WorldCat Identities

Laboratoire de Chimie Agro-industrielle (Toulouse / 1995-....).

Overview
Works: 47 works in 47 publications in 2 languages and 48 library holdings
Roles: Other
Publication Timeline
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Most widely held works by Laboratoire de Chimie Agro-industrielle (Toulouse / 1995-....).
Système chimique délignifiant à base de peroxyde d'hydrogène by Nicoleta-Iioana Vladut( )

1 edition published in 2012 in French and held by 2 WorldCat member libraries worldwide

Résumé non communiqué par le doctorant
Incorporation and release of organic volatile compounds in a bio-based matrix by twin-screw extrusion by Natalia Castro Gutierrez( )

1 edition published in 2016 in English and held by 1 WorldCat member library worldwide

Nowadays, scientific and political communities are focused on ways to better preserve and manage the natural resources of our planet. In order to reduce consumption of fossil resources, and to develop more environmentally friendly industrial processes, the industry of flavors and fragrances became interested in developing new bio-based encapsulating materials. In the present work, maltodextrins have been chosen as main component of the matrix, and pea protein isolate and a modified starch were selected as compatibilizing additives. The incorporation of volatile odorant compounds and the elaboration of the new bio-based delivery systems were performed, all in one single step, by low temperature twin-screw extrusion. The physicochemical, thermal and morphological properties of these matrices were studied, as well as the encapsulation efficiency and the release profile of the active compounds. These investigations have led to a better understanding of the impact of the formulations and of the incorporation of the active compound on the process parameters. The interactions between the wall and the encapsulated materials were also analyzed. The characteristics of the new bio-based delivery systems and the established extrusion process conditions were found to be very promising to be employed in the field of perfumery
Study of the valorization of teak (Tectona grandis) by-product from a sawmill by a continuous process under subcritical water by Lucero Chavez Salgado( )

1 edition published in 2021 in English and held by 1 WorldCat member library worldwide

Tectona grandis L.f. (teck) est un bois tropical apprécié sur le marché du bois en raison de ses performances exceptionnelles et de sa valeur économique. Parmi ses principales qualités figurent la stabilité dimensionnelle et la résistance à la pourriture, toutes deux attribuées à ses matières extractibles. Ils contiennent des composés biologiquement actifs, principalement des quinones et des anthraquinones qui confèrent une résistance naturelle aux termites et aux champignons, ainsi qu'une activité antioxydante et pharmacologique. La demande mondiale de teck devrait continuer à augmenter, et avec elle les résidus à traiter. Le teck ayant des caractéristiques excellentes, les sous-produits des usines de transformation du bois pourraient constituer une bioressource potentielle de composés chimiques. La technologie d'extrusion bivis a été étudiée comme technique d'extraction solide/liquide de la sciure de teck. L'utilisation de l'eau comme solvant a été proposée, non seulement parce qu'il s'agit d'un solvant respectueux de l'environnement, mais aussi parce que les conditions de pression et de température appropriées peuvent être atteintes à l'intérieur de l'extrudeur, conduisant l'eau à des conditions sous-critiques. Différentes conditions de température et de rapport liquide/solide ont été évaluées selon un plan expérimental défini. Des métabolites secondaires avec un contenu phénolique total élevé ont été obtenus. La valorisation de l'extrudat comme matériau pour la préparation de biocomposites a également été étudiée
Emulsions de Pickering stabilisées par des particules de bois by Francisco Vasquez Velado( )

1 edition published in 2019 in French and held by 1 WorldCat member library worldwide

The valorization of biomass for high value-added applications is a real scientific, technological and environmental challenge. Valuing wood and stimulating its industrial use towards sustainable applications is a climatic issue: wood and the forest are carbon sinks. The native features of the wood give it hydrophilic and hydrophobic properties for interfacing and stabilizing emulsions. This research is therefore an answer to the question of substitution of surfactants from petrochemicals by natural, renewable and biodegradable materials. Multiparameter studies have made it possible to compare the emulsification and emulsion stabilization efficiency as a function of process (Ultra-Turrax UT technology, Ultra-Sound US technology) and formulation parameters. Stable emulsions are generated from energy expenditure that depends on the technology implemented (3000 kJ.L-1 for the US probe and 6000 kJ.L-1 for UT). In formulation, limits were determined, in particle concentration (0,31 g.L-1 to 2,37 g.L-1), in volume fraction of oil (0,1 to 0,6), in pH (3 to 9) and in salinity (< 2 g.L-1) to delimit zones of better stability of direct emulsions, useful for upscaling studies (> TRL 4). Pathways for modifying the surface properties of wood particles have been addressed to obtain inverse and multiple emulsions. Wood particles are new and powerful candidates for the stabilization of emulsion
Développement d'une méthode de couplage FFF multi-détection pour la caractérisation de la fraction macromoléculaire impliquée dans l'astringence des vins rouges by Kevin Pascotto( )

1 edition published in 2021 in French and held by 1 WorldCat member library worldwide

Red wine is a complex matrix containing macromolecules such as polyphenols and polysaccharides. These macromolecules and their interactions have an impact on taste properties such as astringency. Wine polyphenols include condensed tannins or proanthocyanidins extracted from the grapes but also many derivatives formed during winemaking and aging. Astringency results from tannin interactions with salivary proteins and increases with their concentration and molecular weight. In addition, polysaccharides (PS) have been shown to reduce the perception of astringency in wines, probably due to their interactions with polyphenols. Classically, the structure and average molecular weight of tannins are determined by HPLC after depolymerization. However, these methods are not appropriate for evolved tannins as found in wine and do not give access to molecular weight distribution. Steric exclusion chromatography techniques have been developed for determination of molecular weight distribution of polyphenols and PS but common protocols allow neither their simultaneous analysis nor detection of their complexes. The Asymmetrical Flow Field- Flow Fractionation (AsFlFFF) separates molecules according to their hydrodynamic radius as well as macromolecular complexes without degrading them. Its coupling with Multiple Angle Light Scattering (MALS) detection allows determination of the radius of gyration of molecules and, in combination with a differential refractorometer (dRI) of their molecular weight. Coupling with UV-visible spectrophotometry allows quantitative detection of phenolic compounds. This technique has already been used to characterize purified phenolic compounds or maromolecules in beer and white wine but has never been applied to red wine. The objective of this research was first to develop the analytical conditions to separate the macromolecules and red wine complexes in their native state and characterize them using a multiple detection system (UV-vis -MALS -dRI). A wine like solution was used as mobile phase to limit the degradation of the complexes present in red wine. our results show that the macromolecular fraction of wine analyzed by AsFlFFF represents only a few percent of the wine components that contribute to UV absorption. The AsFlFFF separation profile was divided into four fractions. Owing to the injection of tannin and PS extracts into the system and the analysis of fractions collected after analysis of different wines, the first three were attributed to tannins coeluted with lower molecular weight PS (F1), intermediate molecular weight PS (F2) and higher molecular weight PS (F3). In addition, the presence of UV-absorbing material in F2 and F3 fractions suggests the presence of proteins or of polyphenols interacting with these polysaccharides. The last fraction (F4) likely corresponds to very large objects but has not been characterized. This method was used to explore the relationships between AsFlFFF-UV-vis - MALS-dRI fractograms and the astringency scores of a series of red wines which were tasted by a sensory panel. This study showed that the most astringent wines are characterized by high concentrations of higher molecular weight polyphenols while the less astringent wines showed the highest PS contents in F2 and F3, confirming that the perceived astringency is counteracted by polysaccharidic material. These results also showed that the higher molecular weight PS are particularly associated with astringency softening. The variables related to F4 had no impact on red wine astringency
Huile native et huile traitée de Ricinodendron heudelotii : biodisponibilité, structure et réactivité chimio-enzymatique des acides gras linoléniques conjugués CLnA-(Alpha et béta) éléostéarique. by Diakaridja Nikiema( )

1 edition published in 2021 in French and held by 1 WorldCat member library worldwide

Deux méthodes de décorticage sont utilisées pour isoler les amandes des graines de Ricinodendron heudelotii. L'huile modifiée extraite de ces amandes obtenues par traitement thermique traditionnel et l'huile brute extraite des amandes par décorticage mécanique manuel ont des profils acides gras différents. Les résultats montrent que l'exposition des triglycérides de l'huile brute des amandes de ricinodendron heudelotii aux rayons ultraviolets ou au soleil entraîne l'isomérisation de l'acide -éléostéarique en acide -éléostéarique et en acide catalpique. Nous avons étudié les milieux réactionnels issus de la réactivité de deux types de CLnA-libre, CLnAlibre E (61%) et CLnA-libre E (42%) de l'huile brute et de l'huile modifiée par réaction d'estérification enzymatique directe avec le glycérol. Les réactions d'estérification réalisées dans des systèmes sans solvant organique en présence de la lipase Novozym 435 orientent la formation des esters partiels dans le sens de production des 1,3-diglycérides (un mélange monodi : 30-60). Cependant, l'utilisation du tert-butanol favorise l'accumulation des esters partiels plus hydrophiles, les 1-monoglycérides (un mélange mono-di : 61-30). L'étude des fractions monoglycérides et diglycérides des esters partiels montre qu'ils sont riches en CLnA avec des teneurs comprises entre 50 à 70%. L'étude de la réactivité des CLnA-libres E ( = ou ) et d'EPGCLnA E ( = ou ) sous azote ou sous l'oxygène de l'air pour la synthèse de polymères à 70 °C montre que seul les EPG-CLnA E polymérisent sous atmosphère inerte par une réaction de type Diels-Alder auto-initiée par le CLnA- . En présence de l'oxygène de l'air les CLnA-libres E ( = ou ) et EPG-CLnA E ( = ou ) polymérisent. Les substrats riches en -éléostéarique polymérisent vite avec un ordre partiel par rapport au CLnA de 1 et les substrats riches en - éléostéarique polymérisent lentement avec un ordre partiel par rapport au CLnA de 0. L'étude des acides gras dans les extractibles montrent que les acides oléique et linoléique ne polymérisent pas, ils jouent le rôle de fluidifiant facilitant la polymérisation. Les polymères obtenus sont un mélange de macromolécules composées de polymères à poids moléculaire de 1860 g/mol, de polymères à poids moléculaire compris entre 1860 à 25000 g/mol et des polymères de poids moléculaire supérieur à 25000 g/mol. Ces polymères ont en outre des Tg inférieures à -30°C sont souples et sous forme de gel à température ambiante
Development of analytical methods of multi-pesticide residues for controlling the tea quality, from tea plantation to consumer by Tuan kiet Ly( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

Tea is the second most-consumed beverage in the world, surpassed only by water, due to its health benefits. However, because of monoculture cultivation practices, the use of pesticides during tea cultivation is common. Over time, the number of pesticides used has increased, and, to protect consumers' health, many countries and regions have established maximum residue limits of pesticides for a variety of foods and beverages, including tea. For instance, the European Union (EU) has set the maximum residue limits (MRLs) for more than 480 pesticides and their metabolites in tea products. Therefore, the development of analytical methods for multi-pesticide residues in tea is a challenge, because tea is a complex commodity with many compounds that can interfere with results, such as polyphenols, pigments, and caffeine. The aim of this thesis is to develop rugged and robust methods with high sensitivity, accuracy, and precision to meet the EU regulations for simultaneous determination of 400 pesticide residues in tea products using ultra performance liquid and gas chromatographies coupled to tandem mass spectroscopy (UPLCMS/ MS and GC-MS/MS, respectively). The first part of thesis focused on elimination of matrix effects in green tealeaves by combining QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction and mixed-mode SPE (solid phase extraction) clean-up. A C18 SPE cartridge paired with SPE GCB/PSA proved to be the most effective clean-up method and enabled 225 pesticide residues to be quantified, based on solvent calibration curves (154 residues using UPLCMS/ MS and 71 residues using GC-MS/MS). The analytical methods were validated fully in accordance with the SANTE/11945/2015 (EU). LOQs for most pesticides (386/400 or 96.5%) were below 10 &#956;g/kg, i.e., less than the EU MRL (5-70 mg/kg). In the second part, matrix effects for 400 pesticide residues were investigated and improved for the analysis of different types of teas (white, green, oolong and black ones). Results showed that combining QuEChERS extraction and mixed-mode SPE clean-up, and following the reduction of the injection volume were found to be the most effective procedure to overcome matrix effects. More than 190 pesticides (> 95% of the 200 ones) had the matrix effect within the range of ± 20% for UPLC-MS/MS. Therefore, they can be quantified using solvent calibration curves. On the other hand, matrix-matched calibration curves should be used to overcome matrix effects for GC-MS/MS. Moreover, we recognized that matrix effects in GC-MS/MS were not only signal enhancement but also suppression. Finally, in the third part of this work, the established method was successfully applied to the determination of multi-pesticide residues in 106 tea samples. In total, 26 tea samples (24.5%) were containing at least one pesticide violation, with 43 pesticide residue violations. The most frequently detected pesticides were neonicotinoids, synthetic pyrethroids, and triazole fungicides. In terms of origin in this study, Taiwan had the most pesticide-contaminated samples with 83.3%, following by China (73.7%), Vietnam (64.7%), and India (Darjeeling) (55.0%). The results showed that samples exceeding EU MRLs regulations were still high with 24.5%. Therefore, assessments of multipesticide residues in tea need to be continued
Coupure de liaisons glycosidiques de la biomasse saccharifère couplée à la formation de liaisons esters amphiphiles by Sidrine Kerthy Koumba Ibinga( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

In 2030, vegetal-based chemistry will occupy 30% of total chemistry in France. Bioresources offer the opportunity to substitute products from petrochemicals. With a stable penetration rate of 25- 30% according to ADEME forecasts, biosurfactants are a way of adding value to agricultural products. The lipophilic and hydrophilic sources needed to obtain these amphiphilic compounds can be completely natural. Thus, the chia seed of the Oruro® variety has been used as a source of the hydrophilic part represented by the mucilage. The surface mucilage of the seed of this variety domesticated in France is made up of polysaccharides, proteins and minerals. It can be extracted effectively by ultrasonic cavitation in aqueous media. The composition and properties of the mucilage are related to the extraction time. This mucilage constitutes a hydrophilic source for obtaining amphiphilic esters. The lipophilic source chosen is the Irvingia gabonensis almond from a variety rich in high myristic (51%) and lauric (38%) butter. The triglycerides of this butter are made up of mixtures of saturated fatty acids. They are good candidates for food, nutrition and also industry and production of technofunctional biosurfactants. The work is therefore aimed at the simultaneous valorization of the mucilage and oil of I. gabonensis by the synthesis of biosurfactants. Two synthesis routes for obtaining amphiphilic esters have been explored. The first pathway involved the implementation of the transesterification reaction between glucose and methyl laurate in a deep eutectic medium DES Choline chloride/glucose. The second pathway involved acid catalysis in an organized medium by the implementation of the esterification reaction of glucose or mucilage with lauric C12:0 and myristic C14:0 fatty acids in the presence of dodecylbenzene sulfonic acid (DBSA). The studies of the esterification reactions were previously carried out using glucose and then transferred to mucilage. The use of DBSA with a dual role as a Brönsted catalyst and surfactant promotes the contact of the reagents, catalyzes the esterification reaction between the hydroxyl groups of glucose or polysaccharides and the carboxylic groups of the C12:0 lauric and C14:0 myristic fatty acids and therefore allows the glucose esters of degree of substitution DS=1-2 to be obtained. The surfaceactive and emulsifying properties of these glucose esters are comparable to those of a commercial Olivem 1000 ester, a mixture of sorbitan olivate and cetearyl olivate. The reaction between chia Oruro® mucilage and the fatty acid mixture of I. gabonensis in the presence of ADBS resulted in a profound structural modification of the biopolymer. Its lipophilization is obtained by the double monoacylation of the hydroxyl sites of the mucilage by the mixture of lauric C12:0 and myristic C14:0 fatty acids. The intrinsic viscosity of the acylated mucilage is very low (6.34 dL/g) compared to that of the crude mucilage (36.18 dL/g) used as starting reagent. This results in a profound change in the techno-functional properties of the acylated mucilage
Fractionnement par cristallisation extractive à froid des acides gras libres et des triglycérides de l'huile de Nephelium Lappaceum L. (Ramboutan) : oxygénation et enrichissement en acides gras particuliers by Gré Véronique Douniama-Lonn( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

In this study, the fruits of Nephelium Lappaceum L. (Rambutan) were harvested in Boko, in the southern area of the Republic of Congo. Oilseed plant with an oil-rich core (36 %), particularly composed of long chain fatty acids: C16:0 4.84 %, C18:0 5.48 %, C18:1 45.62 %, C18:2 2.70 %, C20:0 26.53 %, C20:1 9.27 % and C22:0 2.64 %. Rambutan oil was hydrolyzed enzymatically in the presence of lipase Candida rugosa, the free fatty acids are obtained with a ratio of saturated fatty acids (AGS)/monounsaturated (AGI) of 0.67. The availability of saturated and monounsaturated fatty acids of the C20 and C22 families stimulated our investigations towards the development of shortenings and biotensioactives with a high melting point. Two strategies have been implemented using free fatty acid concentrates derived from the enzymatic hydrolysis of rambutan oil in the presence of Candida rugosa lipase. The first was to achieve the cold crystallization of saturated fatty acids by gelation / defrosting technology. At the end of this process, a physical separation of the fatty acid mixture into two fractions is observed. A thermal study of the solid and fluid fractions was carried out and showed that the AGS (To = 15, 86 °C, Tf = 18.49 °C) cool faster, but melt slower than the AGI (To = -19 46 °C, mp = 3.87 °C). The contents go from 55.6% after hydrolysis to 63.53 % of AGI in the fluid fraction and 39.1 % after hydrolysis to 45.13 % of AGS. The results of the SFC indicate an AGS content of 25.98 % in the fluid fraction but of 38.24 % in the solid fraction ; And the mass yield of 16 % to 55 % and 84 % to 45 % respectively of the fluid fraction (enriched in AGI, in particular in MUFA) and the solid fraction (enriched with AGS). The second strategy was to perform the allyl insertion of singlet oxygen in long-chain monounsaturated free fatty acids C18:1 and C20:1, carried out in an emulsified medium consisting of a multiphase NaOH / H2O2/Na2MoO4 system. The reaction product, using GC, shows the presence of unconventional fatty acids, two isomers of respective fatty acid hydroperoxides of each trans-conforming MUFA (C18:1 and C20:1) and an increase in saturated fatty acids content with long chain C20:0 (26.21 % to 56.46 %) and C22:0 (2.48 % to 3.77 %). The product of this reaction has an AGS/AGT ratio of 0.82. The sequential evaluation of the fatty acids of the Ramboutan core oil makes it possible to propose two platforms of biomolecules shortenings with a high melting point: A platform with a well defined composition of saturated fatty acids C20:0 and C22:0 and another constituted by a bulk of C20:0-C22:0 saturated fatty acids and transmonohydroxyperoxide trans unsaturated fatty acids. Investigations on the hydroperoxidation of unsaturated fatty acids have revealed a particular interest on the impact of hydroxyperoxide radical on the movement of the trans and cis configuration in these fatty acids modified in the presence of glycidol in monoesters of glycerol and hydroxyperoxide fatty acids unsaturated cis. This is another novel synthesis platform of new cis-unsaturated hydroxyperoxyd biotensiatives offered by the sequenced recovery of unsaturated fatty acid concentrates from rambutan oil
Fractionnement des complexes lignine-polysaccharides issus de différentes biomasses lignocellulosiques par extrusion bi-vis et séparation chromatographique by Assad Mogni( )

1 edition published in 2015 in French and held by 1 WorldCat member library worldwide

The objective of this work is to validate a new way of valuing various agricultural and forestry coproducts. Study was devoted on the separation of lignin and hemicelluloses contained in extracts obtained by twin-screw extrusion. Twin-screw technology has been chosen to evaluate different extraction conditions. Trial conditions have been adopted in order to highlight the influence of mechanical, thermal and chemical effects on the extraction performances for various plant matrices. Efforts have been made to give priority to mild extraction conditions in the interest of preserving the integrity of the extracted polymers and limiting the environmental impact. Thus hydro-thermal extraction tests without chemical solvents were compared to more conventional alkaline extraction to evaluate their efficiency. This identified the most favorable extraction conditions according to the characteristics of each biomass. The extracts, with hemicelluloses and phenolic compounds, were purified with ion exchange and adsorption resins. Work focused on mechanisms fixations characterization with model solutions conditions containing one or several molecules. Kinetic and isotherm were determined for lignin, coumaric acid and ferulic acid. Then, results were compared to results obtained with the extracts. This study allowed to identify the mechanisms involved in the separation of the lignin-carbohydrates complex
Etude des interactions contenant-contenu appliquée aux matrices cosmétiques by Pauline Murat( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

The cosmetics market has been developing steadily for several years and represents several billion of euros by itself. Cosmetic products target the entire population, from babies to elderly persons. Cosmetics legislations, particularly those from the European Union, impose an innocuousness of these products for the health of all the consumers. Cosmetic products packagings must be safe for human health, in the same way as products they contain. Packagings roles are numerous. They must contain the product and ensure a protection against external aggressions (light, microbiological contaminations...). They also have to seduce the consumers and give them information on the product. Therefore, packaging development is an important step of a product creation, especially in the cosmetic industry. In the food and pharmaceutical industries, European legislation imposes tests on the packagings to prove their innocuousness. For cosmetic products, these tests are not mandatory and nevertheless necessary to ensure that the product is safe for human health, as required by the law. Container-content interactions are all the exchanges that exist between a product and its packaging. Among these interactions, leaching can be defined as the phenomenon of migration of compounds from primary packaging into the product. This migration can affect the quality and the efficiency of the product, but also theconsumers safety. European Union has published regulations to control these studies: the European Pharmacopoeia for pharmaceutical industry and regulation EC n°10/2011 on plastic materials and articles intended to come into contact with food for food industry. Cosmetic industry is also concerned via regulation EC n°1223/2009 on cosmetic products. However, unlike the two other legislations, this document does not contain numerical values about tolerated migration limits. Available information for the container-content interactions are list of prohibited and restricted substances (Annexes II and III, respectively) and Article 17 of the regulation EC n°1223/2009, which states that “The non-intended presence of a small quantity of a prohibited substance, stemming from impurities of natural or synthetic ingredients, the manufacturing process, storage, migration from packaging, which is technically unavoidable in good manufacturing practice, shall be permitted provided that such presence” does not affect human health. Due to the absence of threshold values and normalized protocols, container-content interactions studies are difficult in the cosmetic industry. They are nevertheless essential to ensure the consumer safety and the product conformity. In this context, this thesis aims to establish a strategy of container-content interactions applied to cosmetic products and consequently ensure the packagings safety. Based on the packaging portfolio of Pierre Fabre Dermo-Cosmétique, twelve representative packagings were selected. Then, based on the model of migration studies in the food industry, simulants were selected to mimic the behavior of cosmetic products. After contact with the packagings, simulants were analyzed by several analytical techniques in order to identify extractables. Meanwhile, physico-chemical characteristics of the packagings were determined and an extractables and leachables study present in the materials was led by thermal extraction techniques. A container-content study protocol applied to cosmetic matrices was developed on the model of food and pharmaceutical industries. This strategy, adapted to cosmetic products, allowed the safety evaluation linked to the packaging and the conclusion about extractables and leachables potential risks
Vers la synthèse verte d'un nouvel organocatalyseur tensioactif biosourcé : détermination de ses propriétés physico-chimiques by Clément Giry( )

1 edition published in 2019 in French and held by 1 WorldCat member library worldwide

The development of green chemistry around its twelve principles has changed the way chemists work. The use of water as solvent is evident as it is not toxic, cheap and widely available. However, it is not easy to carry out catalysed organic reactions in water. Indeed, most metalbased catalysts oxidize and become inactive in its presence. Organocatalysis has therefore aroused great interest because of the low toxicity of the employed catalysts as well as their resistance to water and oxidation. In this context, the imidazolidinones developed by D. MacMillan are organocatalysts that can be easily prepared and they can performed, through iminium ion activation, asymmetric catalysis by controlling the stereoselectivity of the reaction. Moreover, to achieve a maximum of organic reactions in water, the use of surfactants is essential. They allow the solubilisation of organic reactions in water through the formation of micelles in the core of which the reaction will occur. In order to use only one molecule, work have been done to graft to an organocatalyst to a long carbon chain, giving it surfactant properties. In this context, our study aims to synthesize a new surfactant organocatalyst on which is grafted an imidazolidinone at the end of the hydrophobic chain. The biosourced synthons of this molecule as well as the reaction conditions were chosen so as to respect as much as possible the principles of green chemistry. As the two first synthetic routes did not lead to the desired molecule, the starting synthons were changed, finally allowing the target molecule to be obtained in 10 steps. More than half of the steps have then been reviewed to improve their green aspect. The main improvement of these steps, and one of this thesis' innovations, was to reduce the use of compounds toxic for Human and/or environment via, in particular, the replacement of some solvents classified carcinogenic, mutagenic, reprotoxic (CMR) with a new one: 4-methyltetrahydropyran. For each step, the green metrics were calculated to justify if it was an improvement. Finally, once the targeted molecule obtained, its solubility in water was studied. Its surfactant character was then characterized in order to verify its activity on the surface tension at the water-air interface. The determination of the size of the aggregates formed in water as well as the molecular modeling completed the state of knowledge of the type of self-organized structures realized by this new molecule
Study of new exchangers for boron removal from water containing high concentration of boron by Thi Thu Hien Nguyen( )

1 edition published in 2017 in English and held by 1 WorldCat member library worldwide

Le bore est nécessaire pour le développement des plantes supérieures (structuration de la paroi végétale). Il pose cependant des problèmes (défoliation, pourriture et chute des fruits mûrs). Pour l'homme, sa toxicité se traduit par des nausées, des diarrhées, des troubles du développement intellectuel, neurologique et physique. La pénurie en eau douce conduit à dessaler l'eau de mer pour augmenter la quantité en eau destinée à la consommation humaine, l'industrie et l'agriculture. Lors de ce procédé, il faut éliminer les ions majeurs mais aussi le bore présent à des concentrations élevées (> 4,5 mg L-1, environ 0,45 mM). Son usage dans l'industrie et son rejet dans l'environnement conduisent à la pollution des eaux souterraines et de surface. Son élimination est donc indispensable, sachant que l'Organisation Mondiale de la Santé recommande une valeur guide de 0,5 mg L-1 dans l'eau potable et une valeur maximale de 0,3 mg L-1 dans l'eau utilisée pour l'irrigation. Cette thèse porte sur l'étude cinétique et thermodynamique des échanges du bore à la surface de différents matériaux en fonction de paramètres physico-chimiques (pH, concentration initiale ...) à l'aide d'essais en réacteurs fermés et en colonnes. Deux types de résines commerciales ont été choisies : (i) les résines échangeuses d'anions Ambersep 900-OH et Amberlite IRA 402 Cl avec des fonctions ammonium, (ii) les résines spécifiques Amberlite IRA 743 et Diaion CRB 03 ayant des fonctions méthylglucamine. Les premières essais en réacteurs fermés montrent que les échanges liquide-solide sont rapides avec une élimination du bore > 96 % pour t < 30 min pour Amberlite IRA 743, Diaion CRB 03 et Ambersep 900-OH. Pour t > 2 h, un équilibre est observé pour toutes les résines. Le modèle du pseudosecond ordre permet de décrire la cinétique de sorption pour les 4 résines. A l'équilibre, l'adsorption est maximum d'une part dans une gamme de pH compris entre 6 et 12 pour les 2 résines sélectives Amb IRA 743 et CRB 03, et d'autre part pour un pH de 8 pour la résine Ambersep 900-OH et un pH 10 pour la résine Amberlite IRA 402 Cl. A pH 8 et pour les concentrations en bore < 20 mM, la sorption du bore est représentée par le modèle de type Langmuir pour Amberlite IRA 743, Ambersep 900-OH et Diaion CRB 03. Par contre, la rétention du bore sur Amberlite IRA 402 Cl suit une isotherme de type linéaire. A pH 8 et pour des concentrations en bore < 20 mM, les capacités de sorption sont : 1, 0,7, 0,3 et 0,05 mmol g-1 pour Diaion CRB 03, Amberlite IRA 743, Ambersep 900-OH et Amberlite IRA 402 Cl, respectivement. Les résines Ambersep 900-OH, échangeuse d'anions, et Amberlite IRA 743, sélective, ont été utilisées pour les essais en colonnes en fonction de la concentration en bore et du temps de séjour. Pour la résine spécifique, le temps de séjour dans la colonne affecte fortement le comportement du bore : lorsqu'il diminue, son élution est rapide suivie d'une longue traînée ; lorsqu'il augmente, la courbe de percée correspond à un système à l'équilibre. Pour un temps de séjour élevé, les résultats confirment la non-linéarité observée lors des essais en réacteurs fermés. Pour la résine échangeuse d'anions, la non-linéarité est aussi confirmée. Ces essais permettent de différencier le comportement du bore lors de sa désorption. La régénération est obtenue après des traitements acides et basiques pour la résine spécifique alors qu'un traitement alcalin est suffisant pour la résine anionique. Une étude plus détaillée des mécanismes est en cours et permettra de les intégrer dans un même modèle. La fixation du bore sur des pectines et sa rétention par des membranes d'ultrafiltration (membranes de seuil de coupure différent) a aussi été étudiée. Les pectines ont été caractérisées (composition en sucre et en bore présent initialement) et la viscosité des solutions pectiques mesurée. Des essais de filtration ont permis de déterminer l'efficacité de production et de rétention du bore sur ces matériaux
Recherche de conditions de synthèses en flux continu et d'analyses rapides d'huile de tournesol ozonée pour la lutte antibactérienne contre les mammites by Julien Vinet( )

1 edition published in 2021 in French and held by 1 WorldCat member library worldwide

Ozonated vegetable oils have been studied for years for their antibacterial and antifungal properties. This bio-sourced product is the result of the reaction of ozone, a powerful oxidising gas, with a wide spectrum of vegetable oils. With a proven microbiological action on many bacterial strains and fungi, ozonated oils are a real natural alternative to the use of antibiotics for certain pathologies. It has been shown that the properties of the product obtained are linked to the reaction conditions and only batch synthesis is possible to date. Moreover, the analyses to characterise this product are long, tedious and require the use of a large quantity of dangerous chemicals. The aim of this work was to optimise the methods of synthesis and analysis of ozonated sunflower oil to efficiently produce a bioactive product capable of acting against a pathology of interest in agronomy: mastitis. Initially, ternary sunflower oil/water/nonanoic acid mixtures were studied. The addition of water and/or acid makes it possible to modify the physical properties of the mixture while maintaining or even improving its chemical properties. Fluid end products with chemical properties like pasty products as described in the literature could be synthesised. This low viscosity is an important physical characteristic which makes it possible to envisage an innovative synthesis in a microreactor. To date, this is the first proof of concept for the continuous flow ozonation of vegetable oil. Subsequently, an optimisation of the analysis methods was envisaged by looking for alternative characterisations. The linking of chemical analyses on ozonated oils with spectral measurements in the infrared range made it possible to establish prediction models. The reference methods for measuring the iodine and peroxide indices are long, costly, destructive, and consuming many chemicals. Infrared technology, after a specific calibration phase, allows the desired indices to be quickly quantified. It is even possible to consider using this methodology online at the output of a continuous flow synthesis or in a specially designed reactor in the laboratory, and thus obtain information on the chemical parameters of a mixture in real time. Finally, mastitis is an inflammation of the udder, most often in response to an invasion of bacterial origin, which affects the health of the animal and the quality of the milk. Ozonated sunflower oil has been shown to be useful in the fight against mastitis as an alternative to the overuse of antibiotics. More than a hundred bacterial strains isolated from reported cases of mastitis in sheep have been subjected to ozonated sunflower oil. The antibacterial effect of the product was measured, and the antibiotic resistance profiles of the strains were determined. The efficacy of the product was demonstrated against all strains including many multi-resistant strains. These results lead to the conclusion that the use of ozonated sunflower oil presents itself as an effective alternative to remedy the phenomenon of constantly evolving bacterial resistance. However, it would be interesting to validate these results on living organisms to evaluate the in-vivo efficiency of these ozonated oils
Optimisation de la pH-sensibilité de protéines végétales en vue d'améliorer leurs capacités d'encapsulation de principes actifs destinés à la voie orale by Maria Antonieta Anaya Castro( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

In the pharmaceutical field, the oral route remains the preferred route of administration because it is simpler and better accepted by patients. However, this mode of administration is problematic for many active pharmaceutical ingredients (API) with low solubility, low permeability and/or instability in the gastrointestinal environment. Their microencapsulation in polymeric matrices can make them able to respond to these factors, especially if the microparticles generated resist the environments encountered during the gastrointestinal tract and then play a protective role, both for the API and for the mucous membranes encountered. The search for new excipients, from agroresources such as natural polymers, is booming. Vegetable proteins, thanks to their functional properties such as good solubility, relatively low viscosity, and emulsifying and film-forming properties, are preferred candidates. In addition, the great diversity of their functional groups makes it possible to envisage various chemical or enzymatic modifications. The aim of this work was to study the interest of soy protein as a coating material for API intended for the oral route, and more particularly as a candidate for the development of gastro-resistant forms. A soy protein isolate (SPI) was used as a coating material and the atomization as a process. Ibuprofen, a nonsteroidal anti-inflammatory drug, was chosen as a model molecule because of its low solubility requiring an improvement in its bioavailability, and its gastric side effects requiring an enteric shaping. Two chemical modifications of proteins (acylation and succinylation) have been studied in order to modify the solubility of the soy protein. These modifications were carried out in accordance with the principles of Green Chemistry, especially in the absence of organic solvent. The microcapsules obtained by spray-drying were characterized in terms of rate and encapsulation efficiency, morphology and size distribution of the particles, physical state of the encapsulated API and capacity of release in simulated gastric and intestinal medium. The results obtained validated the interest of the chemical modifications of the soy protein to modulate the release kinetics of API. The chemical modifications appeared particularly suitable for the encapsulation of hydrophobic active ingredients, and allowed to obtain ibuprofen release kinetics decreased to acidic pH (gastric). The last part of this work allowed to validate this last hypothesis by the realization of gastro-resistant forms on the model of MUPS tablets (multiple unit pellet system). The results of this exploratory work demonstrate that soy protein, combined with a multiparticle shaping process coupled with direct compression, can be a biosourced, environmentally friendly alternative (aqueous solvent handling, drying and compression steps reduced) and confident to the coating used in traditional gastroresistant forms
Eco-compatible syntheses of bio-based solvents for the paint and coating industry by Nydia Ileana Guzman Barrera( )

1 edition published in 2018 in English and held by 1 WorldCat member library worldwide

Global solvent production accounts for about 28 million tonnes, including 5 million tonnes in Europe. The paint and coating industry is the main consumer (46% of the solvents produced). In this sector, the most used solvents are ethyl acetate, butyl acetate and methyl ethyl ketone. These molecules are currently synthesized industrially from petrochemical substrates in the presence of homogeneous catalysts and under energy-consuming conditions. In order to reduce the environmental impact of paints and coatings, the substitution of these fossil-based solvents by their bio-based equivalents has been studied in the framework of the European project ECOBIOFOR (FP7/2007-2013/Grant Agreement no 605215), in which this thesis work was inscribed. Thus, the objective of this thesis was to develop production processes for these three solvents that would start from renewable synthons and would be simple to implement, inexpensive and respectful of the principles of green chemistry. For the production of ethyl and butyl acetates, two synthetic routes have been studied in the presence of an ion exchange resin as a heterogeneous catalyst. The first route uses acetic acid and the corresponding bio-based alcohol (ethanol or butan-1-ol); the second involves acetic anhydride instead of acetic acid. Kinetic and thermodynamic studies have led to select the most efficient resin and the most suitable reaction conditions. This study has finally allowed to propose an efficient and innovative coproduction process for the two targeted acetates in which their purification is facilitated, the production of waste and co-products is reduced and the recycling of the resin is possible. The evaluation of the performance of the synthesized acetates in nitrocellulose lacquer and polyurethane varnish formulations has shown that these molecules meet the specifications in terms of drying, viscosity, film formation, gloss and adhesion. Finally, the environmental benefit of the co-production process was highlighted by the calculation of green metrics and the life cycle assessment (LCA) of the produced esters. Furthermore, the influence of the origin of alcohols (bio-based or petrochemical) on the environmental impact was evaluated. The impact on climate change is reduced through the use of bio-sourced synthons. For the synthesis of methyl ethyl ketone, we decided to study the decarboxylation reaction of levulinic acid, which is a bio-based platform molecule available and inexpensive. Unlike the main industrial process, which relies on the dehydrogenation of butan-2-ol from fossil origin, the method developed in this work uses conditions that are more respectful of the environment since the reaction is carried out in water in the presence of potassium persulfate and a silver salt at a moderate temperature (100°C). The evaluation of the role of each of the reagents allowed us to propose a complex reaction mechanism for this reaction. The study of the evolution of the solid phase species carried out through various spectroscopic analyzes (SSNMR, XRD, XPS, AES and SEM) made it possible to highlight the species involved in the decarboxylation and finally to propose a method to obtain high conversions and yields
Study of the integrated biorefinery of vegetable and essential oil in Apiaceae seeds by Evelien Uitterhaegen( )

1 edition published in 2018 in English and held by 1 WorldCat member library worldwide

Les fruits de coriandre ont été identifiés comme une source riche en huile végétale de haute qualité, à forte teneur en acide pétrosélinique et en huile essentielle. Un système d'extraction innovant a été conçu et développé en utilisant la technologie d'extrusion bi-vis. Il a permis l'obtention d'un produit nouveau, à savoir une huile végétale de coriandre aromatisée et à haute valeur ajoutée, d'un condensat présentant une concentration élevée en huile essentielle et d'un tourteau révélant une forte teneur en protéines. Le tourteau a montré son intérêt en tant que liant naturel pour la production de panneaux de fibres renouvelables issus de la paille de coriandre, un résidu de la culture de la plante, conduisant à des agromatériaux auto-liés et ayant un rapport performance/coût élevé. Les fibres de la paille de coriandre ont également présenté une bonne capacité de renforcement lorsqu'elles étaient utilisées comme charge naturelle dans des biocomposites thermoplastiques à base de polypropylène ou de biopolyéthylène, permettant le moulage par injection de matériaux peu couteux et aux propriétés mécaniques prometteuses. Ce travail présente ainsi une forte contribution à la mise en place d'une véritable bioraffinerie intégrée de la coriandre et à la démonstration de sa mise en oeuvre à une échelle industrielle
Paramètres de performances de photo-électrodes de Ti02/Kaolinite et d'électrolytes à base de carbonates biosourcés dans la cellule solaire sensibilisée par la bixine by Winda Rahmalia( )

1 edition published in 2016 in French and held by 1 WorldCat member library worldwide

The development of natural dye sensitizer for solar cell applications has attracted much attention because of its inherent advantages such as low cost, simple preparation, readily available resources, and low impact in the environment. However, the main problems related to dye-sensitized solar cell (DCCS) are low photostability and low efficiency. In this thesis, the bixin extracted from annatto (Bixa orellana L.) seeds was used as sensitizer. To improve its stability and the performance of the DSSC, the use of activated kaolinite was also studied. A high efficiency DSSC requires a photo-electrode with a high surface area to effectively adsorb the dye. So the couple of TiO2/kaolinite photo-electrode was prepared for this purpose. It is considered that kaolinite can confine the incident light within the electrode and can also improve the conduction of electrons. In this system, kaolinite also has an important role to increase the photostability of bixin. Another factor affecting the performance of DSSC is the important role of the electrolyte. In these studies, cyclic organic carbonates that have a high dielectric constant and also a high boiling point (above 300oC) were evaluated as solvents in the electrolyte. These works were carried out in four stages: (1) extraction, purification and characterization of bixin, (2) preparation, characterization and activation of kaolinite, (3) study of adsorption of bixin on the surface of kaolinite and TiO2, and (4) manufacturing of bixin sensitized solar cell (BSSC). The results show that the accelerated solvent extraction using a mixture of 60% cyclohexane and 40% acetone can be an effective method of extraction for bixin. After purification by flash chromatography, bixin with a degree of purity of 99.86% was isolated. It is composed of 88.11% cisbixin and 11.75% di-cis-bixin. The activation of calcined kaolinite (metakaolinite) by ammonia is a good method to produce kaolinite with very high specific surface area and a higher Si/Al ratio. The absorption study bixin has shown that the dimethyl carbonate is a suitable solvent for bixin. It allows bixin to have a high absorption coefficient and good adsorption characteristics onto the surface of the photo-electrode. The monolayer adsorption of bixin on the surface of TiO2 or kaolinite is more favorable to obtain higher energy efficiency. The presence of activated metakaolinite in the photo-electrode TiO2 has proven to improve the performance and stability of the BSSC compared to the BSSC manufactured with the pure TiO2 photo-electrode. These performances are reproducible. The electrolyte has a synergistic effect with the activated metakaolinite for improving the electrical parameters of the BSSC. Under a light intensity of 200 W/m2, the BSSC including a photo-electrode of TiO2 modified by 5% of the activated metakaolinite and KI/I2 electrolyte system in glycerol carbonate acetate produced an energy efficiency of (0.050+ 0.006)%, which is higher than that of the BSSC comprising a pure TiO2 photoelectrode (0.027+0.012)%. The use of LiI/I2 a redox couple in the glycerol carbonate acetate produces the maximum energy efficiency of (0.086+0.014)%. Its function of energy storage and loading worked well until the third day of analysis. To date, the BSSC manufactured using the photoelectrode TiO2 modified by activated metakaolinite is 16 times more stable than the BSSC manufactured using the pure TiO2 photo-electrode
Développement d'une méthode d'évaluation multi-indicateurs des systèmes agro-industriels, basée sur la pensée cycle de vie, pour une éco-conception des procédés de production by Remi Julio( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

The biorefinery concept, developed to face fossil resources dependence, aims to design a wide variety of products (biofuels, materials, chemicals ...) based on the development of renewable resources such as plant biomass. The establishment of biorefineries must be based on ecodesigned processes to optimize the environmental performance of the biomass processing chain. Nevertheless, eco-designing innovative processes can be complex due to multiple configurations and the lack of related specific and reliable data. Thereby, the aim of this research work is to develop a multi-indicator evaluation method for the eco-design of agro-industrial and biorefinery processes. The general approach is based on coupling Process Engineering and Life Cycle Assessment fields. Indeed, process modeling, based on mathematical or semi-empirical models (notably resulting from designs of experiments) and process simulation are applied to facilitate the life cycle inventory step by predicting detailed mass and energy balances. Then these data can be used to perform a prospective Life Cycle Assessment of the process. By iteration, it is possible perform data prediction and to test several operating conditions sets for the process, to enhance its environmental performance, by determining optimal operating conditions and by identifying the most environmentally friendly unit operations. The methodology and its associated tool have been tested on different biorefinery processes, involving various biomasses: micro-algae, wheat coproducts and wood
La complexité des simples - Caractérisations chimique et biologique de combinaisons hydrolats-huiles essentielles et huiles essentielles-huiles essentielles pour l'objectivation d'effets conservateurs de produits phytothérapeutiques. by Yann-Olivier Marie Hay( )

1 edition published in 2015 in French and held by 1 WorldCat member library worldwide

The parapharmaceutical industry as well as the cosmetics industry is looking for natural alternatives to synthetic preservatives. This interest is linked to the requirement of the consumer and the will to develop eco-designed innovative products. Antioxidant and antimicrobial activities of essential oils are interesting options, however costs and organoleptic impacts should be considered. As part of this thesis, the antioxidant and antimicrobial activities of essential oil-hydrosol and essential oil-essential oil of Lippia alba, Rosmarinus officinalis and Thymus vulgaris were evaluated to objectify their preservative potential for herbal products. Initially, the impact of a distillation method using the aqueous macerate of a part of vegetal material as vapor source was evaluated on the physicochemical properties of hydrosols and essential oils of Thymus vulgaris and Rosmarinus officinalis grown in southern Bogotá Colombia. Then, distillates and hydrosols with significant biological activity as well as the essential oil of Lippia alba were combined by pairs. The antiradical and microbicidal activities were evaluated respectively by ABTS and by the methods of microdilution and agar diffusion. Significant results were obtained with the essential oil-essential oil combinations especially in the case of the combination of essential oils of T. vulgaris and L. alba with a decrease of the IC50 of 2,9 (T. vulgaris essential oil alone) to 1,4 µL/L as well as in the specific case of the T. vulgaris hydrosol and essential oil combination with an IC50 of 2,1 µL/L. Similarly, the latter combination presented a synergy effect by decreasing the Minimal Bactericidal Concentration of the essential oil of Thyme from 0,4 to 0,1µL/mL. The different results are discussed as well as their impacts in both industrial and therapeutic domains
 
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Audience level: 0.95 (from 0.95 for Emulsions ... to 0.96 for Système c ...)

Alternative Names
CAI

Chimie Agro-Industrielle

Laboratori de Química Agroindustrial

Laboratory of Agro-Industrial Chemistry

LCA

UMR 1010

UMR1010

Languages
French (14)

English (6)