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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Purchasing Consortia of Transportation Services in Humanitarian Logistics

Merkx, Joost, Gresse, Philipp January 2012 (has links)
Purpose - The thesis aims to provide a framework of measuring the performance of pur-chasing consortia humanitarian sector. The performance measurement seeks to identify the competitive advantages of being a member of purchasing consortia during purchasing activities of transportation ervices. Design/methodology/approach – The research is based on a qualitative study with de-ductive and explanatory approach. Semi-structured interviews with experts within the humanitarian sector have been conducted to gain necessary and credible data. Findings – It has been identified that purchasing consortia do not mutually operate physical purchasing activities. However, the consortia performance measurement framework, derived from the resource-based view, illustrates that being a member gen-erates the capabilities of decreased purchasing complexity, learning capabilities and ca-pacity sharing. These capabilities have a significant impact on the purchasing process for transportation services and lead to the competitive advantages of (1) having access to extensive knowledge, (2) reducing operational efforts, (3) reducing lead-time and (4) improving learning procedures. Research limitations/implications – As the literature on humanitarian logistics is still in its infancy, further applications from the commercial sector were considered to strengthen the results of the framework. Practical implications - The extent of collaboration of purchasing consortia indicates that managers of HOs are able to gain significant expertise and offers advantageous opportunities in handling purchasing activities in humanitarian logistics. The implications cover strategic as well as operational issues. Originality/value – The thesis gives an insight about practical purchasing operations of existing consortia and detects previously unknown aspects within the literature of humanitarian logistics.
2

The consortium approach to employee assistance programs : a case study /

Solomons, Daniel D. January 1999 (has links)
Thesis (M.A.) -- Central Connecticut State University, 1999. / Thesis advisor: Dr. Marc Goldstein. "...in partial fulfillment of the requirements for the degree of Master of Arts in Psychology."
3

Degradation studies of 2, 4, 6, trinitrotoluene by a microbial consortia

Ortiz, Onofre 01 May 1997 (has links)
Microbial mats are natural heterotrophic and autotrophic communities dominated by cyanobacteria (blue-green algae). These constructed mats are durable, tolerant to a variety of toxins and resilient under changing environmental conditions. This research demonstrates that microbial mats provide an effective remediation treatment for 2,4,6 Trinitrotoluene (TNT) in water and soil. It showed that TNT is removed to undetectable limits after 5 days of treatment under any of the following conditions: light/dark; total light; total dark. This work also shows that in the presence of an inorganic material (lead), mats were able to remove both contaminants efficiently, thus making the microbial mat a good choice for mixed waste remediation. Kinetic studies performed during the first five hours of microbial treatment showed a pseudo first order reaction indicating that TNT removal is initially proportional to the concentration of TNT. The major metabolites detected after 24 hour of treatment were 4-amino-2,6- dinitrotoluene, 2-amino-4,6-dinitrotoluene, and 2,4-diamine-6-nitrotoluene. These metabolites have a toxicity level similar to TNT. However, mat extracts and growth medium concentrates taken after 24 hours treatment of TNT showed little or no toxicity. The lack of toxicity demonstrated by treated mat extracts and media concentrates suggest that these metabolites are not the final metabolic products. The chemical nature of these metabolites suggests that the chemical mechanism of biotransformation involves reduction of the nitro groups at the ortho and para position of the TNT structure. Results obtained from light and dark experiment suggest that photooxidation or photodegradation is not an important mechanism for degradation of TNT by mats. Results show that live mats likely degrade TNT via a biotransformation process. In comparison, heat killed mats show a much slower removal of TNT than live mats. TNT was the only species found in the water column and extracts of heat killed mats, which indicates that TNT is removed by a passive absorption process, but no evidence of biodegradation was observed.
4

Building bridges: a case study of the development and sustainability of an international partnership in post-secondary engineering education

Brolley, Margaret Elizabeth 22 December 2009 (has links)
In a world that is becoming increasingly globalized, a change in the nature of higher education is leading to increased collaboration across borders. In a sector once dominated by developed countries, developing countries are becoming larger players in providing education to their countries and expanding into the field of providing education for others. This partnership began in 1992 when Manitoba was experiencing reduced government funding, frozen tuition rates and declining student numbers while Malaysia was building the capacity of their higher education system. An inter-institutional partnership was established to create a mutually beneficial relationship between the Faculty of Engineering, University of Manitoba, and University College Sedaya International (UCSI) in Malaysia. This partnership was established with clear cut benefits to both parties and developed over time with close personal ties between the institutions. However, the partnership has been declining since 2003 when UCSI was permitted to grant degrees. The lifecycle of the partnership is examined in light of this structural change. Organization models of episodic change and punctuated equilibrium, and transformative learning theory are used to explain the status of the partnership and the options for its sustainability.
5

Building bridges: a case study of the development and sustainability of an international partnership in post-secondary engineering education

Brolley, Margaret Elizabeth 22 December 2009 (has links)
In a world that is becoming increasingly globalized, a change in the nature of higher education is leading to increased collaboration across borders. In a sector once dominated by developed countries, developing countries are becoming larger players in providing education to their countries and expanding into the field of providing education for others. This partnership began in 1992 when Manitoba was experiencing reduced government funding, frozen tuition rates and declining student numbers while Malaysia was building the capacity of their higher education system. An inter-institutional partnership was established to create a mutually beneficial relationship between the Faculty of Engineering, University of Manitoba, and University College Sedaya International (UCSI) in Malaysia. This partnership was established with clear cut benefits to both parties and developed over time with close personal ties between the institutions. However, the partnership has been declining since 2003 when UCSI was permitted to grant degrees. The lifecycle of the partnership is examined in light of this structural change. Organization models of episodic change and punctuated equilibrium, and transformative learning theory are used to explain the status of the partnership and the options for its sustainability.
6

Formuler des consortia microbiens pour piloter les propriétés sensorielles de gels à base de protéines de pois : Mieux comprendre l’effet de la matrice et des communautés microbiennes sur les propriétés sensorielles / Formulate microbial consortia to control the sensory properties of pea protein gels : Better understand the effect of matrix and microbial communities on the sensory properties

Ben Harb, Salma 18 December 2017 (has links)
Les systèmes alimentaires occidentaux ne sont pas durables en termes d‘impacts environnementaux et d‘effet sur la santé. Une solution est de revisiter les modes de consommation en favorisant les produits à base de protéines végétales. Cependant, un des verrous à l‘introduction des protéines végétales dans notre alimentation est leurs défauts sensoriels qui sont un frein à l‘acceptabilité des produits par les consommateurs. La fermentation est un procédé ancien qui pourrait être un levier à ce verrou sensoriel. Dans ce contexte, l‘objectif de ce projet de thèse est d‘étudier les bénéfices sensoriels apportés par la fermentation de gels enrichis en protéines végétales à l‘aide de consortia microbiens sélectionnés. Pour cela, une stratégie alliant analyses sensorielles, microbiologie et physicochimie a été mise en œuvre. Deux types de matrices contenant 10% de protéines et 10% d‘huile de colza ont été étudiés : la première est constituée de 100% de protéines de pois et la deuxième est constituée d‘un mélange de protéines de lait (50%) et de pois (50%). Sur la base des connaissances de la matrice et des propriétés fonctionnelles des micro-organismes, 56 souches microbiennes ont été sélectionnées. Une stratégie raisonnée d‘assemblage de ces souches a été mise en place, basée sur la répartition équilibrée selon leur groupe phylogénétique, mais aussi sur la connaissance experte des fonctions cibles aromatiques recherchées. En parallèle, plusieurs procédés de gélification ont été étudiés pour structurer les gels. Dans un premier temps, la fermentation a été étudiée sur des émulsions non gélifiées pour permettre la sélection des communautés microbiennes spécifiques pour chaque matrice. Dans un second temps, le potentiel d‘adaptation et de fonctionnement des écosystèmes sélectionnés ont été étudiés sur les émulsions gélifiées. La croissance et l‘abondance des microorganismes dans les gels après trois et sept jours de fermentation ont été évaluées sur milieu spécifique et le potentiel aromatique des consortia a été cartographié par un panel sensoriel.Dans une dernière partie du travail, les défauts/bénéfices sensoriels de la fermentation ont été étudiés de point de vue sensoriel et analytique. Les résultats montrent un fort potentiel d‘implantation des bactéries lactiques (principalement Lactobacillus plantarum, Lactobacillus rhamnosus, Lactococcus lactis et Lactobacillus casei) et de la majorité des eucaryotes (en particulier Mucor et Geotrichum) pour l‘émulsion mixte comme pour l‘émulsion végétale. Même si les souches appartenant aux groupes Actinobacteria et Proteobacteria ne soient pas compétitives vis-à-vis de la flore endogène (Bacillus), certaines espèces comme Hafnia alvei, Acinetobacter johnsonii et Glutamicibacter arilaitensis, ont montré une forte croissance quand elles sont inoculées en associations. Des notes aromatiques spécifiques pour chaque émulsion ont été générées permettant de masquer la note végétale « verte » caractéristique du pois. Ainsi, deux consortia ont pu être sélectionnés sur la base de notes lactiques et fruitées pour l‘émulsion végétale (VEGAN), et de notes fruitées pour l‘émulsion mixte (MEGAN). Le potentiel d‘adaptation de ces deux consortia dépendait de la composition et de la structure des gels. Ainsi, le consortium VEGAN semble bien adapté pour le gel végétal et génère des notes torréfiées/grillées, alors qu‘il génère des notes laitières (crème fraiche/caillé frais) dans le gel mixte. Le consortium MEGAN s‘implante très bien dans les deux types de gels, générant des notes fromagères et fruitées dans le gel mixte, mais ne permet pas de masquer les notes vertes dans le gel végétal. Les défauts sensoriels attribués aux notes vertes et à l‘amertume sont liés principalement à la présence des aldéhydes et des acides aminés hydrophobes respectivement, mais restent encore à approfondir. (suite et fin du résumé dans la thèse) / Western food systems are not sustainable in terms of environmental impacts and health effects. One solution is to revisit consumption patterns by favoring products based on plant proteins. However, one of the barriers to the introduction plant proteins in our diet is their sensory defects which can be obstacles for the acceptability of products by consumers. Fermentation is an ancient process that could be a solution to this sensory issue. In this context, the aim of this PhD thesis is to study the sensory benefits provided by the fermentation of plant protein-based gels using selected microbial consortia. In order to accomplish this, a strategy combining sensory analyzes, microbiology and physicochemistry was implemented. Two types of matrices containing 10% protein and 10% rapeseed oil were studied: the first consists of 100% pea protein and the second consists of a mixture of milk proteins (50%) and pea proteins (50%).Based on knowledge of the matrix and the functional properties of microorganisms, 56 microbial strains were selected. A reasoned strategy of assembly of these strains was put in place, based on the balanced distribution according to their phylogenetic group, but also on the expert knowledge of the desired aromatic functions. In parallel, several gelling processes were studied to structure the gels. In the first step, the fermentation was studied on non-gelled emulsions to allow the selection of specific microbial communities for each matrix. In the second step, the adaptation and functioning potential of the selected ecosystems were studied on gelled emulsions. The growth and abundance of microorganisms in the gels after three and seven days of fermentation were evaluated on a specific growing medium and the aromatic potential of the consortia was mapped by a sensory panel. In the final section of this study, the sensory defects / benefits of fermentation were studied from a sensorial and analytical point of view. The results show a highpotential for implantation of lactic acid bacteria and the majority of eukaryotes (in particular Mucor and Geotrichum) for the mixed emulsion and for the vegetable emulsion. Although strains belonging to the Actinobacteria and Proteobacteria groups are not competitive with endogenous flora (Bacillus), certain species such as Hafnia alvei, Acinetobacter johnsonii and Glutamicibacter arilaitensis, have shown strong growth when inoculated into associations. Specific aromatic notes for each emulsion were generated to mask the green note characteristic of peas. Thus, two consortia were selected on the basis of lactic and fruity notes for the vegetable emulsion (VEGAN), and fruity notes for the mixed emulsion (MEGAN). The adaptation potential of these two consortia depended on the composition and structure of the gel. Thus, the VEGAN consortium seems well suited for vegetable gels and generates roasted / grilled notes, while it generates dairy notes (fresh cream / fresh curd) in the mixed gels. The MEGAN consortium implements itself very well in both types of gels, generating cheesy and fruity notes in the mixed gel, but does not mask the green notes in the vegetable gels. The sensory defects attributed to green notes and bitterness are mainly related to the presence of aldehydes and hydrophobic amino acids respectively, but still need to be deepened. This study validated a proof of concept of formulation of fermented food products and will create opportunities for innovation.
7

[pt] AUTONOMIA, ACCOUNTABILITY E COESÃO INTERNA: UMA ANÁLISE POLÍTICO-INSTITUCIONAL DE CONSÓRCIOS INTERMUNICIPAIS / [en] AUTONOMY, ACCOUNTABILITY AND INTERNAL COHESION: A POLITIC-INSTITUCIONAL ANALYSIS OF INTERCITY CONSORTIA

RODRIGO CHALOUB DIEGUEZ 19 January 2012 (has links)
[pt] Os consórcios intermunicipais podem ser vistos como uma arena política federativa de cooperação horizontal, voltada para a produção compartilhada de decisões sobre políticas públicas. Nos últimos vinte anos, eles ganharam maior evidência, diante de um contexto no qual os municípios assumiram maiores responsabilidades na provisão de serviços sociais e execução de políticas públicas, e quando se fortaleceram como instrumento de gestão capaz de solucionar problemas que surgem de situações de interdependência entre os municípios e de casos em que a atuação regionalizada possibilita melhores condições de coordenação das ações entre os entes federativos. A dissertação analisa duas experiências de consorciamento no Estado do Rio de Janeiro, o Consórcio Intermunicipal de Saúde da Baixada Fluminense (CISBAF) e o Consórcio Intermunicipal Lagos São João (CILSJ). A metodologia de análise foi assentada sobre a autonomização institucional, a presença de mecanismos de controle democráticos e a vitalidade política em torno de uma coesão interna. A análise dos resultados obtidos identifica evidências de consolidação dos dois consórcios selecionados e indica diferenças entre os padrões institucionais do CISBAF e do CILSJ. Essas diferenças são explicadas (i) pela estratégia de coordenação e transferência de autoridade sobre a implementação e execução de políticas públicas dos governos federal e estadual em cada setor envolvido, (ii) pelas características da trajetória de cada caso, e (iii) pelos mecanismos que mantêm os municípios envolvidos e atraídos pela sua institucionalidade decisória. / [en] Intercity consortia may be seen as a federative political arena of horizontal cooperation, focused toward the shared production of policy decisions. In last twenty years, they have received growthing appreciation in context of a more active role for the municipalities on providing social services and policy-making. Furthermore, those arrangements become stronger as a management tool to solve problems of interdependence between the cities and when the regionalized activity enables better coordination of activities among the federal entities. The paper analysis two inter-municipal consortia in the State of Rio de Janeiro, Consórcio Intermunicipal de Saúde da Baixada Fluminense (CISBAF), that involves health policies, and Consórcio Intermunicipal Lagos São João (CILSJ), for environmental and water management. The analytical methodology was constructed based on institutional autonomy, presence of mechanisms of democratic control and maintenance of internal cohesion. The results indicates that the two cases are consistency experiences and identify some differences between their institutional patterns, which are explained by (i) the strategy of coordination and authority transfer over the policy-decision-making and policy-making, (ii) the path features in each case, and (iii) the mechanism used to keep the municipalities linked in the institucionalized decision proccess of the consortium.
8

Utilização de consorcio microbiano para biorremediação do meio ambiente contaminado com derivados de petroleo / The use of a microbial consortium for biorremediation of oil derivatives ¿ contaminated environment

Dias, Fabio Guimaro 07 November 2007 (has links)
Orientador: Lucia Regina Durrant / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-08T20:12:21Z (GMT). No. of bitstreams: 1 Dias_FabioGuimaro_D.pdf: 798649 bytes, checksum: c223f07173b848327e30607dc7f3fe6d (MD5) Previous issue date: 2007 / Resumo: Neste trabalho foi formulado um consórcio microbiano para avaliação de seu potencial em degradar petróleo e seus derivados, em microcosmos e meio mínimo de sais. As 43 bactérias testadas na primeira fase do projeto demonstraram alguma propriedade que as classificam como potencialmente degradadoras de hidrocarbonetos. Todavia, as cepas 1, 9, 22, 23 e 36 demonstraram os melhores e mais homogêneos resultados em praticamente todos os parâmetros analisados, sendo estas, portanto, as cinco cepas selecionadas para a formulação do consórcio. As cepas do consórcio propiciaram uma degradação média para todos os hidrocarbonetos testados de 62,65% para cepa 1, 61,12% para a cepa 9, 53,77% para a cepa 22, 57,87% para a cepa 23 e de 44,03% para a cepa 36. Com exceção de alguns HPA¿s degradados por determinadas cepas, a grande maioria não foi totalmente biodegradado, fato que pode ser comprovado pelos baixos valores de EC50, e, com isso, altos valores de toxicidade aguda. No experimento realizado em microcosmo, avaliando-se a evolução de C-CO2 por modelos estatísticos, pode-se concluir que a melhor condição para a maximização desse parâmetro foi na condição do ponto central para a fonte de nitrogênio (0,10 g/100g de solo), ferro (0,0015 g/100g de solo) e inóculo (0,6ml/100 g de solo) e, na condição de +2 para a fonte de fósforo (0,08 g/100g de solo). Com este experimento foram fixadas as condições ótimas para uma melhor evolução de CCO2 em solos contaminados. No mesmo experimento, analisando a degradação dos hidrocarbonetos por cromatografia gasosa, foi obtida uma melhor degradação para o experimento 3 (uréia 0,07 g/100g de solo, fosfato de potássio 0,065 g/100 g de solo, Sulfato de ferro 0,001 g/100 g de solo, e inoculo 0,4 ml/100 g de solo), com uma degradação de 70,74% dos hidrocarbonetos. Nos microcosmos utilizando solo da REPLAN (Refinaria de Paulínia/PETROBRAS), com histórico de contaminação, foi obtida uma melhor degradação para os hidrocarbonetos analisados de 75% quando se utilizou a bioestimulação e de 51,7% quando se utilizou a bioaumentação e bioestimulação juntas. Para os microcosmos utilizando o consórcio liofilizado, foi obtida uma degradação de 57,85% para o liofilizado sem nutriente e, de 67% para o liofilizado com nutriente. As linhagens foram identificadas através da técnica do RNA 16S, como sendo pertencentes a gênero Bacillus, exceto o microrganismo 23, cuja identificação não foi possível através dos resultados obtidos, o consórcio microbiano tem potencial para ser aplicado em áreas contaminadas com petróleo e seus derivados / Abstract: In this work, a microbial consortium was evaluated regarding to its potential to degrade oil and derivatives, using microcosms in salt minimal medium. Forty three bacteria were tested in the first phase of this project to demonstrate some properties that could identify them as potentially degraders of hydrocarbons. The strains 1, 9, 22, 23 and 36 showed the best and homogeneous results in practically all the analyzed parameters, and five strains were selected to be part of the bacterial consortium. These strains had an average degradation of 62.65% for the strain 1; 61.12% for the strain 9; 53.77% for the strain 22; 57.87% for the strain 23; and 44.03% for the strain 36. Some PAHs were not completelly degraded by some strains, and this fact could be proven by the low values of EC50, with production of high values of acute toxicidade. In the microcosm experiments, the C-CO2 evolution was performed using statistical models, which could be concluded that the best condition for the maximization of this parameter was in the central point condition for the nitrogen source (0.10g/100g of soil), iron (0.0015g/100g of soil) and inoculum (0,6ml/100g of ground), using the condition of +2 for the phosphorus source (0.08g/100g of soil). In this experiments could be set an excellent condition for a better evolution of C-CO2 in contaminated soil. In the same experiment, analyzing the degradation of the hydrocarbons in GC-FID, a better degradation was obtained for the experiment 3 (urea 0,07g/100g of soil, potassium fosfate 0.065g/100g of soil, iron sulphate 0.001g/100g of ground, and inoculum of 0.4 ml/100g of soil), reaching hydrocarbons degradation of 70.74%. In the microcosms using the REPLAN (PAULINIA REFINARY/PETROBRAS) soil with previous contamination history, the best degradation of 75% was promoted when bioestimulating, and 51.7% when this soil was bioaugmented with the bacterial consortium and also bioestimulated. For the microcosms using the lyofilizated consortium, a degradation of 57.85% was verifyed without nutrient, and 67% with nutrient. The strains were identified through the RNA 16S sequencing as Bacillus genus, excepting to the strain 23, whose results of sequencing identification was not possible in this time. These results showed that the microbial consortium has a potential application in contaminated areas with oil and derivatives / Doutorado / Doutor em Ciência de Alimentos
9

Cohorts and Consortia Conference: A Summary Report (Banff, Canada, June 17-19, 2009)

Boffetta, Paolo, Colditz, Graham A., Potter, John D., Kolonel, Laurence, Robson, Paula J., Malekzadeh, Reza, Seminara, Daniela, Goode, Ellen L., Yoo, Keun Young, Demers, Paul, Gallagher, Richard, Prentice, Ross, Yasui, Yutaka, O'Doherty, Kieran, Petersen, Gloria M., Ulrich, Cornelia M., Csizmadi, Ilona, Amankwah, Ernest K., Brockton, Nigel T., Kopciuk, Karen, McGregor, S. Elizabeth, Kelemen, Linda E. 01 March 2011 (has links)
Epidemiologic studies have adapted to the genomics era by forming large international consortia to overcome issues of large data volume and small sample size. Whereas both cohort and well-conducted case-control studies can inform disease risk from genetic susceptibility, cohort studies offer the additional advantages of assessing lifestyle and environmental exposure-disease time sequences often over a life course. Consortium involvement poses several logistical and ethical issues to investigators, some of which are unique to cohort studies, including the challenge to harmonize prospectively collected lifestyle and environmental exposures validly across individual studies. An open forum to discuss the opportunities and challenges of large-scale cohorts and their consortia was held in June 2009 in Banff, Canada, and is summarized in this report.
10

Développement d'une unité pilote de bioraffinerie permettant la mixogenèse en continu à partir de la biomasse non alimentaire via la fermentation anaérobie mésophile / Development of a biorefinery pilot permitting the continuous mixogenesis from non food biomass through mesophilic anaerobic fermentation

Pessiot, Jérémy 11 December 2014 (has links)
Les réserves de pétrole sont sur le déclin, les prix des ressources fossiles fluctuent et le CO 2 dégagé par leur consommation contribue inéluctablement au réchauffement climatique. Ce phénomène, conduit notre société vers l'utilisation accrue de biomasse pour la génération d'énergie, de composés chimiques et de matériaux. La réduction des déchets est considérée comme indissociable de cette transition énergétique et en opposition aux préjugés, l’accroissement des déchets organiques peut être bénéfique dans cette recherche de solutions alternatives. En effet, cela conduit à la génération de grandes quantités de matières qui peuvent représenter de potentielles ressources. De plus, changer le statut des déchets en coproduits pour la production de bioénergies n’entre pas en concurrence avec les filières alimentaires et cela constitue un des principaux enjeux des biotechnologies. Sous certaines conditions, les bioconversions anaérobies représentent des procédés d’ingénierie prometteurs pour accomplir le double enjeu de la valorisation des coproduits et de la production de molécules d’intérêt énergétique et chimique (biocarburants, chimie verte...). En revanche, l’innovation dans les biotechnologies blanches est nécessaire pour la production robuste, performante, rentable et environnementalement acceptable de biomolécules à partir de ressources renouvelables. Dans ce contexte, la société AFYREN a été pensée et créée pour répondre à ce défi mondial via sa technologie « tout en un », AFYNERIE, qui s’inspire de la nature et des sciences. L’objectif premier de ce travail de thèse, cœur du procédé AFYNERIE, était d’étudier les performances de microorganismes anaérobies, sous forme de souches pures ou de consortia pour la valorisation de substrats plus ou moins complexes via un processus de méthanogenèse avortée. Pour cela, il était nécessaire de considérer, déjà à l’échelle du laboratoire, une projection dans le monde industriel. Nous avons alors démontré les capacités de la diversité microbienne à produire des molécules plateformes à partir de coproduits agro-industriels réels en mode stérile puis non stérile. Cette étude s’est appuyée en parallèle sur la caractérisation et la dynamique des populations microbiennes mises en jeu. Ensuite, l’accumulation des métabolites, à la fois inhibiteurs et d’intérêt, dans les milieux fermentaires en mode discontinu et avec des rendements compétitifs, a débouché sur la nécessité de surpasser ces limitations par le passage à un mode continu. Pour ce faire, un procédé d’extraction biocompatible des synthons issus de l’opération de fermentation a été mise en œuvre selon différents mode de réalisations. Ce couplage des opérations unitaires, sous forme de fermentation extractive, a livré des résultats prometteurs tout en étant bâtit dans un cadre de bioraffinerie et d’écologie industrielle qui tend vers le « zéro déchet ». Enfin, à l’inverse des autres technologies émergentes, pour se placer dans une approche de drop-in, la biologie et la chimie ont été associées. Le but a été d’illustrer la multipotence des acides gras volatils (AGVs) en termes d’applications industrielles et de réaliser la preuve de concept de la transformation de la biomasse non alimentaire en biomolécules d’intérêt énergétique et chimique. Ces travaux ont permis de soulever les points clés du changement d’échelle du procédé AFYNERIE et d’entrevoir des perspectives tant fondamentales qu’appliquées. Cette brique technologique, de par sa philosophie multi-intrants/multi-produits, couplant fermentation-extraction-synthèse, permet d’initier la transition au stade pilote d’un procédé innovant compatible avec une future économie biosourcée. / Fossil oil reserves are decreasing, oil prices are fluctuating, and the CO 2 released by oil consumption contributes to global warming. These are driving our society towards increased use of biomass for energy, chemical compounds and other materials. Minimizing waste has been seen as a concern associated with alternative energy efforts. Contrary to expectation, increasing organic waste can be beneficial for alternative energy efforts, because it would result in large amounts of organic resources that can be potential raw materials. Moreover, using waste as a resource for bioenergy production does not compete with human or animal food or agricultural surfaces, and that is one of the greatest challenges facing biotechnology. Using waste as a resource for biomolecule production would thus be an interesting approach to reducing waste in the environment and producing renewable materials. Under specific conditions, detrital biomass can be converted into biomolecules of interest by microorganisms. Anaerobic fermentation techniques represent promising engineering processes for accomplishing the dual goals of waste reduction and renewable biomolecule production for biofuel and green chemistry markets. On the other hand, innovative fermentation processes are necessary for the strong, successful, cost-effective and eco-friendly production of bulk chemicals from renewable resources. In this context, AFYREN company was thought and founded to answer this world challenge through its “all in one” technology, AFYNERIE, which is inspired from the nature and sciences. The first objective of this thesis, heart of the AFYNERIE process, was to study the performances of anaerobic microorganisms, in the form of pure strains or of consortia for the valorization of more or less complex substrata via a process of failed methanogenesis. For that purpose, it was necessary to consider, already at the laboratory scale, a projection in the industrial world. Then, we demonstrated the capacities of the microbial diversity to produce platform molecules from real agro-industrial by-products in sterile and then non sterile mode. This study leaned in parallel on the characterization and the dynamics of involved microbial populations. Then, the accumulation of metabolites, which are at the same time inhibitory and of interest, in fermentative media in batch mode and with competitive yields, resulted in the necessity of surpassing these limitations by the passage in a continuous mode. To do this, a process consisted of a biocompatible extraction of synthons stemming from the operation of fermentation was implemented according to different mode of realizations. This coupling of single operations, in the form of extractive fermentation, delivered promising results while builds in a frame of biorefinery and industrial ecology which tightens towards a “zero waste”. Finally, contrary to the other emergent technologies, to take place in a drop-in approach, biology and chemistry were associated. The purpose was to illustrate the versatility of volatile fatty acids (VFAs) in terms of industrial applications and to realize the proof of concept of the transformation of the non-food biomass in biomolecules of energy and chemical interest. These works allowed to underline key points of the scale-up of AFYNERIE process and to glimpse perspectives fundamental as well as applied perspectives. This technological brick, due to its multi-inputs / multi-products philosophy, coupling fermentation-extraction-synthesis, allows to introduce the transition to the pilot stage of an innovative process compatible with a future biobased economy.

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