Genetic analysis of organoleptic quality in fresh market tomato. 2. Mapping QTLs for sensory attributes

International audienc

Récupération de l'énergie électrique produite par les piles à combustibles microbiennes

Les Piles à Combustibles Microbiennes (PCMs) produisent de l'électricité à partir de la dégradation de matière organique par des bactéries. Pour récupérer l'énergie électrique produite, des architectures mettant en jeux plusieurs piles seront préférées à des architectures basées sur une pile unique de taille importante. Par ailleurs la nécessité d'élever les tensions, de mutualiser les puissances et d'adapter la charge à la source passent par le choix et le dimensionnement d'une chaîne judicieuse de convertisseurs de puissance spécifiques (faible tension d'entrée et basse puissance) au sein d'un réseau de PCMs. Le nombre de micro-sources considérées conduit naturellement à envisager la cellularisation de la conversion avec mise en réseau série et/ou parallèle des convertisseurs. Une récupération efficace de l'énergie passe également par l'intégration de la fonctionnalité MPPT (Maximum Power Point Tracking) qui permet d'adapter la charge à la pile

Contrôle génétique de la variation des teneurs en composés volatils chez la tomate

National audienc

Genetic analysis of organoleptic quality in fresh market tomato. 1. Mapping QTLs for physical and chemical traits

International audienc

FROM “OMICS” TO “OHMICS”: ELECTRICITYPRODUCING BACTERIAL COMMUNITY STRUCTURES IN MICROBIAL FUEL CELLS

International audienceMicrobial Fuel Cells (MFCs) are being developed as a novel biotechnology to harvest energy from dissolved organic matter with potential applications ranging from wastewater treatment to power sources for remote environmental sensors. To date, there is limited information about the structure of electro-active bacterial communities, and in order to optimize energy production in MFCs, a better understanding of these communities is essential. Our objective was to determine the taxonomic structure and spatial organization of the bacterial communities present at the surface of the electrodes during the formation and development of electro-active biofilms. Experiments were performed using single chamber MFCs fed with primary clarifier effluent from a municipal wastewater treatment plant. Community structure analyses were performed as a function of time and electrical performances using a combination of molecular tools (metagenomic DNA extraction, 16S-rRNA-based phylogenetic microarrays, pyrosequencing...). Analyses of the biofilm structure, distribution and physiological state of the bacterial cells at the surface of the electrodes were performed using a range of fluorochromes and epifluorescence microscopy equipped with a 3D imaging system. Metagenomic approaches helped us to identify putative bacterial species and genes involved in electricity production in MFCs. In combination with image analyses, data obtained strongly supports the possibility of increasing electrical performances by modifying electrode design, feeding and microbial growth conditions in MFCs

Cartographie moléculaire de la qualité organoleptique de la tomate. Perspectives d'utilisation des QTL

National audienc

STRUCTURE AND PERFORMANCE OF ELECTRO-ACTIVE BACTERIAL COMMUNITIES IN MICROBIAL FUEL CELLS UNDER VARYING OPERATING CONDITIONS

International audienceMicrobial Fuel Cells (MFCs) are being developed as a novel biotechnology to harvest energy from dissolved organic matter with potential applications ranging from wastewater treatment to power sources for remote environmental sensors. The objective of this work was to assess the role of operating conditions on the taxonomic structure and function (i.e., electricity production) of electro-active bacterial communities developing at the surface of the electrodes. Parameters tested included substrates (domestic wastewater, starch, glucose, acetate, lactate and LB medium), organic loads, feeding mode (batch and continuous mode) electrical conductivity of the system (open and close circuits), external resistances, and electrode composition and architecture. All experiments were performed using single chamber MFCs fed with primary clarifier effluent from a municipal wastewater treatment plant. Electrical performances (voltage, power) were determined throughout the different experiments. Community structure analyses were performed using RISA and 16S-rRNAbased phylogenetic microarrays. Results show that bacterial communities responsible for electricity production are markedly different from the inoculum (wastewater) and planktonic communities and from other compartments in the MFC. Communities are influenced by operating conditions and the presence of additional carbon sources, but remain relatively stable through time under given operating conditions. Correlations between bacterial community structure and substrates (nature and concentration) were observed, as well as between substrate concentration and electricity production. Interestingly, experiments conducted with different external resistances and with close and open circuits (i.e., electrons allowed to flow or not between the electrodes) showed the structure of electro-active bacterial communities is driven by electricity production

Cartographie moléculaire de facteurs de la qualité organoleptique des fruits en vue de leur utilisation en sélection

National audienc

QTLs for quality and flavour in fresh market tomatoes

International audienc