Search results for "mixture"
showing 10 items of 1178 documents
Chlorine flavor perception and neutralization in drinking water
2010
For water suppliers, using chlorine is necessary to ensure water bacteriological quality from the treatment plant to the consumers’ tap. However, chlorine flavour is one of the most common reasons advocated for choosing tap water alternatives as drinking water. As a consequence, the putative link between chlorine flavour perception and tap water consumption is an issue in drinking water habits studies. Since the sensory mechanisms involved in chlorine flavour perception remained largely unknown, the main objective of this thesis work was to first highlight those mechanisms and then to identify potential lever chlorine flavour sensory neutralisation.In a first step, we demonstrated that hypo…
Rules and Mechanisms of Perceptual Interaction of Odor Mixtures : Application to Icewine aroma
2021
Icewine was used as an experimental object, and hundreds of wine- or food-related odor mixtures were designed and investigated for the first time based on the identification and analysis of icewine’ odorants. The aim of the thesis work was to explore the key odor elements that affected the perception of odor mixtures and the general laws behind olfactory perceptual interactions. The thesis manuscript contains seven chapters:The first review of the literature gives a brief introduction to the olfactory system and odor perception. Then, odorants’ mixture perception is highlighted through examples of interactions between odorants at the perceptual level. Research progress in perceptual interac…
Microbial diversity and structure are drivers of the biological barrier effect against Listeria monocytogenes in soil
2013
International audience; Understanding the ecology of pathogenic organisms is important in order to monitor their transmission in the environment and the related health hazards. We investigated the relationship between soil microbial diversity and the barrier effect against Listeria monocytogenes invasion. By using a dilution-to-extinction approach, we analysed the consequence of eroding microbial diversity on L. monocytogenes population dynamics under standardised conditions of abiotic parameters and microbial abundance in soil microcosms. We demonstrated that highly diverse soil microbial communities act as a biological barrier against L. monocytogenes invasion and that phylogenetic compos…
Bacterial social networks across the French National territory
2017
EA SPE BIOME GENOSOL UB Agrosup EA SPE BIOME GENOSOL UB AgrosupEASPEBIOMEGENOSOL UB Agrosup; New generation sequencing evidenced that soil houses a huge microbial biodiversity. Based on these observations, it is now possible to better describe the spatial distribution of soil microbial communities, to study the ecological processes involved (environmental selection, dispersal limitations), and to compute the data to define the ecological attributes of soil microbial taxa. These huge datasets also offer the opportunity to study how soil microbial populations are interrelated. With this study, we revealed the first soil bacterial "social" network across French national territory based on 2,20…
Bacterial "social" network in french soils : a Metagenomics insight
2017
EA SPE BIOME GENOSOL UB Agrosup EA SPE BIOME GENOSOL UB AgrosupEASPEBIOMEGENOSOL UB Agrosup; New generation sequencing evidenced that soil houses a huge microbial biodiversity. Based on these observations, it is now possible to better describe the spatial distribution of soil microbial communities, to study the ecological processes lying behind (environmental selection, dispersal limitations), and to mine the data to define the ecological attributes of soil microbial taxa. These huge datasets also offer the opportunity to study how soil microbial populations are interrelated. The objective of this study was to design the first bacterial "social" network in french soils to characterize how b…
The significance of soil algae and cyanobacteria in agricultural soils, as a model of soil microbial communities, for the pesticide risk assessment
2017
The significance of soil algae and cyanobacteria in agricultural soils, as a model of soil microbial communities, for the pesticide risk assessment. 7ème Conference on Pesticide Behaviour in Soils, Water and Air
Effect of temperature on soil microbial structure and fractionation during C mineralisation
2008
International audience; Microbial carbon mineralization in soils leads to the production of different gaseous or dissolved components that have environmental impacts. Our study deals with the influence of soil temperature on the production of gaseous and dissolved carbon components during carbon mineralization in forest soils in France. After an incubation of soil samples for 42 days at 4 different temperatures, we determined both size and 13C isotopic signature of dissolved organic carbon and CO2 pools. We also characterised the soil microbial community structure (PLFA profiles). While temperature clearly increases the CO2 production, a low decrease of the dissolved organic carbon pool was…
Quantification of metal-resistant genes from the microbial community of uranium mine soils
2019
Background: Bacteria can thrive in environments presenting unique, extreme and/or stressful conditions, partly due to the diverse resistome they evolved as a result of physiological, metabolic and genetic adaptations. In this context, the microbial communities in soils from abandoned uranium mines may have peculiar genetic profiles that sustain valuable metal-resistance mechanisms. Getting further knowledge on the genetic potential of these microbial communities can be a contribute for developing bioremediation strategies towards the reclamation of highly contaminated uranium mine soils. Objectives: To quantify metal-resistance genes harboured by the microbial community of soil samples coll…
Characterization of the biosynthesis of saponins during seed development in peas (Pisum sativum)
2019
National audience; The use of pulses as ingredients for the production of food products rich in plant proteins is increasing. However, protein fractions prepared from pea or other pulses contain significant amounts of saponins, glycosylated triterpenes which can impart a bitter taste to the final food product. Bitter flavours are currently either removed by energy-requiring physico-chemical treatments or masked by additives. We are in the process of identifying and characterizing the genes involved in saponin biosynthesis during pea seed development, with the objective of identifying mutants in which seed saponins no longer accumulate. To do this we have applied a saponin extraction protoco…
Understanding the microbiological and physicochemical influence of alperujo vermicompost on diuron behaviour and soil quality
2009
Vermicompost as soil organic amendment increase the yield crops because improve the soil structure, the water retention capacity, the microbial biodiversity and thereby its metabolic activity. Vermicompost is also thought to reduce the pesticide pollution. The vermicompost selected was composed of “alperujo” which is largest organic residue in olive oil production. Agricultural soil was 5% amended twice and incubated for 3 months. A 3µg g-1 agricultural dosage of Diuron was applied to amended and unamended soils. The effect of alperujo vermicompost on dehydrogenase activity, the biodiversity and estimated bacterial density, the density of protocathechuate-degrading bacterial community and d…