Anne-Marie Pourcher

Université de Bretagne Sud, Lorient, Brittany, France

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Publications (21)49.08 Total impact

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    ABSTRACT: A number of prokaryotes actively contribute to lignin degradation in nature and their activity could be of interest for many applications including the production of biogas/biofuel from lignocellulosic biomass and biopulping. This review compares the reliability and efficiency of the culture-dependent screening methods currently used for the isolation of ligninolytic prokaryotes. Isolated prokaryotes exhibiting lignin-degrading potential are presented according to their phylogenetic groups. With the development of bioinformatics, culture-independent techniques are emerging that allow larger-scale data mining for ligninolytic prokaryotic functions but today, these techniques still have some limits. In this work, two phylogenetic affiliations of isolated prokaryotes exhibiting ligninolytic potential and laccase-encoding prokaryotes were determined on the basis of 16S rDNA sequences, providing a comparative view of results obtained by the two types of screening techniques. The combination of laboratory culture and bioinformatics approaches is a promising way to explore lignin-degrading prokaryotes.
    Applied Microbiology and Biotechnology 10/2014; · 3.81 Impact Factor
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    ABSTRACT: The cultivation of microalgae with digestate supernatant is a promising process for the recovery of mineralized nutrients (P, N) from anaerobic digestion. Nevertheless, the variability of phosphorus concentration in the influent could limit this process. The impact of initial N:P ratios between 3 and 76 gN.gP-1 was studied and proved no growth limitation over 14-day batch experiments even when P was depleted. Nitrogen assimilation was not affected by phosphorus concentrations and reached 10.1 mgN.L-1.d-1 whereas phosphorus removal ranged from 0.6 to 2.0 mgP.L-1.d-1. The biomass N:P ratio was found to be a function of the influent N:P ratio. Phosphorus storage by microalgae was thus confirmed. Nitrification was found to be highly dependent on the initial phosphorus concentration. The evolution of microalgae communities was also monitored and revealed the advantage of Scenedesmus over Chlorella when the media was phosphorus-depleted.
    Bioresource Technology 10/2014; · 5.04 Impact Factor
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    ABSTRACT: During anaerobic digestion, nutrients are mineralized and may require post-treatment for optimum valorization. The cultivation of autotrophic microalgae using the digestate supernatant is a promising solution; however the dark color of the influent poses a serious problem. First, the color of the digestates was studied and the results obtained using three different digestates demonstrated a strong heterogeneity although their color remained rather constant over time. The digestates absorbed light over the whole visible spectrum and remained colored even after a ten-fold dilution. Secondly, the impact of light and of substrate color on the growth of Scenedesmus sp. and on nitrogen removal were assessed. These experiments led to the construction of a model for predicting the impact of influent color and light intensity on N removal. Maximum N removal (8.5 mgN-NH4+.L-1.d-1) was observed with an initial optical density of 0.221 and 244 μmolE.m-².s-1 light and the model allows to determine N removal between 15.9 and 22.7 mgN-NH4+.L-1.d-1 in real conditions according to the dilution level of the influent and related color. Changes in the microalgae community were monitored and revealed the advantage of Chlorella over Scenedesmus under light-limitation. Additionally microalgae outcompeted nitrifying bacteria and experiments showed how microalgae become better competitors for nutrients when phosphorus is limiting. Furthermore, nitrification was limited by microalgae growth, even when P was not limiting.
    Water Research 07/2014; 64:278-287. · 4.66 Impact Factor
  • Anne-Marie Pourcher, F. Picard, Romain Marti
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    ABSTRACT: The intensification of pig farming in Brittany has led to an increase flow of pollutants that can contaminate water. Effluent from farms on grates which represent about 90% of pig farms, cause chemical (nutrients, metals) and microbiological (pathogens) contamination. The transfer of nitrogen and phosphorus contribute to the eutrophication of surface waters. To apply the European directives on water quality, like the directive “nitrate”, a number of institutional and regulatory arrangements had been put in place to fight against the pollution of agricultural origin. Thus, it is possible to reduce nitrogen and phosphorus by adapting the feed to their physiological state. In areas with structural surpluses ofmanure treatment systems have been developed. It is more difficult to reduce concentrations of micro-organisms; they are able to survive through treatment. Treatments such as composting can significantly reduce the health risk. L’intensification des élevages porcins en Bretagne a engendré un accroissement des flux polluants susceptibles de contaminer les eaux. Les effluents produits par les élevages sur caillebotis qui représentent environ 90% des élevages de porcs, engendrent des contaminations chimiques (nutriments, éléments métalliques) et microbiologiques (germes pathogènes). Le transfert de l’azote et du phosphore contribuent ainsi à l’eutrophisation des eaux de surface. Relevant de directives européennes, des dispositifs d’ordre réglementaire ont été mis en place pour lutter contre la pollution d’origine agricole, à l’exemple de la directive “nitrate”. De nombreuses études ont été réalisées pour limiter les teneurs en polluants présents dans le lisier. Ainsi, il est possible de réduire l’azote et le phosphore en adaptant l’alimentation des animaux à leur stade physiologique. Dans les zones d’excédents structurels, des filières de traitement des lisiers ont été développées. IL est cependant plus difficile de réduire les concentrations en micro)organismes pathogènes, ceux-ci étant capables de survivre au travers des traitements. Seuls les traitements thermiques tels que le compostage permettent de diminuer significativement le risque sanitaire.
    Eau, milieux et aménagement, Une recherche au service des territoires, Edited by Aziz Ballouche, Aude Nuscia Taïbi, 03/2014: chapter Solutions mises en œuvre pour limiter la contamination des eaux par l’élevage porcin en Bretagne: pages p 135-148; Presses de l’Université d’Angers.
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    ABSTRACT: Fecal contaminations of inland and coastal waters induce risks to human health and economic losses. In order to improve water management, it is necessary to identify the sources of contamination, which implies the development of specific markers. In order to be considered as a valuable host-specific marker, one must (1) be source specific, (2) occur in high concentration in polluting matrices, (3) exhibit extra-intestinal persistence similar to fecal indicator bacteria (FIB) and (4) not grow out of the host. However, up to day no single marker has fulfilled all those criteria. Thus, it has been suggested to use a combination of markers in order to generate more reliable data. This has lead to the development of a Microbial Source Tracking (MST) toolbox including FIB and microbial and chemical specific markers in order to differentiate between human, bovine and porcine fecal contaminations. Those specific markers are, (1) genotypes of F-specific RNA bacteriophages, (2) bacterial markers belonging to the Bacteroidales (human-specific HF183, ruminant-specific Rum-2-Bac and pig-specific Pig-2-Bac markers), to the Bifidobacterium (Bifidobacterium adolescentis) and pig-specific Lactobacillus amylovorus, (3) fecal stanols and (4) caffeine. The development of this MST toolbox was composed of four steps, from the molecular scale to the watershed scale. At the molecular scale, the specificity and the concentration of those markers were studied in cattle and pig manures and in waste water treatment plant (WWTP) effluents and influents. At the microcosm scale, the transfer of bovine and porcine specific markers was investigated by rainfall simulations on agricultural plots amended with cattle or pig manure. Moreover, the relative persistence of FIB and human, porcine and bovine specific markers was investigated in freshwater and seawater microcosms inoculated with a WWTP influent, pig manure and cow manure. Finally, the aforementioned MST toolbox has been validated at the catchment scale by analysing three rivers impacted by fecal contaminations. The development and the application of this MST toolbox have highlighted (1) the specificity of the aforementioned markers, (2) their conservative transfer from soils to rivers and (3) their difference of persistence in seawater and in freshwater. Those results provide useful data in order to identify and manage fecal contaminations of superficial waters. In the case of single source contaminations, the markers provide coherent information: (1) the bovine or porcine markers were not detected in a river impacted by a WWTP effluent; (2) the occurrence of Rum-2-Bac and the distribution of stanols indicated a bovine contamination in a river flowing through cattle pasture. In the case of multiple source contaminations, the combination of markers is necessary to identify the main sources and the statistical treatment of the distribution of stanols could provide an approximation of their proportion.
    AGU Fall Meeting Abstracts; 12/2011
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    ABSTRACT: Since 2001 the swine experimental station of Guernévez has studied biological treatment plants for nutrient recovery and water recycling, suited to the fresh liquid manure coming out of flushing systems. An integrated system with continuous recycling was set up in 2007, associated with a piggery of 30 pregnant sows. It includes a screen, a vermifilter, and macrophyte ponds alternating with constructed wetlands. The screen and the vermifilter had a lower removal efficiency than in previous studies on finishing pigs. A settling tank was then added between the vermifilter and the first lagoon to collect the worm casts. A second vermifilter was added to recover this particulate organic matter. A storage lagoon was added to compensate for evaporative losses and complete pollution abatement, with goldfish as a bioindicator of water quality. The removal efficiency of the whole system was over 90% for COD and nitrogen, over 70% for phosphorus and potassium, and more than 4 logarithmic units for pathogens (E. coli, enterococci, C perfringens). Plant production was about 20 T DM ha(-1) y(-1). Floating macrophytes (Azolla caroliniana, Eichhornia crassipes, Hydrocotyle vulgaris) were more concentrated in nutrients than helophytes (Phragmites australis, Glyceria aquatica,…). Azolla caroliniana was successfully added to feed finishing pigs.
    Water Science & Technology 01/2011; 63(6):1314-20. · 1.10 Impact Factor
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    ABSTRACT: Fecal contamination of water resources is evaluated by the enumeration of the fecal coliforms and Enterococci. However, the enumeration of these indicators does not allow us to differentiate between the sources of fecal contamination. Therefore, it is important to use alternative indicators of fecal contamination to identify livestock contamination in surface waters. The concentration of fecal indicators (, enteroccoci, and F-specific bacteriophages), microbiological markers (Rum-2-bac, Pig-2-bac, and ), and chemical fingerprints (sterols and stanols and other chemical compounds analyzed by 3D-fluorescence excitation-matrix spectroscopy) were determined in runoff waters generated by an artificial rainfall simulator. Three replicate plot experiments were conducted with swine slurry and cattle manure at agronomic nitrogen application rates. Low amounts of bacterial indicators (1.9-4.7%) are released in runoff water from swine-slurry-amended soils, whereas greater amounts (1.1-28.3%) of these indicators are released in runoff water from cattle-manure-amended soils. Microbial and chemical markers from animal manure were transferred to runoff water, allowing discrimination between swine and cattle fecal contamination in the environment via runoff after manure spreading. Host-specific bacterial and chemical markers were quantified for the first time in runoff waters samples after the experimental spreading of swine slurry or cattle manure.
    Journal of Environmental Quality 01/2011; 40(3):959-68. · 2.35 Impact Factor
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    ABSTRACT: From preliminary researches on a pilot scale, a complete demonstration plant was built to treat the effluents of a 30 pregnant sow's piggery. It includes a screen, a vermifilter, a macrophyte lagooning, and a complementary water storage pond; the recycled water is used for flushing, and rainfall is collected to compensate for evapotranspiration. After functioning in 2008 and 2009, it was showed that, during the warm season, the whole plant produced an effluent suitable for flushing, where the concentration decrease was over 70% for the phosphorus and potassium, 95% for the COD and nitrogen, 99.8% for endocrine disruptors (estrogenic activity), and 99.99% for pathogenic micro-organisms. During the cold season, the dilution by the rain water and the treatment effect of the constructed wetlands lead to similar results. Nevertheless, for this season, suitable floating macrophytes that will cover the lagoons remain to be settled.
    11/2010;
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    ABSTRACT: Based on a comparison of the dominant microbial populations in 17 pig manure samples and using a molecular typing method, we identified a species, Lactobacillus sobrius and Lactobacillus amylovorus (which now are considered a single species and are designated L. sobrius/amylovorus here), that was consistently found in manure. The aim of the present study was to confirm by real-time PCR the relevance of this species as a marker of pig fecal contamination. The specificity of L. sobrius/amylovorus was evaluated in human and animal DNA extracted from feces. The real-time PCR assay then was applied to water samples, including effluents from urban wastewater treatment plants, runoff water, and rivers. L. sobrius/amylovorus was consistently present in all samples of swine origin: 48 fecal samples, 18 from raw manure and 10 from biologically treated manure at mean concentrations of 7.2, 5.9, and 5.0 log(10) cells/g, respectively. The species was not detected in any of the other livestock feces (38 samples from cattle and 16 from sheep), in the 27 human fecal samples, or in the 13 effluent samples from urban wastewater treatment plants. Finally, L. sobrius/amylovorus was not detected in runoff water contaminated by cattle slurry, but it was quantified at concentrations ranging from 3.7 to 6.5 log(10) cells/100 ml in runoff water collected after pig manure was spread on soil. Among the stream water samples in which cultured Escherichia coli was detected, 23% tested positive for L. sobrius/amylovorus. The results of this study indicate that the quantification of L. sobrius/amylovorus using real-time PCR will be useful for identifying pig fecal contamination in surface waters.
    Applied and Environmental Microbiology 03/2010; 76(5):1456-61. · 3.95 Impact Factor
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    ABSTRACT: Cattle and pig manure contain pathogenic micro-organisms which can be transferred to soil through land spreading and thence to surface water. Such faecal pollution may pose risks to human health. However, the bacteria currently monitored to assess faecal pollution (E. coli, faecal coliforms and enterococci) do not distinguish between faecal pollution of water from animal and human origin. The aim of this study was to develop chemical and microbiological tools and to compare their suitability to identify farm livestock sources of faecal contamination found in the environment. Four types of markers have been tested: (i) sitostanol/coprostanol and cholestanol/cholesterol steroids ratios, (ii) tryptophan / fulvic-like fluorescence ratio, (iii) F-specific RNA bacteriophages (genotypes I and IV) and (iv) bacterial markers belonging to the Bacteroidales (Rum-2-Bac and Pig-2-Bac) and to the species Lactobacillus amylovorus. We have searched for the presence of such markers in one river that was receiving effluent from a wastewater treatment plant, a second receiving effluent from a slaughterhouse and a third located in a cow pasture. We have also searched for such indicators in runoff waters collected after rainfall simulations on an agricultural plot previously landspread with either cattle or pig manure. The level of faecal contamination was estimated by the enumeration of E. coli. Sterol and stanol were characterized and quantified using a GC-MS method. Fluorescence properties of the samples were undertaken using fluorescence excitation-matrix spectroscopy. Bacteroidales and L. amylovorus were quantified using real-time PCR. F-specific RNA bacteriophages were enumerated following the ISO method. The distribution of the genotypes of F-specific RNA bacteriophages was examined by RT PCR. The results showed that none of the markers of contamination from animal manure were detected in the river contaminated by the urban effluent. Sitostanol/coprostanol and cholestanol/cholesterol steroids ratios and tryptophan/ fulvic-like fluorescence differentiated pig and cattle faecal contamination. Bacteriophages of genotypes I and IV, Bacteroidales Pig-2-Bac and L. amylovorus have been quantified in waters contaminated by pig manure whereas Bacteroidales Rum-2-Bac were present in water contaminated by cattle manure. The suitability of the proposed markers is demonstrated by their transfer via runoff to surface waters and their detection in contaminated water by animal faeces.
    14th Ramiran International Conference; 01/2010
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    ABSTRACT: The objective of this study was to identify fecal bacteria able to persist after wastewater treatment and that could be used as indicators of human fecal contamination. In a first step, the diversity of Bacteroidales, Clostridiaceae, Bifidobacterium, and Bacillus-Streptococcus-Lactobacillus cluster (BSL) was analysed using a fingerprint technique (CE-SSCP) and 16S rDNA libraries in waters collected at the end of the treatment process in different urban wastewater treatment plants. For each group, dominant bacteria present in most effluents were identified. Their origin (human feces, animal feces, non-fecal) was then analysed based on data of their closest relatives in public 16S rDNA databases. Among fecal bacteria recovered in the treated effluents analysed, phylotypes close to Bifidobacterium adolescentis and Bacteroides caccae seem to be specific to human beings. Phylotypes gathering only sequences of human fecal origin were also identified among the BSL and Clostridiaceae, two bacterial groups which have been poorly investigated for bacterial source-tracking purpose. Since these bacteria were detected post-treatment in most wastewater treatment plants, they may constitute potential new indicators of fecal contamination specific to humans that could be used to track fecal contamination of surface water by sewage.
    Water Research 11/2009; 44(6):1873-83. · 4.66 Impact Factor
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    Romain Marti, Patrick Dabert, Anne-Marie Pourcher
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    ABSTRACT: The objective of this study was to identify a microbial marker for pig manure contamination. We quantified the persistence of four dominant bacterial groups from the pig intestinal tract throughout manure handling at 10 livestock operations (including aerobic digestion) by using molecular typing. The partial 16S rRNA genes of Bacteroides-Prevotella, Eubacterium-Clostridiaceae, Bacillus-Streptococcus-Lactobacillus (BSL), and Bifidobacterium group isolates were amplified and analyzed by capillary electrophoresis single-strand conformation polymorphism. The most dominant bacterial populations were identified by cloning and sequencing their 16S rRNA genes. The results showed that Bifidobacterium spp. and, to a lesser extent, members of the BSL group, were less affected by the aerobic treatment than either Eubacterium-Clostridiaceae or Bacteroides-Prevotella. Two Bifidobacterium species found in raw manure were still present in manure during land application, suggesting that they can survive outside the pig intestinal tract and also survive aerobic treatment. The 16S-23S rRNA internal transcribed spacer of one species, Bifidobacterium thermacidophilum subsp. porcinum, was sequenced, and a specific pair of primers was designed for its detection in the environment. With this nested PCR assay, this potential marker was not detected in samples from 30 bovine, 30 poultry, and 28 human fecal samples or in 15 urban wastewater effluents. As it was detected in runoff waters after spreading of pig manure, we propose this marker as a suitable microbial indicator of pig manure contamination.
    Applied and Environmental Microbiology 07/2009; 75(15):4967-74. · 3.95 Impact Factor
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    ABSTRACT: Long term composting induces loss of C and organic matter stabilisation. These two processes may have opposite effects on long term carbon storage in soils. To check whether raw materials should be composted or not before being spread on the soil, changes in particle size fractions were quantified during composting of 9 tons of sewage sludge and straw. Both the mass of the fine fraction (<2 microm) and the amount of carbon contained in it increased after seven months, respectively, +37% and +43%. The fine fraction contributes to carbon sequestration. A literature review supported the assumption that composting should increase long term C storage. Nevertheless, soil texture or agricultural practices modify the behaviour of this fraction. Thus, the fractionation method used for soils is relevant to predict the effect of composting as a mitigation option in greenhouse gas reduction strategies, but is not sufficient in itself.
    Bioresource Technology 11/2008; 99(16):7636-43. · 5.04 Impact Factor
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    ABSTRACT: One concern in regard to the spreading of sewage sludge is the potential for contamination of soil and water by pathogens present in sludge. We studied the survival of enteric micro-organisms in sewage sludge following direct land-spreading. The sludge produced by a wastewater treatment plant (capacity equivalent to 2000 inhabitants; sludge storage tank of 700m3) was spread on a soil, at a rate of 80m3/ha. The tested micro-organisms included three of specific sanitary interest: faecal indicators, spores of Clostridium perfringens and enteroviruses. The results highlighted three types of behaviour associated with these three groups of micro-organisms. The enteroviruses were not detected 2 weeks after spreading on the soil whereas the concentration of faecal indicators fell slowly with an observed decrease of between 1.2 and 1.8logarithmic units over 2 months (but without the initial level of the soil being reached). Lastly, the concentrations of C. perfringens remained stable. The different survival times of the studied micro-organisms in soil, confirm the necessity to include several indicators (bacteria and viruses) to estimate reliably the sanitary risk related to sludge spreading.
    Applied Soil Ecology - APPL SOIL ECOL. 01/2007; 35(3):473-479.
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    ABSTRACT: The microbial community of a pig slurry on a farm was monitored for 6 months using both molecular and cultural approaches. Sampling was carried out at all the different stages of effluent handling, from the rearing build-up to slurry spreading. Total DNA of each sample was extracted and analyzed by PCR-single-strand conformation polymorphism (SSCP) analysis using primers targeting the 16S rRNA genes from the archaeal and bacterial domains and also the Eubacterium-Clostridium, Bacillus-Streptococcus-Lactobacillus, and Bacteroides-Prevotella groups. A comparison of the SSCP profiles showed that there were rapid changes in the dominant bacterial community during the first 2 weeks of anaerobic storage and that the community was relatively stable thereafter. Several bacterial populations, identified as populations closely related to uncultured Clostridium and Porphyromonas and to Lactobacillus and Streptococcus cultured species commonly isolated from pig feces, remained present and dominant from the rearing build-up to the time of spreading. Enumeration of fecal indicators (enterococci and Escherichia coli) performed in parallel using cultural methods revealed the same trends. On the other hand, the archaeal community adapted slowly during pig slurry storage, and its diversity increased. A shift between two hydrogenotrophic methanogenic Methanobrevibacter populations from the storage pit to the pond was observed. Microorganisms present in pig slurry at the time of spreading could not be detected in soil after spreading by either molecular or cultural techniques, probably because of the detection limit inherent in the two techniques.
    Applied and Environmental Microbiology 06/2006; 72(5):3578-85. · 3.95 Impact Factor
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    ABSTRACT: Enumeration and phenotypic characterization of aerobic cellulolytic bacteria were performed on fresh, 1 year old and 5 years old refuse samples of a French landfill site. Numbers of cellulolytic bacteria ranged from 1.1×106 to 2.3×108 c.f.u. (g dry wt.)−1 and were lower in 5 years old refuse samples. A numerical analysis of phenotypic data based on 80 biochemical tests and performed on 321 Gram-positive isolates from refuse, revealed a high phenotypic diversity of cellulolytic bacteria which were distributed into 21 clusters. Based on the phenotypic analysis and the sequencing of 16S rDNA of five representative strains of major clusters, the predominant cellulolytic groups could be assigned to the family of Bacillaceae and to the genera Cellulomonas, Microbacterium and Lactobacillus. Furthermore, chemical parameters such as pH, carbohydrates and volatile solid contents influenced the composition of the cellulolytic bacterial groups which were reduced essentially to the family of Bacillaceae in the oldest refuse samples.
    FEMS Microbiology Ecology 01/2006; 34(3):229 - 241. · 3.56 Impact Factor
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    ABSTRACT: Given the high level of background flora in sludge, methods for detecting Listeria monocytogenes are not well established. In this study, two critical parameters for the detection of L. monocytogenes were evaluated: the concentration of Listeria sp. in a modified Fraser broth (first stage of the method) and the proportion of L. monocytogenes on Palcam agar (second stage of the method). Concentrations of Listeria sp. estimated in 118 modified Fraser enrichment broths inoculated with four types of sludge, reached 10(4) bacteria per mL for 83% of the positive enrichment broths. Proportion of L. monocytogenes on Palcam agar, which was estimated by transferring all characteristic colonies of Listeria sp. onto Rapid'L Mono agar, was highly variable regardless of the type of sludge. According to these results, we proposed a protocol that consisted of an enrichment in modified Fraser broth for 48 h at 37 degrees C, followed by plating 0.1 mL of appropriate dilutions of broth onto Palcam agar. After an incubation of 48 h at 37 degrees C, a systematic identification of characteristic colonies of Listeria sp. on Rapid'L Mono agar allowed to enhance the detection of Listeria monocytogenes.
    Water Research 11/2003; 37(19):4810-4. · 4.66 Impact Factor
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    ABSTRACT: Malgré les importants efforts consentis ces dernières années pour limiter la contamination des eaux de surface (mise aux normes des stations d'épuration, des installations agricoles, traitements des effluents d'élevage...), leur qualité est encore insuffisante sur de nombreux sites et non conforme aux normes européennes. Les paramètres actuellement mesurés, Escherichia coli et entérocoques, sont susceptibles d'indiquer la présence de microorganismes pathogènes pour l'Homme sans toutefois indiquer leur origine (humaine ou animale). Depuis 2007, deux projets ("Traceurs" et Marquopoleau") qui réunissent une dizaine de partenaires ont pour objectif de proposer aux acteurs de l'eau des outils analytiques de différenciation de l'origine humaine ou animale d'une contamination fécale. Ces outils permettront in fine d'améliorer la qualité sanitaire des eaux de baignade par une augmentation de l'efficacité de la gestion des cas de non conformité, d'accéder à une maîtrise des risques sanitaires et de répondre aux nouvelles réglementations. Les projets regroupent 6 laboratoires de recherches dont les compétences complémentaires permettent de combiner deux approches : une approche microbiologique fondée sur l'identification de micro-organismes ayant des hôtes spécifiques et une approche chimique s'appuyant sur la détection de molécules de synthèse et de molécules naturelles spécifiquement humaines ou animales. Les outils analytiques que les laboratoires ont commencés à développer en 2007, reposent sur des méthodes de différenciation du génome bactérien et viral, sur des méthodes de chromatographie en phase gazeuse couplée à la spectrométrie de masse en tandem et sur la spectrométrie de fluorescence. La pertinence des marqueurs de contamination sera testée sur des eaux de surface recevant des rejets d'origine humaine ou animale bien caractérisés puis à l'échelle de bassins versants sur des eaux de baignade en eau douce et en eau de mer.
    1ères Rencontres nationales "Gestion des baignades en eau douce".
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    ABSTRACT: This study evaluated the impact of storing chicken manure on the degradation of enrofloxacin (ENR) and ciprofloxacin (CIP), and on the survival of CIP-resistant Enterobacteriaceae. At 24 d of age, half of 8900 chickens received ENR for 5 d. After the animals departed, their manure was stored in two heaps for 63 d. Enterobacteriaceae were cultured on media containing 0 to 32 mg L⁻¹ of CIP. A total of 320 isolates were fingerprinted using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) to evaluate community structure. Initial concentrations of ENR and CIP in the heap were 22 and 1.8 mg kg⁻¹, respectively. Seventy-three percent of the two fluoroquinolones were eliminated during storage. The administration of ENR led to a 5.1 log₋₁₀ decrease in Enterobacteriaceae concentrations and emergence of CIP-resistant bacteria, which became dominant in the feces. concentrations decreased 1.2 to 2.3 log₋₁₀ 2 d after the heaps were made and continued to decline during storage. No resistant were found by Day 63. The highest CIP minimum inhibitory concentration (MIC) values observed among isolates of and of both and sp. were 128 and 4 mg L⁻¹, respectively. The dominant ERIC-PCR profiles changed over time. There was no relationship between genotype and resistance-isolated strains to CIP. Storing chicken manure in heaps appeared to be an effective way of limiting the entrance of CIP-resistant E. coli into the environment but did not prevent the dissemination of fluoroquinolones after land spreading.
    Journal of Environmental Quality 41(3):754-63. · 2.35 Impact Factor
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    ABSTRACT: A wastewater treatment system including a screen, a vermifilter, macrophytes ponds, and constructed wetlands has been built after a pig housing on slatted-floor. The aims were, all at once, to recycle water for excretion washing and to produce, from the nutrients contained in the effluent, organic matter and plants that can be either sold or reused on the farm to reduce inputs. Analyses, made on the effluent at different steps of the treatment plant, show that the concentrations of the nitrogen, microorganisms and endocrine disruptors are drastically reduced, while the phosphorus and potassium removal go through the byproducts harvesting.
    Procedia Environmental Sciences. 9:130–139.