, known to be endocrine disruptors. Consequently, it was first intended to develop a soy protein isolate with reduced content of isoflavones below 50 μg/g following the recommendations of French and European health authorities. Rice protein isolates are either non-existent on the market, or extremely rare. Therefore, the development of rice protein isolate with a minimum content of 90 % protein was another objective. For the sensitive population, such as infants, the aim of this work was also to develop soy and rice protein hydrolysates conferring hypoallergenic properties. To achieve this goal, the reduction of the size of proteins and the control of their molecular weight was studied. Two methods were used to achieve high extractions yields. A study of ethanol extraction ranging from small-scale optimization to industrial scale was used for a final product with a residual content in isoflavones below 50 μg/g. The second method was to retain isoflavones on adsorption resin from a soy protein hydrolysate. This was possible without preliminary extraction step by solvent. This method was also tested in the industrial scale. The chromatographic behavior of different isoflavones was also studied. The extraction of isoflavones with subcritical water and supercritical CO2 is also presented in this thesis even though these methods were not retained. These pressurized extractions showed the influence of the polarity of isoflavones and the protein content of soy products onto the isoflavone extraction. These works also identified a novel process for the production of rice protein isolate by the hydrolysis of polysaccharides with cellulolytic enzymes and amylases from concentrated protein byproducts from the glucose syrup industry. Studies on less processed materials such as rice bran and flour were also studied for protein isolation. The study of the hydrolysis by proteases of soy and rice proteins were monitored by various indicators such as pH, protein solubility, the degree of hydrolysis, the molecular weight profile by electrophoresis, and size exclusion chromatography. These processes are enabled for the production of four new ingredients that will be tested for their hypoallergenic characteristics before a large scale production
Colin-Schoellen, Odile. "Taux protéique et qualité fromagère des laits : maîtrise des facteurs de production." Vandoeuvre-les-Nancy, INPL, 1990. http://docnum.univ-lorraine.fr/public/INPL_T_1990_COLIN_O.pdf.
Le, Floc'h Nathalie. "Régulation nutritionnelle de l'oxydation de la thréonine chez le porc." Aix-Marseille 3, 1995. http://www.theses.fr/1996AIX30028.
Gavazzi-April, Camile. "Effet du mode opératoire sur l'efficience d'un procédé d'ultrafiltration pour la fabrication d'un concentré à haute teneur en protéines." Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/29956.
High-milk protein concentrates (over 80% total protein on a dry weight basis) are typically produced by ultrafiltration (UF) with constant-volume diafiltration (DF). Polymeric spiral-wound UF membranes with a molecular weight cut-off (MWCO) of 10 kDa are mostly used at commercial scale in order to maximize protein retention. Flux decline and membrane fouling during UF have been studied extensively and the selection of an optimal UF-DF sequence is expected to have a considerable impact on both the process efficiency and the generated volumes of by-products. The objective of this work was to characterize performances of UF-DF process in terms of permeate flux decline, fouling resistance, energy and water consumption and retentate composition as a function of MWCO (10 and 50 kDa) and UF-DF sequence (3.5X – 2 diavolumes (DV) and 5X – 0.8DV). UF-DF experiments were performed on pasteurized skim milk by means of a pilot-scale filtration system operated at 50°C and under a constant transmembrane pressure (TMP) of 465 kPa. Results showed that MWCO had no impact (p>0.05) on permeate flux for a same UF-DF sequence. However, permeate flux values were significantly higher during DF for the 3.5X – 2DV sequence whatever MWCO (p<0.05). Experimental values were used as part of a simulation for the production of high milk protein concentrates in a model dairy plant processing 1500 m3 of skim milk in 20 hours. This work revealed that despite the severe total flux decline occurring during high solid concentration of milk (89% for the 5X – 0.8DV sequence vs. 58% for the 3.5X – 2DV sequence), reducing the DF step could still be of great interest in terms of energy and water consumption. The results generated by this project will benefit dairy processors producing high-milk protein concentrates with regards with their technological choices in a sustainable development perspective.
Diafiltration
Lecourieux, David. "Analyse fonctionnelle des variations de la concentration en calcium libre dans le cytoplasme et le noyau des cellules de tabac en réponse à des éliciteurs des réactions de défense : identification de protéines kinases cibles." Dijon, 2001. http://www.theses.fr/2001DIJOS062.
Kuate, Kamga Blaise. "Caractérisation et formulation de nouveaux ingrédients alimentaires à base de complexes de protéines végétales et de polysaccharides." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/37917.
The objective of this work was to characterize the physicochemical properties of complexes formed of plant proteins and dietary fibers. Nine complexes were produced from three plant protein isolates (two soy isolates and one pea isolate) and two fibers (corn and beet) with protein-polysaccharide (P-PS) ratios 1-1, 2-1 and 4-1 by gradual addition of hydrochloric acid up to a pH of 4. The size, the charge and water and oil absorption capacities of these complexes were evaluated with the aim of developing new ingredients with desired functionalities. The formation of complexes allowed to create a synergistic effect on the water absorption capacity of these new ingredients, which was found to be higher for the complexes based on soybeans and beet fiber (20 and 26% for Soya1-Bet and Soya2-Bet against 9 and 23% for Soya1-Corn and Soya2-Corn). The increase in water absorption was generally lower than oil absorption by more than 35%. The great synergy between the P-PS complex was correlated with a low protein content and smaller complex sizes. The formation of complexes appears as an interesting way to modulate the functionality of proteins and fibers to improve the level of fortification of foods.
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.
Bedie, Kouadio Gerard. "Microencapsulation de composés nutraceutiques dans des complexes protéines-polysaccharides." Doctoral thesis, Université Laval, 2008. http://hdl.handle.net/20.500.11794/19823.
Dulau, Laurent. "Recherche sur les protéines responsables de la casse protéique des vins blancs secs : approche biochimique et génétique." Bordeaux 2, 1990. http://www.theses.fr/1990BOR20110.
Pascal, Marie-France. "Étude de critères morphophysiologiques en vue de création variétale, chez l'orge Hordeum vulgare L." Toulouse, INPT, 1985. http://www.theses.fr/1985INPT008A.
Bon, Nina. "Etude du rôle des protéines PiT1/Slc20a1 et PiT2/Slc20a2 dans la détection du phosphate extracellulaire dans le squelette des mammifères." Thesis, Nantes, 2017. http://www.theses.fr/2017NANT1034/document.
Phosphate (Pi) is a vital ion involved in numerous biological processes. Prolonged deficiency of Pi results in hypophosphatemia leading to serious consequences, including impaired bone mineralization. On the other hand, hyperphosphatemia can lead to life-threatening situations such as vascular calcifications. Controlling serum Pi concentration is therefore critical to life quality and expectancy. The first necessary step of this control is the ability to detect changes in extracellular Pi levels, which implies the existence of a Pi-sensing mechanism that would inform the body or the individual cell. Contrary to yeasts and bacteria for which Pi membrane transporters play a key role in Pi signaling, the underlying mechanism in mammals remains unknown. In this work, we hypothesized that the high affinity Na-Pi cotransporters PiT1/Slc20a1 and PiT2/Slc20a2 could be involved in Pi-sensing in mammals. As a first step, we showed in vitro that deleting either PiT1 or PiT2 blunted the Pi-dependent activation of MAPK/ERK1-2 both in osteoblasts and chondrocytes. This suggested that both PiTs were necessary to Pi signaling. Using a BRET approach, we then demonstrated that PiT1 and PiT2 could form a hetero-dimeric complex that was modulated by variations of extracellular Pi, but not by Pi transport across the membrane. Using PiT2 knockout mice, we showed that PiT2 was also necessary for the Pi-dependent regulation of FGF23 secretion, the main hormone responsible for Pi homeostasis. Taken together, our data propose that the PiT proteins could play a pivotal role in the Pi-sensing mechanism in mammals, which may be uncoupled from their Pi transport function
Alary, Rémi. "Isolement, caractérisation et importance technologique de deux gluténines de faible poids moléculaire chez le blé dur." Montpellier 2, 1988. http://www.theses.fr/1988MON20010.
Chbab, Najat. "Réplication et morphogenèse du virus MDV-1 : caractérisation d'une protéine de tégument produit du gène UL17 essentiel à la réplication virale." Tours, 2006. http://www.theses.fr/2006TOUR4004.
This work aimed at studying the Marek's Disease virus (MDV) UL17 protein which is homologous to the capsid and tegument protein of HSV-1 virus. For this purpose, we used a bacterial artificial chromosome (BAC) of the highly pathogenic MDV strain RB-1b to generate mutant viruses in which the UL17 gene was either deleted or tagged with the HA peptide. The results showed that MDV pUL17 is a phosphoprotein (82 kDa) essential for viral replication. During the infection, pUL17 localizes in the nuclear compartment. This nuclear localization is not an intrinsic property of pUL17 and implies a viral factor. The co-localization of pUL17 with the major capsid protein VP5 and its influence on the cellular distribution of the tegument protein pUL14 favour the hypothesis that pUL17 participates in early tegumentation
Lavoignat, Mélanie. "Identification des facteurs génétiques et environnementaux impactant la qualité santé des protéines du grain de blé tendre." Electronic Thesis or Diss., Université Clermont Auvergne (2021-...), 2023. http://theses.bu.uca.fr/nondiff/2023UCFA0084_LAVOIGNAT.pdf.
Plant proteins quality is a major issue in the context of global changes and considering the need for a healthy, safe and sustainable diet. The wheat grain proteins provide almost 20 % of adult nitrogen intake. Their health quality notably relies on a high content of essential amino acids, the absence of precursors of harmful molecules such as acrylamide, and a more digestible gluten. Abiotic stresses due to climate change and changes in agronomic practices are environmental factors that impacts the protein and amino acid content and composition of grain, and therefore the health quality of proteins. Little is known about the influence of genetic and environmental factors and their interaction on the health quality of grain proteins. Therefore, the aim of this PhD is to quantify and characterize the genetic diversity of bread wheats grown under environmental constraints that are suitable to obtaining processed products with high protein digestibility and low acrylamide content. Based on a ‘field to fork' approach, the partial in vitro digestion of breads from 34 genotype-environment combinations were used to assess the influence of wheat grain phenotypic variations on the digestibility of bread proteins. This work revealed genotypic variability in the degree of protein hydrolysis, which would depend on the protein content and composition of the flour used for bread-making. However, there were no significant difference for bread protein partial digestibility between old and modern varieties. Peptidomic analysis of the gastric and jejunal compartments of the in vitro digestion model indicates that the abundance of the released peptides differs according to the genotypes and their growing environment. The concentration of free asparagine in the grain, a precursor to acrylamide formation, varies according to genotype and environment factors. It is controlled by several QTLs, but none of which is common to several environments. Ultimately, these results provide new insights into the genetic and environmental factors influencing the health quality of wheat grain proteins, towards selecting varieties with higher protein digestibility and lower acrylamide content
Alami, Younes. "Rôle d'une bactérie productrice d'exopolysaccharides (Rhizobium sp. ) dans l'agrégation du sol rhizosphérique du tournesol : conséquences de l'inoculation sur la structuration du sol et la nutrition minérale de la plante." Nancy 1, 1997. http://www.theses.fr/1997NAN10169.
The bacterial strain Y AS34, selected for exopolysaccharide (EPS) production, was isolated from the rhizoplane of sunflower (Helianthus annuus) in a Dystric Cambisol. From cartography and sequencing of the 16S rDNA gene it was concluded that strain Y AS34 belongs to the genus Rhizobium. The gelatinous EPS produced by this strain was different from succinoglycan usually produced by bacteria belonging to the genus Rhizobium. In the presence of 1 % (w/w) of the EPS purified from strain Y AS34, the water holding capacity of soil from St-Florent-sur-Cher was enhanced by 50%. Inoculation of sunflower seeds and soil with strain Y AS34 led to a significant increase of rootadhering soil mass per root biomass (+80%), under both, water stress and normal water supply conditions. Concomittantly with this bacterial effect on the mass of root-adhering soil, an increase of soil macro-porosity (pore diameter between 5 and 50 mm) was observed. In addition to these physical changes of root-adhering soil, nitrogen uptake by sunflower was significantly increased after inoculation with Rhizobium sp. Y AS34 in the presence of 1 N-nitrates. Strain y AS34 seems to modify the soil structure around the root system in a way that the water supply of sunflower and its nitrogen uptake is increased counteracting the effect of water deficit on sunflower growth
Ducruet, Julien. "Etude des protéines du vin rouge : Mécanismes d'action d'enzymes de macération sur le raisin rouge." Bordeaux 2, 2000. http://www.theses.fr/2000BOR20742.
Bogard, Matthieu. "Analyse génétique et écophysiologique de l'écart à la relation teneur en protéines - rendement en grains chez le blé tendre (Triticum aestivum L.)." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2011. http://tel.archives-ouvertes.fr/tel-00679581.
Bouvier, Nathalie. "Le soja : impact en nutrition et médecine humaine." Paris 5, 1998. http://www.theses.fr/1998PA05P145.
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.
Andrianasolo, Fety Nambinina. "Modélisation statistique et dynamique de la composition de la graine de tournesol (Helianthus annuus L.) sous l’influence de facteurs agronomiques et environnementaux." Thesis, Toulouse, INPT, 2014. http://www.theses.fr/2014INPT0100/document.
Considering the growing global demand for oil and protein, sunflower appears as a highly competitive crop, thanks to the diversification of its markets and environmental attractiveness and health. Yet the protein and oil contents are submitted to genotypic and environmental effects that make them fluctuating and hardly predictable. We argue that a better knowledge of most important effects and their interactions should permit to improve prediction. Two modeling approaches are proposed: statistical one, where we compared three types of statistical models with a simple existing one. The dynamic approach is based on source-sink relationships analysis (field and greenhouse experiments in 2011 and 2012) during grain filling. Performances of both modeling types and their validity domain are compared
Ilami, Golnar. "Purification, caractérisation structurale et fonctionnelle d'une protéine, BnD22, induite par la contrainte hydrique progressive chez le colza." Paris 12, 1996. http://www.theses.fr/1996PA120028.
Nesterenko, Alla. "Etude et fonctionnalisation de protéines végétales en vue de leur application en microencapsulation." Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0148/document.
Proteins extracted from vegetables are relatively low-cost, non-toxic, biocompatible and biodegradable raw materials. They represent a good alternative to animal-based proteins and petroleum-extracted polymers. In this study, proteins derived from soybean and sunflower seeds were used as wall materials for microencapsulation of hydrophobic (-tocopherol) or hydrophilic (ascorbic acid) active material by spray-drying technique. Soybean proteins are widely used in food and non-food applications, especially in microencapsulation. They were studied in this work as wall material of reference. Sunflower proteins are not actually used in industrial application, but only in the form of oil-cake for animal feeding. That’s why new ways of valorization of this agricultural by-product should be investigated. Several proteins’ modifications such as enzymatic hydrolysis, acylation, cross-linking and cationization were studied in order to improve encapsulating properties of wall material. In the context of green chemistry, all the modifications and preparations were performed without use of organic solvents and chemical catalysts. The effect of protein chemical and enzymatic modifications, and process parameters (homogenization pressure, wall/core ratio and protein concentration) on different characteristics of liquid preparations and microparticles (viscosity, emulsion droplet size, microparticle size and morphology) and on parameters related to the spray-drying process (yield and efficiency of microencapsulation) was particularly investigated in this study. The obtained results confirmed that sunflower proteins are quite suitable as encapsulating agent and provide the microencapsulation efficiencies significantly higher compared to those obtained with soy proteins
Vigeant, Nathalie. "Effets de la diminution de la teneur en protéines et de l'ajout d'additifs sur les propriétés de foisonnement de la crème à fouetter U.H.T." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ60660.pdf.
Basset, Gilles. "Etude du protéasome 20S dans des racines de mai͏̈s : relation entre carence carbonée, oxydation des protéines et protéasome." Bordeaux 2, 2000. http://www.theses.fr/2000BOR28778.
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
Laporte, Marie-Aline. "Contribution à la modélisation de l’absorption du cadmium par les racines du tournesol (Helianthus annuus L.) en relation avec l’architecture racinaire." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR15214/document.
Cadmium (Cd) is naturally occurring in soils that are also enriched by human activity. Cd contaminates food crops because of its absorption by plant roots. Because it is a toxic element for living organisms, its concentrations in food and feed plant products are subjected to regulatory limits. Therefore, it is necessary to understand the transfer of this metal from the soil to the edible plant part, especially for sunflower (Helianthus annuus L.), our model plant that can accumulate more Cd than other crop species. This study tested the hypothesis that the amount of Cd absorbed by sunflower was related to the root architecture. We characterized, at the individual roots level, a longitudinal variation of the influx of Cd2+ absorption in relation with the culture medium, the order and the age of roots. These variations were attributed to the development of apoplastic barriers (cellulose, lignin and suberin deposition) that restrict the absorption of Cd2+ into the cytosol. By simulation, it has been shown that these variations could theoritically impact the total absorption of Cd2+ in hydroponics depending on the root architecture while in solid substrate (sand) the impact was much more limited. Furthermore, a comparison of 14 sunflower cultivars showed that the variability in Cd concentrations in shoots was rather due to differences in absorption independent of root architecture and in variations in the root to shoot distribution. The longitudinal variation in the Cd root influx can then be considered of minor importance compared to the between cultivar variability in Cd uptake, the origin of which remains to be determined. In the perspective of modelling the total uptake of Cd in soil conditions, it could then be possible to assume a global mean influx of Cd independent of the root architecture
Rederstorff, Mathieu. "Etude du rôle du sélénium et de la sélénoprotéine N dans les pathologies musculaires." Université Louis Pasteur (Strasbourg) (1971-2008), 2006. https://publication-theses.unistra.fr/public/theses_doctorat/2006/REDERSTORFF_Mathieu_2006.pdf.