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See detailLes stratégies de valorisation de la biomasse en Région Wallonne
Richel, Aurore ULg

Scientific conference (2015, April 20)

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See detailFood Compounds from Meadow Grasshoppers
Paul, Aman ULg; Frederich, Michel ULg; Uyttenbroeck, Roel ULg et al

Poster (2015, March 15)

Eating insects as food, particularly grasshopper is practiced in many cultures throughout the world. Meadow grasshopper (Chorthippus parallelus) is commonly found in Europe and some part of Asia. It is ... [more ▼]

Eating insects as food, particularly grasshopper is practiced in many cultures throughout the world. Meadow grasshopper (Chorthippus parallelus) is commonly found in Europe and some part of Asia. It is already known that grasshoppers of Chorthippus species are consumed as food in countries such as Thailand. With the aim of evaluating the nutritional potential of this insect species the proximate nutritional composition of grasshoppers caught from the local fields was realized. Besides this, the fatty acid profile of extracted lipids, amino acid profile and mineral composition of the insect was also revealed. Results suggest that meadow grasshopper is an excellent source of protein and essential amino acids. Lipids extracted from the grasshopper have an interesting fatty acid composition. Also the grasshopper contains some minerals that are important for body. With such protein content, amino acid profile, fatty acid profile of the lipids and mineral content this grasshopper species could present an interesting alternate to conventional protein sources. [less ▲]

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See detailCaractérisation physico-chimique et structurale de la poudre et des ulvanes de l'algue ulva lactuca
Guidara, Mariem; Yaich, Hela; Garna, Haikel et al

Poster (2015, March 15)

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See detailScalable temperature induced stress for the large-scale production of functionalized Bifidobacteria
Nguyen, Huu Thanh ULg; Razafindralambo, Hary; Richel, Aurore ULg et al

in Journal of Industrial Microbiology & Biotechnology (2015)

The application of sub-lethal stresses is known to be an efficient strategy to enhance survival of probiotic bacteria during drying processes. In this context, we previously showed that the application of ... [more ▼]

The application of sub-lethal stresses is known to be an efficient strategy to enhance survival of probiotic bacteria during drying processes. In this context, we previously showed that the application of heat stress upon the entry into stationary phase increased significantly the viability of Bifidobacterium bifidum. However, this heat shock has been considered only in small scale bioreactor and no information is available for a possible scaling-up strategy. Five different operating scales (0.2 L, 2 L, 20 L, 200 L and 2000 L) have thus been tested and the results showed that the viability of B. bifidum increases from 3.15 to 6.57 folds, depending on the scale considered. Our observations pointed out the fact that the heat stress procedure is scalable according to the main outcome, i.e. increases in cell viability, but other factors have to be taken into account. Among these factors, dissolved carbon dioxide seems to play a significant role since it explain the differences observed between the test performed at lab-scale and in industrial conditions. [less ▲]

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See detailPreliminary characterisation of residual biomass from Hibiscus sabdariffa calyces
Beye, Cheikh ULg; Aguedo, Mario ULg; Hiligsmann, Serge ULg et al

in African Journal of Biotechnology (2015), 14(36), 2683-2692

Hibiscus. sabdariffa calyces are mainly used for different agro-food and beverages applications. The residual biomass generated contains various useful substances that were extracted and characterized. It ... [more ▼]

Hibiscus. sabdariffa calyces are mainly used for different agro-food and beverages applications. The residual biomass generated contains various useful substances that were extracted and characterized. It contained 23% (w/w) soluble pectic material, a food additive, extracted with hot acidified water (80°C, pH=1.5) and precipitated with ethanol. The molecular weight (28.5 kDa and 109.7 kDa), the degree of methylation (70.6% and 44.3%) and the degree of acetylation (19.0% and 4.9%) were determined for two Senegalese cultivars (koor and vimto respectively). The effect of the extraction method on these parameters was highlighted. The residual lignocellulosic material (LCM) was chemically degraded to monosaccharides and the amount of glucose and xylose (39% of dry LCM) determined to estimate its potential as feedstock for biofuels production. However, an enzymatic degradation test revealed a recalcitrant LCM, as only 50 to 55% of its polymeric glucose content was degraded to monosaccharides without pretreatment. Xylooligosaccharides (XOS) are functional foods with a real market potential as prebiotics, characterized by their degree of polymerization (DP). The production of XOS synthetized by the enzymatic degradation of LCM was monitored. The results of analyses performed showed that XOS produced had mainly DP3 and DP4 values. [less ▲]

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See detailProduction of biofuels and biomolecules in the framework of circular economy: A regional case study
Jacquet, Nicolas ULg; Haubruge, Eric ULg; Richel, Aurore ULg

in Waste Management & Research : The Journal of the International Solid Wastes & Public Cleansing Association (2015), 33(12), 1121-1126

Faced to the economic and energetic context of our society, it is widely recognised that an alternative to fossil fuels and oil-based products will be needed in the nearest future. In this way ... [more ▼]

Faced to the economic and energetic context of our society, it is widely recognised that an alternative to fossil fuels and oil-based products will be needed in the nearest future. In this way, development of urban biorefinery could bring many solutions to this problem. Study of the implementation of urban biorefinery highlights two sustainable configurations that provide solutions to the Walloon context by promoting niche markets, developing circular economy and reducing transport of supply feedstock. First, autonomous urban biorefineries are proposed, which use biological waste for the production of added value molecules and/or finished products and are energetically self-sufficient. Second,integrated urban biorefineries, which benefit from an energy supply from a nearby industrial activity. In the Walloon economic context, these types of urban biorefineries could provide solutions by promoting niche markets, developing a circular economy model, optimise the transport of supply feedstock and contribute to the sustainable development. [less ▲]

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See detailGenotype contribution to the chemical composition of banana rachis and implications for thermo/biochemical conversion
Tiappi Deumaga, Mathias Florian; Happi Emaga, Thomas; Tchokouassom, Raphael et al

in Biomass Conversion and Biorefinery (2015), 5(4), 409-416

Chemical composition of banana rachis from three varieties (Grande naine, Pelipita, and CRBP969) was ana- lyzed, and the genotype contribution to composition variabil- ity was investigated. Wet chemistry ... [more ▼]

Chemical composition of banana rachis from three varieties (Grande naine, Pelipita, and CRBP969) was ana- lyzed, and the genotype contribution to composition variabil- ity was investigated. Wet chemistry and instrumental analysis procedures (X-ray diffraction, 31P NMR spectroscopy, and thermogravimetry) were used. Some significant differences were found among the three genotypes: GN-AAA genotype was found to be significantly the highest in ash fraction (30.16 %) and the lowest in acid insoluble lignin (6.58 %) at 95 % confidence level. It showed also the highest content in potassium (43.5 % in ash). Implication of compositional dif- ferences on valorization efficiency by biochemical or thermo- chemical pathways was investigated. For this purpose, corre- lation coefficients between compositional characteristics and yields in volatile compounds from pyrolysis and glucose yields from enzymatic saccharification were analyzed. Ash content was revealed to be the main drawback parameter for volatile yields from pyrolysis (r = −0.93), while for glucose yields during saccharification were limited mainly by the con- tent in guaiacyl units of the lignin fraction (r = −0.98). How- ever, a strong and positive correlation was established be- tween the volatiles yield and the acid insoluble lignin content (r = 0.98) Thus, according to these observations and based on their compositional significant differences, GN-AAA was the better candidate for bioconversion pathway while PPT-ABB and CRBP969-AAAB samples were shown to be better can- didates for thermochemical conversion pathway. This work gives important preliminary information for considering ba- nana rachis as an interesting feedstock candidate for biorefinery. [less ▲]

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See detailProduction of biofuels and biobased compounds in urban biorefineries
Richel, Aurore ULg; Haubruge, Eric ULg

in Journal of Fundamental Renewable Energy and Applications (2015), 5(6), 93

“Urban biorefining” is an original concept aiming at using urban wastes (household wastes, municipal wastes, industrial liquid and or solid residues and side-products etc) mainly of vegetal origin for the ... [more ▼]

“Urban biorefining” is an original concept aiming at using urban wastes (household wastes, municipal wastes, industrial liquid and or solid residues and side-products etc) mainly of vegetal origin for the production of an array of biofuels and bio-products. This “urban bio-refining” concept fits particularly with the economic, geographic and politic contexts and constraints of the Walloon Region (south part of Belgium). Indeed, Walloon Region is a very small territory (area of about 6,504 sq mi) with a temperate climate. Supply feedstock mainly arising form forestry and agriculture are thus rather restricted, submitted to importation and subjected to non-standardized quality. Several examples of our regional strategy still available on an industrial scale are herein proposed and detailed. [less ▲]

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See detailProduction of biofuels and biobased compounds in urban biorefineries: A new paradigm for green chemistry
Richel, Aurore ULg; Haubruge, Eric ULg; Jacquet, Nicolas ULg

in Organic Chemistry Current Research (2015), 4(2), 88

Urban bio-refining is an original concept aiming at using urban wastes (household wastes, municipal wastes, industrial liquid and/or solid residues and side-products, etc.), mainly of vegetable origin ... [more ▼]

Urban bio-refining is an original concept aiming at using urban wastes (household wastes, municipal wastes, industrial liquid and/or solid residues and side-products, etc.), mainly of vegetable origin, for the production of an array of biofuels and bioproducts. This urban bio-refining concept fits particularly with the economic, geographic and politic contexts and constraints of the Walloon Region (south part of Belgium). Indeed, Walloon Region is a very small territory (area of about 6,504 sq mi) with a temperate climate. Supply feedstock, mainly arising from forestry and agriculture, are thus rather restricted, submitted to importation, and subjected to non-standardized quality. Several examples of our regional strategy, still available on an industrial scale, are herein proposed and detailed. [less ▲]

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See detailNon-alkaline solubilization of arabinoxylans from destarched wheat bran using hydrothermal microwave processing and comparison with the hydrolysis by an endoxylanase
Aguedo, Mario ULg; Ruiz, Héctor A.; Richel, Aurore ULg

in Chemical Engineering and Processing: Process Intensification (2015), 96

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See detailNon Digestible Oligosaccharides Modulate the Gut Microbiota to Control the Development of Leukemia and Associated Cachexia in Mice.
Bindels, Laure B.; Neyrinck, Audrey M.; Salazar, Nuria et al

in PloS one (2015), 10(6), 0131009

We tested the hypothesis that changing the gut microbiota using pectic oligosaccharides (POS) or inulin (INU) differently modulates the progression of leukemia and related metabolic disorders. Mice were ... [more ▼]

We tested the hypothesis that changing the gut microbiota using pectic oligosaccharides (POS) or inulin (INU) differently modulates the progression of leukemia and related metabolic disorders. Mice were transplanted with Bcr-Abl-transfected proB lymphocytes mimicking leukemia and received either POS or INU in their diet (5%) for 2 weeks. Combination of pyrosequencing, PCR-DGGE and qPCR analyses of the 16S rRNA gene revealed that POS decreased microbial diversity and richness of caecal microbiota whereas it increased Bifidobacterium spp., Roseburia spp. and Bacteroides spp. (affecting specifically B. dorei) to a higher extent than INU. INU supplementation increased the portal SCFA propionate and butyrate, and decreased cancer cell invasion in the liver. POS treatment did not affect hepatic cancer cell invasion, but was more efficient than INU to decrease the metabolic alterations. Indeed, POS better than INU delayed anorexia linked to cancer progression. In addition, POS treatment increased acetate in the caecal content, changed the fatty acid profile inside adipose tissue and counteracted the induction of markers controlling beta-oxidation, thereby hampering fat mass loss. Non digestible carbohydrates with prebiotic properties may constitute a new nutritional strategy to modulate gut microbiota with positive consequences on cancer progression and associated cachexia. [less ▲]

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See detailMediterranean agri-food processing wastes pyrolysis after pre-treatment and recovery of precursor materials: A TGA-based kinetic modeling study
Manara, Panagiota; Vamvuka, V; Sfakiotakis, S et al

in Food Research International (2015), 73

Valorization strategies of wastes from agri-food processes are intertwined with clean technological approaches and eco-industrial management. By-products from Mediterranean agri-food processes such as ... [more ▼]

Valorization strategies of wastes from agri-food processes are intertwined with clean technological approaches and eco-industrial management. By-products from Mediterranean agri-food processes such as olive oil, wine and fruit create a considerable disposal problem for the agro-industry. Their characteristics in combination with Mediterranean climate enhance microbial development and can be source of health and safety concerns. After pre-treatment and recovery of valuable precursor materials (lignin, pulp), pyrolysis can be used for fuels, chemicals and carbon bio-based materials production. Since thermal degradation kinetic studies are a key step for the efficient design of thermo-chemical processes, in this study pyrolysis experiments were performed, using TGA for the estimation of the process kinetic parameters. The independent parallel reaction model validat- ed against experimental results, showing a good agreement with experimental data, with deviation values rang- ing from 1.07 to 3.54%. [less ▲]

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See detailLes initiatives commerciales de bioraffinage en Région Wallonne: production de biocarburants et voies de valorisation connexes
Jacquet, Nicolas ULg; Desquay, Lucas ULg; Jadot, Bastien et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19(2), 197-203

Introduction Biorefining is progressively gaining interest in Wallonia as a complement to the conventional petrochemical industry. Biorefineries are categorized according to the nature of the raw ... [more ▼]

Introduction Biorefining is progressively gaining interest in Wallonia as a complement to the conventional petrochemical industry. Biorefineries are categorized according to the nature of the raw materials they treat (food or non-food) and the nature of their productions (energy and biofuels or biobased compounds). Literature Production of first-generation and second-generation biofuels (bioethanol and biodiesel) is described, as well as their parallel valorisation pathways. A description of the Belgian biobased industry is also provided. Conclusion Diversification of supply chains, as well as the need to promote a circular economy, becomes a priority for the development of biorefining in Wallonia. [less ▲]

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See detailApplication of Steam Explosion as Pretreatment on Lignocellulosic Material: A Review
Jacquet, Nicolas ULg; Maniet, Guillaume ULg; Vanderghem, Caroline ULg et al

in Industrial & Engineering Chemistry Research (2015), 54(10), 2593-2598

Steam explosion is a thermo-mechanicochemical pretreatment which allows the breakdown of lignocellulosic structural components by the action of heating, formation of organic acids during the process, and ... [more ▼]

Steam explosion is a thermo-mechanicochemical pretreatment which allows the breakdown of lignocellulosic structural components by the action of heating, formation of organic acids during the process, and shearing forces resulting in the expansion of the moisture. Two distinct stages compose the steam-explosion process: vapocracking and explosive decompression which include modification of the material components: hydrolysis of hemicellulosic components (mono- and oligosaccharides released), modification of the chemical structure of lignin, and modification of the cellulose crystallinity index, etc. These effects allow the opening of lignocellulosic structures and influence the enzymatic hydrolysis yield of the material. [less ▲]

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See detailMolécules issues de la valorisation de la lignine
Wertz, Jean-Luc; Richel, Aurore ULg; Gérin, Patrick

in ValBiom (2015), (Mars), 1-37

La valorisation de la lignine, dans le cadre de la bioraffinerie lignocellulosique du futur, est une thématique particulièrement prometteuse. En effet, la lignine est la principale matière première ... [more ▼]

La valorisation de la lignine, dans le cadre de la bioraffinerie lignocellulosique du futur, est une thématique particulièrement prometteuse. En effet, la lignine est la principale matière première renouvelable composée de motifs aromatiques. Ce polymère est le plus souvent valorisé uniquement par combustion dans les papeteries pour la production d’énergie. La mise en route de bioraffineries destinées à convertir la biomasse lignocellulosique en carburants de transport générera en général plus de lignine que nécessaire pour alimenter l’installation en énergie2. Dès lors, des efforts sont en cours pour transformer la lignine en produits à valeur ajoutée. Sa valorisation en composés aromatiques de bas poids moléculaires (tels que benzène, toluène, xylènes: BTX) permettrait une plus-value considérable dans la mesure où les BTX sont des molécules de base de la pétrochimie et représentent en 2015 un marché de 100 milliards de dollars3. On estime généralement que l’étude de la valorisation de la cellulose en particulier en éthanol a eu lieu il y a 20 ans, celle de la valorisation des hémicelluloses il y a 10 ans et celle de la valorisation de la lignine a lieu actuellement. [less ▲]

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See detailChemical composition and functional properties of dietary fibre extracted by Englyst and Prosky methods from the alga Ulva lactuca collected in Tunisia
Yaich, Hela; Garna, Haikel; Bchir, Brahim et al

in Algal Research (2015), 9

Nowadays there is a growing trend to find new sources of dietary fibre (DF), such as marine algae by-products that have traditionally been undervalued. In this respect, the aim of the present ... [more ▼]

Nowadays there is a growing trend to find new sources of dietary fibre (DF), such as marine algae by-products that have traditionally been undervalued. In this respect, the aim of the present investigation was firstly to compare two methods of dietary fibre quantification (Englyst and Prosky) and secondly to determine the chemical composition and some of the functional properties of total and insoluble fibres extracted in accordance with the Englyst method. The dietary fibres of dried Ulva lactuca collected from the Tunisian littoral were determined by the Prosky (gravimetric method) and Englyst (enzymatic-chemical method) methods. The two extraction methods (Englyst–Prosky) provided approximately the same values in total fibres (~54%). However, they had different insoluble and soluble fibre contents. U. lactuca contained 20.53% and 31.55% of soluble fibres and 34.37% and 21.54% of insoluble fibres using the Prosky and Englyst methods, respectively. The fractionation of the insoluble dietary fibre concentrate revealed that hemicellulose was the most abundant fraction (32.49%), followed by cellulose (16.59%) and “lignin-like” compounds (1.53%). For both fibre concentrates, the main neutral sugar was glucose (20.70%–27.59%), which corresponded to hemicellulose and cellulose. The water holding capacity of insoluble fibre concentrate was relatively high. It varied between 9.32 g and 10.3 g of water/g of dry fibre at 25 °C and 80 °C, respectively. Nevertheless, the oil holding capacity of the insoluble fibre concentrate was not affected by temperature. It was about 1.08 and 1.01 g of oil/g of dry fibre at 25 °C and 80 °C. Despite the significant functional properties of fibre concentrate, the presence of lead limits its use as an ingredient in the food industry. [less ▲]

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See detailOak barks as raw materials for the extraction of polyphenols for the chemical and pharmaceutical sectors: a regional case study
Dedrie, Maxime; Jacquet, Nicolas ULg; Bombeck, Pierre-Louis ULg et al

in Industrial Crops and Products (2015), 70

Despite their potential for chemical recycling, residues from forest harvesting and wood processing are mostly used for industrial applications with low added value (energy, paper pulp, panels). Bark of ... [more ▼]

Despite their potential for chemical recycling, residues from forest harvesting and wood processing are mostly used for industrial applications with low added value (energy, paper pulp, panels). Bark of both oak species, Quercus robur L. 1753, Quercus petraea (Matt.) Liebl. 1784 is a by-product from sawmill and pulp mill activities. Bark is mainly used as a fuel for the same wood plants. The aim of this study is to look at the feasibility of enhancing the value of this material through the extraction of bioactive molecules such as polyphenols (i.e. catechin, gallic and ellagic acids). First, the effect of industrial storage of logs and bark on their polyphenol content was explored. Then, referring to the selection of tan oaks in the past, the question of an optimum harvesting age is addressed in order to maximize the polyphenol content of the barks. In the end, molecular diversity of bark is examined through the identification of molecules of interest, using different chromatographic analyses. The results show an effect of the industrial context and an effect of the raw material age on the chemical properties of the bark. First investigations also highlight molecules of interest and the molecular diversity, which needs to be further explored. [less ▲]

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See detailMicrowave-assisted thermochemical and primary hydrolytic conversions of lignocellulosic resources: a review
Richel, Aurore ULg; Jacquet, Nicolas ULg

in Biomass Conversion and Biorefinery (2015), 5(1), 115-124

Faced with the inevitable depletion of fossil resources, agricultural productions have rapidly emerged as promising renewable alternatives. Particularly, the conversion of lignocellulosic materials has ... [more ▼]

Faced with the inevitable depletion of fossil resources, agricultural productions have rapidly emerged as promising renewable alternatives. Particularly, the conversion of lignocellulosic materials has nowadays opened new vistas for the production of energy, biofuels and chemicals. In this literature review, microwave technology is described as an original heating source either for the thermochemical conversions (at temperatures up to 400°C) of lignocellulose into biofuels or the pretreatment (below 400°C) and further hydrolysis of lignocellulose into bioethanol and other valuable chemicals. Advantages of microwave approaches include a commonly observed acceleration in reaction rate and improved selectivities and yields. [less ▲]

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See detailUse of wheat bran arabinoxylans in chitosan-based films: Effect on physicochemical properties
Costa, Maria J.; Cerqueira, Miguel A.; Ruiz, Héctor A. et al

in Industrial Crops and Products (2015), 66

tThe aim of this work was to evaluate physicochemical properties of chitosan-based films with differentfractions of arabinoxylans (AXs). Five fractions composed by AXs or mixtures of AXs and arabino-xylo ... [more ▼]

tThe aim of this work was to evaluate physicochemical properties of chitosan-based films with differentfractions of arabinoxylans (AXs). Five fractions composed by AXs or mixtures of AXs and arabino-xylo-oligosaccharides (AXOS) obtained through three different processes were added to chitosan-based films.These films were obtained by solvent casting and characterized in terms of water vapor permeability(WVP), opacity, thickness, moisture content and mechanical properties (i.e., tensile strength – TS andelongation at break – EB), being the chemical interactions evaluated by FTIR.Moisture content values ranged between 20 and 30% for all five studied films being the lowest valueobserved for chitosan films with the fraction F1 of AX/AXOS (21.1%). The films with incorporation of F3a,F3b and F4 AXs fraction were more opaque (>10%) than the other studied films. Regarding mechanicalproperties CH films presented EB and TS values of 31.26% and 8.25 MPa, respectively, both these valuesremain statistically equal with the incorporation of AX/AXOS except for films containing the fractionF1 and F2. For films with the F2 fraction were obtained higher values of EB (41.31%) while for CH filmscontaining the F1 fraction the TS values (13.07 MPa) increased.In conclusion, wheat bran AXs can be successfully incorporated into chitosan-based edible films pro-viding, together with chitosan, an extra functional value to films, due their health benefits. [less ▲]

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