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See detailProduction and toxicity of γ-decalactone and 4-hydroxydecanoic acid from Rhodotorula aurantiaca
Alchihab, Mohamed ULg; Destain, Jacqueline ULg; Aguedo, Mario ULg et al

Poster (2009)

The objective of this study was to compare the production of γ- decalactone in different scales and to study the effects of 4- hydroxydecanoic acid and γ-decalactone on the growth of R. aurantiaca. The ... [more ▼]

The objective of this study was to compare the production of γ- decalactone in different scales and to study the effects of 4- hydroxydecanoic acid and γ-decalactone on the growth of R. aurantiaca. The effect of gum tragacanth on the production of γ-decalactone by R. aurantiaca was evaluated. [less ▲]

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See detailProduction at the Curie Level of No-Carrier-Added 6-18F-Fluoro-L-Dopa
Libert, Lionel ULg; Franci, Xavier; Plenevaux, Alain ULg et al

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (2013), 54(7), 1154-1161

6-18F-fluoro-L-dopa (18F-FDOPA) has proven to be a useful radiopharmaceutical for the evaluation of presynaptic dopaminergic function using PET. In comparison to electrophilic synthesis, the no-carrier ... [more ▼]

6-18F-fluoro-L-dopa (18F-FDOPA) has proven to be a useful radiopharmaceutical for the evaluation of presynaptic dopaminergic function using PET. In comparison to electrophilic synthesis, the no-carrier-added (NCA) nucleophilic method has several advantages. These include much higher available activity and specific activity. Recently, we have described an NCA enantioselective synthesis using a chiral phase-transfer catalyst. However, some chemicals were difficult to implement into a commercially available synthesizer, restricting access to this radiopharmaceutical to only a few PET centers. Methods: In this paper, 2 important chemical improvements are proposed to simplify production of 18F-FDOPA, resulting in straightforward automation of the synthesis in a commercially available module. Results: First, a fast, simple, and reliable synthesis of 2-18F-fluoro-4,5-dimethoxybenzyl iodide on a solid phase support was developed. Second, a phase-transfer catalyst alkylation of a glycine derivative at room temperature was used to enable enantioselective carbon–carbon bond formation. After hydrolysis and high-performance liquid chromatography purification, a high enantiomeric excess of 18F-FDOPA (~97%) was obtained using a chiral catalyst available from a biphenyl 3 substrate. The total synthesis time was 63 min, and the decay-corrected radiochemical yield was 36% +/- 3% (n = 8). Conclusion: By exploiting the advantages of this NCA approach, using a starting activity of 185 GBq of NCA 18F-fluoride, high activities of 18F-FDOPA (> 45 GBq) with high specific activity (>753 GBq/mmol) are now available at the end of synthesis for use in clinical investigations. [less ▲]

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See detailProduction bovine et bien-être animal
Nicks, Baudouin ULg; Dufrasne, M.

Article for general public (1997)

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See detailLa production céréalière biologique en Wallonie
Debode, F.; Schiepers, H.; Burny, Philippe ULg

in Destain, J.-P.; Bodson, B. (Eds.) Livre Blanc "Céréales", édition février 2013 (2013)

Detailed reference viewed: 17 (6 ULg)
See detailProduction d’acide gluconique, reconnu comme molécule prébiotique, par transformation enzymatique à partir d’hydrolysats d’amidon
Schömig, Alexandra; Goffin, Dorothée ULg

Report (2008)

Une méthode tout à fait originale a été mise au point dans le but de produire de l’acide gluconique à partir d’hydrolysats d’amidon (gluco-oligosaccharides en liaisons -(1-4)). En effet, dans de ... [more ▼]

Une méthode tout à fait originale a été mise au point dans le but de produire de l’acide gluconique à partir d’hydrolysats d’amidon (gluco-oligosaccharides en liaisons -(1-4)). En effet, dans de nombreuses industries traitant des produits d’origine végétale, l’amidon constitue un co-produit qu’il est intéressant de valoriser. Dans ce contexte, le présent travail présente une voie de valorisation originale des hydrolysats d’amidon. Cette méthode comporte une première étape qui consiste en l’hydrolyse par voie enzymatique la plus poussée possible des maltooligosaccharides de la fraction amylose dans le but d'obtenir un maximum de glucose. Deux enzymes ont été testées : l’-glucosidase de Bacillus stearothermophilis et l’amyloglucosidase d’Aspergillus niger. Ces dernières ont été testées sur trois différents substrats : le glucose (pour vérifier l’absence d’une activité de transglucosylation dans les conditions de travail), le maltose et un mélange de maltooligosaccharides de DP 1 à 4. Aucune activité de transglucosylation n’est observée. L’-glucosidase hydrolyse le maltose jusqu’à une teneur résiduelle de 44% et les maltooligosaccharides sont clivés suivant des cinétiques proches, de sorte qu’après 5h30 de réaction, il ne reste que 5 à 10 % de ces maltooligosaccharides. L’amyloglucosidase elle hydrolyse très rapidement les DP supérieurs qui forment alors du maltose qui lui limitera fortement la vitesse de réaction. La deuxième étape consiste en la conversion du glucose libéré en acide gluconique à l’aide d’une glucose oxydase. Les conditions optimales de réaction et l’influence de différents paramètres sur la vitesse et le rendement de la réaction ont été étudiés sur des solutions de glucose. Une régulation du pH s’est avérée indispensable pour rester dans les conditions optimales de l’enzyme et l’utilisation de milieux tamponnés à été préféré à celle d’un pHstat. L’influence de l’ajout d’une quantité d’enzyme plus importante sur la vitesse de réaction a été mise en évidence ainsi que l’importance de l’apport en O2 substrat de la réaction. En effet un débit d’air comprimé de 3L/min, permet un taux de conversion du glucose en acide gluconique de 70 % en seulement 5 h (conversion à 99,9 % en  10h) de réaction au lieu de 30 % après plus de 20 h de réaction en système non aéré. L’agitation s’est également avéré être un paramètre important, celle-ci permettant l’homogénéisation du milieu ainsi qu’une meilleure dispersion de l’O2. Une réaction a ensuite été réalisée dans les conditions optimales mais en l’absence de l’enzyme pour vérifier l’absence d’oxydation résiduelle due à l’apport important d’oxygène. Il en ressort que la réaction a besoin de l’abaissement de sa barrière énergétique par l’enzyme pour avoir lieu. Enfin, la spécificité de l’enzyme a été testée (absence de réactions croisées) sur des sucres de structure proche. Le maltose, cellobiose et les maltooligosaccharides ne sont pas oxydés ou sont oxydés à des vitesses telles que la réaction n’a pas lieu dans nos conditions. Seul le saccharose est oxydé et donne différents acides dont l’acide gluconique. Enfin, l’acide gluconique peut être purifié de ses impuretés (glucose et maltooligosaccharides résiduels) par rétention sur résine échangeuse d’anions (forme AcO-). Dans un premier temps, la séparation est réalisée avec un passage unique sur résine (100mg de résine par ml de solution). Néanmoins, une large proportion de l’acide gluconique est perdu dans l’éluat et les deux lavages alors qu’à peine 0,2% de glucose sont retrouvés au niveau de la fraction d’élution de la résine au HCl. Lors d’une seconde purification, l'utilisation d'une plus grande quantité de résine (200 mg/ml) et le passage des éluats sur une seconde résine, pour pallier à la saturation de la première ont permis de réduire à 17 % (de la masse de départ) l’acide gluconique retrouvé dans l’éluat final et à nouveau d’obtenir une fraction AG très pauvre en glucose (0,022%). [less ▲]

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See detailProduction d’arômes de type lactone par des levures.
Alchihab, Mohamed ULg; Destain, Jacqueline ULg; Aguedo, Mario ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2010), 14(4), 681-691

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See detailProduction d'énergie et environnement
Nicolas, Jacques ULg

Report (1993)

Fondation Universitaire Luxembourgeoise was involved in a study supported by European Commission to analyse the various possibilities of energy production in Rio Grande do Sul, in Bresil. The present ... [more ▼]

Fondation Universitaire Luxembourgeoise was involved in a study supported by European Commission to analyse the various possibilities of energy production in Rio Grande do Sul, in Bresil. The present report is a preliminary overview of the pro and con of different energy production systems on the environmental point of view. [less ▲]

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See detailProduction d'esquisses créatives en conception digitale
Leclercq, Pierre ULg; Mayeur, A.; Darses, F.

in Agon, C.; Delerue, O. (Eds.) Proceedings of the 19th International Conference of the Association Francophone d'Interaction Homme-Machine, IHM (2007)

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See detailLa production d'hydrogène par fermentation anaérobie: Voies d'optimalisation et d'application du bioprocédé
Beckers, Laurent ULg

Doctoral thesis (2013)

The emergence of environmental and societal issues caused by the fossil fuels consumption and the simultaneous increase of the energetic needs will lead the society to evolve into a new energetic system ... [more ▼]

The emergence of environmental and societal issues caused by the fossil fuels consumption and the simultaneous increase of the energetic needs will lead the society to evolve into a new energetic system. The creation of the hydrogen society could bring a suitable and sustainable solution since the production and use of hydrogen could be operated at higher yields than the fossil fuels economy and produce energy while generating only water vapour as co product. However, in order to get rid of the fossil fuels consumption, there is a need to diversify the hydrogen production processes and technology, currently still based on CO2—emitting technologies. The so-called “dark fermentation” process is based on strict of facultative anaerobic bacteria producing biohydrogen and soluble metabolites as a fermentation co product. These microorganisms consume organic substrates such as in wastewater to achieve their growth. The biohydrogen technology has been studied during several years in laboratory but still is not mature to be brought at an industrial scale. Indeed, there is first a need to improve the performances (such as the H2 yields and production rates) to achieve the technical and economical requirements. This thesis investigates and discusses various possibilities in order to bring the biohydrogen production process to a larger scale. The strain investigated in this work, Clostridium butyricum, can achieve high performances (in terms of hydrogen yields, about 1.9 to 2.2 molH2·molglucose -1 and production rates, about 50 to 110 mLH2·L-1·h-1 in batch or sequencing-batch cultures) and is able to consume simple and more complex substrates. However, being a strict anaerobic strain, its uses in pure culture requires the achievement of strong anaerobic conditions using artificial and costly means. Moreover, even if the work in pure culture has some advantages at the laboratory scale, it is inappropriate to larger volumes of bioreactor. Therefore, mixed cultures were investigated in batch and sequencing-batch bioreactors, resulting in a decrease by about 30 to 50% of the yields (down to 1.2 to 1.7 molH2·molglucose -1). The mixed cultures reached however comparable or higher performances than the scientific literature confirming the interest of the approach suggested in this work. However, the performances need to be further enhanced in order to make the process economically possible. Therefore, improvements of the yields and the rates were proposed. On the one hand, the yields were increased by 55 to 100% (up to 3.1 molH2·molglucose -1) by improving the mass transfer conditions and, by the way, decreasing the dissolved hydrogen concentration in the liquid media. These considerations led to the design of a novel biodisc bioreactor working continuously and allowing the efficient hydrogen mass transfer. In mixed culture, the biodisc bioreactor reached high performances (H2 yields of 2.4 molH2·molglucose -1 and H2 rates of 600 mLH2·L-1·h-1), showing the interest of the original design and of the “mass transfer” approach achieved in this work. On the other hand, the addition in the culture medium of small quantities of metallic nanoparticles showed a catalytic-like effect by enhancing the hydrogen production rate by about 40 to 100%. Ending this work, the general discussion evidences the advantages of the different techniques suggested in the work and compares them to the recent scientific literature. Furthermore, perspectives are given in terms of scientific outlooks, considering the economical, environmental and technical aspects, in order to bring the hydrogen production process at a large scale. [less ▲]

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See detailProduction d'oligosaccharides à partir de gomme de caroube
Simon, Mathilde ULg

Master's dissertation (2010)

The general framework of this study is the discovery of prebiotics and more specifically the production of oligosaccharides by enzymatic hydrolysis of locust bean gum. These, though not much studied ... [more ▼]

The general framework of this study is the discovery of prebiotics and more specifically the production of oligosaccharides by enzymatic hydrolysis of locust bean gum. These, though not much studied, could present a rich prebiotics potential. The aim of this work was the purification of beta-mannanases located in germinating carob seeds as well as the validation of a AEC-PAD method applicable to the analysis of locust bean gum hydrolysates. Therefore, it has permitted to establish a concentration and purification procedure of beta-mannanases and to determine a suitable preservation method of enzymatic extracts. An original method to evaluate the enzymatic activity by viscosity measurements has also been developed and permits the study of the evolution of enzymatic activities during germination. The validation method of characterization and quantification of (galacto)-manno-oligosaccharides constitutes the last part studied. Seven performance criteria calculated for each of the nine standards were used to validate the method. It has then been used to analyze locust bean gum hydrolysates. The results of this work are the first of a new research theme. They offer many opportunities and future applications. [less ▲]

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See detailProduction de l'urbanisation et infrastructures de viabilisation
Halleux, Jean-Marie ULg; Lambotte, Jean-Marc ULg; Bruck, L. et al

in Ruimte & Planning (2003), (3), 197-210

Detailed reference viewed: 46 (8 ULg)
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See detailLa production de bioéthanol à partir de biomasse lignocellulosique
Didderen, I.; Destain, Jacqueline ULg; Thonart, Philippe ULg

Article for general public (2010)

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See detailProduction de biohydrogène à partir de biomasses
Hiligsmann, Serge ULg

Scientific conference (2014, October 23)

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See detailLa production de biohydrogène à partir de substrats carbohydratés : état de l'art
Hiligsmann, Serge ULg; Beckers, Laurent ULg; Masset, Julien ULg et al

in Récents progrès en génie des procédés (2011, December 01)

Hydrogen is being considered as an ideal and clean energy carrier. The recent advances to produce biohydrogen from renewable sources such as biomass and particularly by fermentation of carbohydrate-rich ... [more ▼]

Hydrogen is being considered as an ideal and clean energy carrier. The recent advances to produce biohydrogen from renewable sources such as biomass and particularly by fermentation of carbohydrate-rich substrates from agriculture and agro-industries appear promising. Such a process enables both organic waste treatment and renewable energy production to be coupled. The paper presents the state of the art about the different hydrogen-producing microorganisms and the parameters that have been investigated in order to improve the hydrogen production yields and rates. [less ▲]

Detailed reference viewed: 69 (17 ULg)