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See detailCHIMIE THÉORIQUE ET PHYSIQUE APPLIQUÉE À L’ANALYSE STRUCTURALE DES BIOMOLÉCULES (CG 204) - Exercices
Gillet, Sébastien ULg; Richel, Aurore ULg; Wathelet, Bernard ULg

Learning material (2011)

Le cours est axé sur l'apprentissage de l'analyse spectrale (IR, MS, RMN, RMN2D) des molécules organiques ou biologiques.L'interprétation qui en découle permettra d'en retrouver la structure.

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See detailGreen Chemistry in Wallonia. Focus on lignocellulosic transformations.
Richel, Aurore ULg; Paquot, Michel ULg

Conference (2011, February 10)

In the context of the valorisation of agricultural resources, the development of new sustainable strategies has gained attention. In this sense, this speech describes some major actions and contributions ... [more ▼]

In the context of the valorisation of agricultural resources, the development of new sustainable strategies has gained attention. In this sense, this speech describes some major actions and contributions undertaken in Wallonia around both “green chemistry” and “biorefinery” concepts. [less ▲]

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See detailLipase-catalyzed synthesis of L-cysteine glucosyl esters in organic media
Valepyn, Emmanuel ULg; Nys, Joël ULg; Richel, Aurore ULg et al

in Biocatalysis & Biotransformation (2011), 29(1), 25-30

New sugar amino acids were synthesized by enzymatic esterification of D -glucose with L -cysteine using immobilized lipase B from Candida antarctica in a mixed solvent system composed of 2-methyl-2 ... [more ▼]

New sugar amino acids were synthesized by enzymatic esterification of D -glucose with L -cysteine using immobilized lipase B from Candida antarctica in a mixed solvent system composed of 2-methyl-2-butanol and dimethyl sulfoxide. Addition of small quantities of water to the medium improved the glucose conversion yield by a factor of two. [less ▲]

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See detailLe bioraffinage, une alternative prometteuse à la pétrochimie
Laurent, Pascal ULg; Roiz, Julie ULg; Wertz, Jean-Luc ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2011), 15(4), 597-610

Because of the price increase of fossil resources, of their uncertain availability and because of environmental concerns, alternative solutions able to mitigate global warming, and reduce the consumption ... [more ▼]

Because of the price increase of fossil resources, of their uncertain availability and because of environmental concerns, alternative solutions able to mitigate global warming, and reduce the consumption of fossil fuels and carbon dioxide emissions should be promoted. The replacement of petroleum with biomass as raw material for bioenergy (biofuels, power and heat) and chemical production is an interesting option and is the driving force for the development of biorefinery complexes that will have a critical role to play in our common future. A biorefinery is a facility that integrates biomass conversion processes and equipment to produce fuels, power, heat and chemicals from biomass. In biorefinery, almost all types of biomass feedstocks can be converted to different classes of biofuels and biochemicals through various processes that maximize economic and environmental benefits, while minimizing waste and pollution. Through the integration of green chemistry into biorefineries, and the use of low environmental impact technologies, future sustainable production chains of biofuels and high value chemicals from biomass can therefore be established. Currently, the green biorefinery, the whole-crop biorefinery, the oilseed biorefinery and the lignocellulosic feedstock biorefinery are favoured in research, development and industrial implementation, essentially through fully integrated biorefinery complexes. [less ▲]

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See detailImpact of formic/acetic acid and ammonia pre-treatments on chemical structure and physico-chemical properties of Miscanthus x giganteus lignins
Vanderghem, Caroline ULg; Richel, Aurore ULg; Jacquet, Nicolas ULg et al

in Polymer Degradation & Stability (2011), 96(10), 1761-1770

Miscanthus x giganteus was treated with formic acid/acetic acid/water (30/50/20 v/v) for 3 h at 107 C and 80° C, and soaking in aqueous ammonia (25% w/w) for 6 h at 60 C. The effects of these ... [more ▼]

Miscanthus x giganteus was treated with formic acid/acetic acid/water (30/50/20 v/v) for 3 h at 107 C and 80° C, and soaking in aqueous ammonia (25% w/w) for 6 h at 60 C. The effects of these fractionation processes on chemical structure, physico-chemical properties and antioxidant activity of extracted lignins were investigated. Lignins were characterized by their purity, carbohydrate composition, thermal stability, molecular weight and by Fourier transform infrared (FTIR), 1H and quantitative 13C nuclear magnetic resonance (NMR), adiabatic broadband {13C-1H} 2D heteronuclear (multiplicity edited) single quantum coherence (g-HSQCAD). The radical scavenging activity towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) was also investigated. Formic/acetic acid pretreatment performed in milder conditions (80° C for 3 h) gave a delignification percentage of 44.7% and soaking in aqueous ammonia 36.3%. Formic/acetic acid pretreatment performed in harsh conditions (107°C for 3 h) was more effective for extensive delignification (86.5%) and delivered the most pure lignin (80%). The three lignin fractions contained carbohydrate in different extent: 3% for the lignin obtained after the formic/acetic acid pretreatment performed at 107 C (FAL-107), 5.8% for the formic/acetic acid performed at 80°C (FAL-80) and 13.7% for the ammonia lignin (AL). The acid pretreatment in harsh conditions (FAL-107) resulted in cleavage of b-O-4' bonds and aromatic C-C. Repolymerisation was thought to originate from formation of new aromatic C-O linkages. Under milder conditions (FAL-80) less b-O-4' linkages were broken and repolymerisation took place to a lesser extent. Ammonia lignin was not degraded to a significant extent and resulted in the highest weight average 3140 g mol -1. Despite the fact of FAL-107 repolymerisation, significant phenolic hydroxyls remained free, explaining the greater antioxidant activity. [less ▲]

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See detailLa chimie verte
Richel, Aurore ULg

in Probio (2011), (septembre 2011, n°4), 171-176

Le concept de « chimie verte », défini pas Anastas et Warner en 1998, a pour but de « concevoir des produits et des procédés de synthèse permettant de réduire ou d’éliminer l’utilisation et la génération ... [more ▼]

Le concept de « chimie verte », défini pas Anastas et Warner en 1998, a pour but de « concevoir des produits et des procédés de synthèse permettant de réduire ou d’éliminer l’utilisation et la génération de substances dangereuses ». La chimie verte a donc pour objectif d’offrir une approche aux problèmes liés à la pollution et à la sécurité en mettant en oeuvre des solutions scientifiques innovantes. Parmi ces avancées scientifiques, l’utilisation des techniques de catalyse, de chauffage alternatif (micro-ondes) et l’exploitation des ressources végétales renouvelables en substituts aux matières premières fossiles sont sans nul doute les piliers des recherches effectuées en matière de chimie verte. [less ▲]

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See detailImpact of a formic/acetic acid treatment of beech wood on delignification and chemical structure of lignins
Simon, Mathilde ULg; Richel, Aurore ULg; Vanderghem, Caroline ULg et al

Conference (2011)

Lignocellulosic substrates constitute a promising alternative resource for the sustainable production of energy (biofuels), biobased products and organic compounds. In the past, the extraction and the ... [more ▼]

Lignocellulosic substrates constitute a promising alternative resource for the sustainable production of energy (biofuels), biobased products and organic compounds. In the past, the extraction and the valorization of cellulose (into fermentescible glucose) constituted the central axis of lignocellulosic biorefinery processes. Degraded hemicelluloses and lignins were however recovered as side-products with no possibilities of high-added value applications. Within the context of an integrated biorefinery, and for economic reasons, the recovery and the non-energetic transformation of lignins have opened recently new horizons. Lignin is a cross-linked phenolic polymer and is considered as a potential alternative to petrochemical polymers or as a source of antioxidants for cosmetics and food industry, resins, chelating agent... As the final application of lignin is dependent of both extraction process and type of lignocellulosic sources, the development of fast and efficient physicochemical characterization methods is thus a prerequisite to optimize extraction processing conditions. In this study, beech wood particles (Fagus sylvatica L.) collected in the region of Gaume (Belgium) were delignified at atmospheric pressure by a mixture of formic acid/acetic acid/water. The effect of cooking time and temperature was evaluated on delignification and on chemical structure of lignins obtained by precipitation from the black liquor after treatments. To study the delignification, a central composite design and response surface methodology were used for the optimization of two treatments parameters, i.e. time (between 1h30 and 4h30) and temperature (from 87 to 107°C). These two variables were optimized for delignification yield, pulp yield, concentration of degradation products (furfural and hydroxymethylfurfural) and for the amount of residual linkages between lignin constitutive units. On the basis of our results, higher delignification yields were obtained when cooking time and temperature increased. However, for high cooking times and temperatures, pulp yield decreased because hemicelluloses and cellulose were hydrolyzed and the production of furfural and hydroxymethylfurfural was augmented. The structural and physico-chemical features of extracted lignins were investigated with different analytical tools, namely infrared spectrometry, thermogravimetric analysis, size-exclusion chromatography, mono-dimensional nuclear magnetic resonance (NMR 1H and NMR 13C) and bidimensional NMR (heteronuclear HSQC experiments). The characterization of lignins indicated the occurrence of a repolymerization phenomenon when both cooking time and temperature increased. Indeed, HSQC NMR spectra presented oxidized syringyl units. Otherwise, thermogravimetric analysis and HSQC analysis showed the presence of hemicelluloses in lignin samples from soft treatments (1h30, 87°C). Some linkages between lignin and hemicelluloses were not cleaved under these experimental conditions. [less ▲]

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See detailImpact of the treatment conditions of a formic/acetic acid delignification method on chemical structure and antioxidant activity of beech wood lignin
Simon, Mathilde ULg; Vanderghem, Caroline ULg; Richel, Aurore ULg et al

Poster (2011)

The interest in lignocellulosic substrates is increasing because they are clearly identified for their high potential of development in energy and value-added molecules production. Indeed lignocellulosic ... [more ▼]

The interest in lignocellulosic substrates is increasing because they are clearly identified for their high potential of development in energy and value-added molecules production. Indeed lignocellulosic biomass constitutes a promising resource for a sustainable production of organic compounds and biobased products that could progressively replace molecules from the petrochemical industry. Until now lignocellulosic substrates were mainly used for the valorization of cellulose. Hemicelluloses and lignins were less valorized and often degraded after the process. However, due to their phenolic structure, lignins can be valorized in a lot of high-valued applications like vanillin production, replacement of petrochemical polymers, antioxidants for cosmetics and food industry, resins… In this study, a representative sample of beech wood (Fagus sylvatica L.) was collected in the region of Gaume in Belgium. Beech wood was delignified at atmospheric pressure by an organosolv process using a mixture of formic acid/acetic acid/water. The effect of cooking time and temperature was evaluated on the structure, physico-chemical properties and antioxidant activity of the lignins obtained from the black liquor after treatments. The structural and physico-chemical characteristics of the lignins were investigated with different tools like infrared spectrometry, thermogravimetric analysis, gel permeation chromatography after acetylation of lignins, NMR 1H, 13C and HSQC. The antioxidant activity was assessed by a spectrophotometric method using the α,α-diphenyl-β-picrylhydrazyl radical (DPPH). [less ▲]

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See detailOptimization of a formic/acetic acid treatment of beech wood (Fagus sylvatica L.) for delignification
Simon, Mathilde ULg; Richel, Aurore ULg; Vanderghem, Caroline ULg et al

Poster (2011)

Lignin is a promising molecule constituting a renewable alternative to some petrochemical industry products. Lignin is an aromatic cross-linked heteropolymer composed of three phenylpropanoids (p ... [more ▼]

Lignin is a promising molecule constituting a renewable alternative to some petrochemical industry products. Lignin is an aromatic cross-linked heteropolymer composed of three phenylpropanoids (p-hydroxyphenyl, guaiacyl and syringyl units) linked together via radical coupling reactions by specific ether or carbon-carbon bonds. With this phenylpropanoid structure, lignin is a rich resource of biobased products that could find high-valued applications in a lot of different areas like petrochemical polymer reinforcement and replacement, antioxidants, stabilizers, resins and vanillin production... The first challenge of the valorization of lignins is their extraction from raw materials. Lignins can be found in different lignocellulosic substrates like grasses, softwood and hardwood. This extraction process needs the development of suitable biomass treatments, allowing efficient lignin recuperation without degradation. This one could lead to the loss of some interesting properties and so of some valorization possibilities. In this study, beech wood (Fagus sylvatica L.) was collected in the region of Gaume (Belgium). Beech wood particles were delignified at atmospheric pressure by a mixture of formic acid/acetic acid/water. A central composite design and response surface methodology were used for the optimization of treatment parameters for delignification. The optima of two independent variables, namely time (1h30, 3h, 4h30) and temperature (87°C, 97°C, 107°C), were determined on delignification yield, pulp yield, concentration of degradation products (furfural and hydroxymethylfurfural). Moreover, the impact of these two variables on the amount of residual linkages between phenylpropanoid units was evaluated by semi-quantitative bidimensional nuclear magnetic resonance spectroscopy (NMR-HSQC). Our results highlight that the delignification yields increase when cooking time and temperature are elevated. Nevertheless, under these conditions, pulp yield decreases as hydrolysis of hemicelluloses and cellulose occurs. The hydrolysates of carbohydrates (free sugars or oligosaccharides) are contained in the black liquor. At elevated temperature and time, the amount of degradation products in the black liquor is increased. [less ▲]

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See detailUtilisation des micro-ondes pour la conversion hydrolytique de la biomasse lignocellulosique
Richel, Aurore ULg; Paquot, Michel ULg

in Chimie Nouvelle (2011), 108

The use of microwave is described as a non conventional and original heating source for both pretreatment and hydrolysis of lignocellulosic agroresources into high added value materials. Advantages of ... [more ▼]

The use of microwave is described as a non conventional and original heating source for both pretreatment and hydrolysis of lignocellulosic agroresources into high added value materials. Advantages of this approach are presented in terms of reduced reaction times and improved selectivities and yields. The limitations of this technology are also evaluated. [less ▲]

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See detailCatalytic conversion of lignin to low molecular weight compounds
Verziu, Marian; Richel, Aurore ULg; Filip, Petru et al

Conference (2011)

Nowadays lignocellulosic materials represent the higher renewable natural resource in the world. These materials consist of 34–50% cellulose, 19–34% hemicellulose and 11–30% lignin. Unlike cellulose ... [more ▼]

Nowadays lignocellulosic materials represent the higher renewable natural resource in the world. These materials consist of 34–50% cellulose, 19–34% hemicellulose and 11–30% lignin. Unlike cellulose, lignin is a three-dimensional aromatic polymer including three main phenylpropane units, namely p-coumaril, coniferyl and sinapyl alcohol which are linked by C-O-C or C-C bonds. To valorize this material it is necessary to achieve its depolymerization to monomers or dimers that typically results from the cleavage of β-O-4 linkages. Literature already reported several approaches to depolymerize lignin using both homogeneous and heterogeneous catalysts. Yuan et all have considered a homogeneous route in this scope using NaOH as catalyst. This solution is however by far non-green leading to no-recyclable wastes. Heterogeneous catalysts offer an alternative. The use of noble metals like Pt or Rh supported on carbon, at 473 K, under H2 pressure, was shown to yield over 50% in monomers and dimers . Cheaper metals as copper represent a more versatile route but the reported example uses high energetic supercritical conditions. The use of inexpensive metals such as Ni may offer another alternative. In this study we propose an inexpensive route presenting results obtained using as active species, nickel in different environments such as NiOx, (NiAl)Ox, (NiMgAl)Ox thus looking also for the effect of basicity in this reaction. These materials were prepared using specific protocols and characterized by several techniques like: XRD, DRIFT, BET, and TEM. The catalysts were tested in autoclave conditions at different temperature (423-473K) under H2 pressure. The lignin was extracted from Miscanthus plants into formic acid / acetic acid / water mixture. Since it is not soluble in water its solubilization was achieved in an [BMIM]OAc ionic liquid, selected from a screening of a series of ILs. On the other side, the analysis of the reaction products is a complicate issue in this chemistry. This was carried out with a chromatographic system equipped with a Detector Triple Quad LC/MS, and a MS Ion Source type, working simultaneously in both APCI and ESI modes. The analysis of the reaction products indicated both polar and less polar compounds with a m/z signal varying from 80 till 900. The population of the different class molecules was carefully analyzed as a function of the nature of the catalyst and the reaction conditions. The higher extent of lignin depolymerization was around 54% and was obtained using a (NiAl)Ox catalyst. Under these conditions the predominant class was that with m/z of 200-300 a.u. Finally the stability of the catalysts was checked looking for their separation and recyclability in several successive cycles. [less ▲]

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See detailDiallyl disulfides: comparison between classical and microwave-assisted synthesis
DETHIER, Bérénice ULg; Richel, Aurore ULg; Laurent, Pascal ULg et al

in Ioannou, Efstathia; Roussis, Vassilios (Eds.) Trends in Natural Products Research: Abstracts of the Phytochemical Society of Europe (2011)

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See detailCurrent perspectives on microwave-enhanced reactions of monosaccharides promoted by heterogeneous catalysts.
Richel, Aurore ULg; Laurent, Pascal ULg; Wathelet, Bernard ULg et al

in Catalysis Today (2011), 167

Involvment of heterogeneous catalysts as promoters of carbohydrate conversions, in synergy with microwaves as the heating source, is reported. This paper deals with the application of ion-exchange resins ... [more ▼]

Involvment of heterogeneous catalysts as promoters of carbohydrate conversions, in synergy with microwaves as the heating source, is reported. This paper deals with the application of ion-exchange resins, zeolites, clays and metal oxides as convenient mediators for key transformations of carbohydrates. A special emphasis is placed on the use of (doped) mineral supports, in solventless conditions, as clean promoters in combination with microwave dielectric heating. [less ▲]

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See detailMicrowave-assisted conversion of carbohydrates. State of the art and outlook.
Richel, Aurore ULg; Laurent, Pascal ULg; Wathelet, Bernard ULg et al

in Comptes Rendus Chimie (2011), 14

The valorisation of carbohydrates arising from the hydrolysis of renewable feedstocks (i.e. lignocellulosic biomass) is nowadays an area of outmost interest. In this context, the implementation of fast ... [more ▼]

The valorisation of carbohydrates arising from the hydrolysis of renewable feedstocks (i.e. lignocellulosic biomass) is nowadays an area of outmost interest. In this context, the implementation of fast, expeditious and cost-effective methodologies for the modification of these naturally occurring compounds is becoming a prerequisite. In this sense, the application of microwaves has gained progressive attention in laboratories for making a range of high-added value sugars derivatives scaffolds. Advantages of microwaves are numerous and include enhancement of reaction rates and yields, combined to improved regio-, chemo- and anomeric selectivities. Summary: 1. Introduction 2. Chemical transformations of monosaccharides Regioselective hydroxyls protections/deprotections Derivatisation at the anomeric position Other derivatisations Microwave-assisted click chemistry Synergy between microwaves and heterogeneous catalysis Enzymatic modifications of monosaccharides 3. Effect of microwave heating on polysaccharides Hydrolysis and pretreatment of cellulose Derivatisation of cellulose 4. Scale-up of microwave-promoted reactions 5. Conclusions [less ▲]

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See detailNew insights into the transformation of carbohydrates into platform chemicals
Richel, Aurore ULg; Wathelet, Jean-Paul ULg; Paquot, Michel ULg

Poster (2010, October 14)

The synthesis of furanic compounds from carbohydrates has become exciting in chemistry and in catalysis studies, because it represents one of the major routes for achieving sustainable energy supply and ... [more ▼]

The synthesis of furanic compounds from carbohydrates has become exciting in chemistry and in catalysis studies, because it represents one of the major routes for achieving sustainable energy supply and chemicals production.1 In particular, 5-hydroxymethylfurfural (5-HMF) and 2-furfural (2-F) occupy a pivotal place and are recognised as versatile and multi-functional starting points for the synthesis of a panel of precursors. Microwaves have readily appeared as a powerfull technique for accelerating reaction rates and increasing selectivities in the field of carbohydrate chemistry.3 In particular, their involvment in combination with heterogeneous catalysts have opened new vistas in the production of bio-oxygenated platform chemicals. The state of the art and main outlook of this strategy are reported here. [less ▲]

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See detailSynthèse assistée par Micro-ondes de dérivés d'acides uroniques
Laurent, Pascal ULg; Richel, Aurore ULg; Wathelet, Bernard ULg et al

Poster (2010, October 14)

At the moment, biorefining is increasingly seen as a promising alternative to petrochemical sector since it targets both the replacement of part of petroleum as a source of energy and the development of ... [more ▼]

At the moment, biorefining is increasingly seen as a promising alternative to petrochemical sector since it targets both the replacement of part of petroleum as a source of energy and the development of chemicals from the biomass, such as detergents, phytopharmaceutics, solvents, plastics, etc. The valorisation of carbohydrates arising from the hydrolysis of renewable feedstocks is therefore an area of outmost interest. In this context, uronic acids such as glucuronic acid (GlcA) or galacturonic acid (GalA) derived from widely available raw material such as hemicellulose or pectins represent important biocompatible and bioresorbable starting material. The quest of highly effective, environmentally friendly and straightforward chemical strategies to transform totally O-unprotected uronic acids into high valuable materials remains actually a particularly challenging task. A new strategy enabling the quantitative “one-pot” production of water-soluble monosubstituted D-glucofuranosidurono-6,3-lactones from unprotected D-glucuronic acid (D-GlcA) involving microwaves and an inexpensive siliceous-based promoter will be described. The use of a heterogeneous acid catalytic systems consisting of sulfuric acid impregnated onto silica (H2SO4/SiG60) or onto carbon (H2SO4/C), offers a green alternative to unrecyclable liquid sulfuric acid and permit the developpment of a truly eco-friendly green process, as these supported acids were readily separated from liquid products, without neutralization, by decantation or filtration, thus minimizing energy consumption and wastes. Faced with environmental concerns, this solventless methodology offers attractive features, including short reaction times, high yields and easy set-up and workup. [less ▲]

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See detailCARBOHYDRATE-BASED SURFACTANTS FOR FORMING AND STABILIZING COLLOIDAL SYSTEMS AS EMULSIONS AND FOAMS
Razafindralambo, Hary ULg; Blecker, Christophe ULg; Richel, Aurore ULg et al

in Abstracts book of 5th edition of world congress on emulsions (2010, October 12)

Carbohydrate-based surfactants (CBS) constitute a class of amphiphilic molecules with particular and common interests. These surface-active compounds can be produced from the most abundant renewable ... [more ▼]

Carbohydrate-based surfactants (CBS) constitute a class of amphiphilic molecules with particular and common interests. These surface-active compounds can be produced from the most abundant renewable materials allowing large product concept possibilities, and may occur in a large structural range with one or more hydrophilic head groups and hydrophobic chains with various linkers/spacers, thanks to numerous reactive functional groups in their basic structure. It is then possible to design a quasi-unlimited number of new compounds by (bio)-synthesis from various raw materials. This structural diversity can generate a wide range of properties, which could be developed in food and non-food applications. Our challenge is now to find out the most suitable molecular structures for the post-development of CBS, mainly for colloidal systems like emulsion, foam, and suspension. A pre-screening of the dynamic and equilibrium interfacial tensions and interfacial rheology properties of various CBS prepared by chemical, enzymatic, or chemo-enzymatic synthesis routes from the derivatives of bio-renewable substrates is carried out. Then, the characterization of emulsifying and foaming properties of pre-selected molecules is performed. These investigations are completed by the characterization of thermal properties of liquid suspensions and powders. Homologous series of two derivative compounds of glucuronic and galacturonic acids with mono- or bicatenar hydrophobic chains and different linkages (linear or cyclic ester, amide) have been chosen as CBS starting compounds. These were full characterized by spectroscopic techniques (RMN, SM, IR). The effect of the hydrophobic chain length and number, polar head group, and the linker on whole properties investigated is easily deduced. [less ▲]

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See detailMicrowave-assisted conversion of carbohydrates. State of the art and outlook.
Richel, Aurore ULg; Laurent, Pascal ULg; Wathelet, Bernard ULg et al

Conference (2010, May)

The valorisation of carbohydrates arising from the hydrolysis of renewable feedstocks (i.e. lignocellulosic biomass) is nowadays an area of outmost interest. In this context, the implementation of fast ... [more ▼]

The valorisation of carbohydrates arising from the hydrolysis of renewable feedstocks (i.e. lignocellulosic biomass) is nowadays an area of outmost interest. In this context, the implementation of fast, expeditous and cost-effective methodologies for the modification of these naturally occurring compounds is becoming a prerequisite. In this sense, the application of microwaves has gained progressive attention in laboratories for making a range of high-added value sugars derivatives scaffolds. Its advantages are numerous and include enhacement of reaction rates and yields combined to improved regio-, chemo- and anomeric selectivities. Since the first publications of Gedye et Giguere in 1986, the use of microwave has progressively emerged as a popular non conventional heating source in the field of organic synthesis.1 Nevertheless, its application in the area of carbohydrate chemistry is less documented.2, 3 Although research in this field is still in its infancy, recourse to microwaves often provides, with remarkable yields and atom efficiency, new carbohydrate-based structures that are not easily available by any another means (or only via painstaking multi-step protocols). This communication proposes therefore selected, recent and non exhaustive illustrations of the application of microwaves to promote famous carbohydrates “model” reactions. The scale-up of such microwave-assisted reactions is also presented. [less ▲]

Detailed reference viewed: 72 (13 ULg)