Depuranat project: sustainable management of wastewater in rural areas

The Urban Wastewater Directive is aiming to implement adequate treatments of collected wastewater before 31 December 2005 in small communities with a population until 2000 equivalentinhabitant. Within the framework of the DEPURANAT project, co-financed by the European Interregional Cooperation Programme (Interreg IIIB Atlantic Arc), several Natural Reclamation Systems (NRS) based upon no-conventional technologies of wastewater treatment, have been studied from different points of view in rural areas: their effectiveness for producing regenerated wastewater of acceptable quality for several reuse options and vegetal biomass for different purposes, their environmental integration or their potential of implementation. Most of these treatment plants achieved high mean removal efficiencies: TSS (73–96%); BOD5 (74–94%); COD (53–90%); E. coli (2–3 log units); Enterococci (1.5–4 log units). The environmental impact of the systems was determined using an adapted life cycle assessment methodology and the economic analysis of the systems was focused on analysing the financial indicators, empirical cost functions, and the potential market for these technologies. Furthermore, maps of potential implementation of these systems and a support tool for deciding upon the installation of conventional or NRS were designed with the aim of promoting them.Communitary Interreg III-B Atlantic Area of EuropeDEPURANAT consortiu

Identification by Subtractive Hybridization of Sequences Specific for Salmonella enterica Serovar Enteritidis

Salmonella enterica serovar Enteritidis, a major cause of food poisoning, can be transmitted to humans through intact chicken eggs when the contents have not been thoroughly cooked. Infection in chickens is asymptomatic; therefore, simple, sensitive, and specific detection methods are crucial for efforts to limit human exposure. Suppression subtractive hybridization was used to isolate DNA restriction fragments present in Salmonella serovar Enteritidis but absent in other bacteria found in poultry environments. Oligonucleotide primers to candidate regions were used in polymerase chain reactions to test 73 non-Enteritidis S. enterica isolates comprising 34 different serovars, including Dublin and Pullorum, two very close relatives of Enteritidis. A primer pair to one Salmonella difference fragment (termed Sdf I) clearly distinguished serovar Enteritidis from all other serovars tested, while two other primer pairs only identified a few non-Enteritidis strains. These primer pairs were also useful for the detection of a diverse collection of clinical and environmental Salmonella serovar Enteritidis isolates. In addition, five bacterial genera commonly found with Salmonella serovar Enteritidis were not detected. By treating total DNA with an exonuclease that degrades sheared chromosomal DNA but not intact circular plasmid DNA, it was shown that Sdf I is located on the chromosome. The Sdf I primers were used to screen a Salmonella serovar Enteritidis genomic library and a unique 4,060-bp region was defined. These results provide a basis for developing a rapid, sensitive, and highly specific detection system for Salmonella serovar Enteritidis and provide sequence information that may be relevant to the unique characteristics of this serovar

Vulnérabilité, capabilité et rétablissement : un changement de modèle dans l’accompagnement psychologique.

International audienc

Detection of Salmonellae in Chicken Feces by a Combination of Tetrathionate Broth Enrichment, Capillary PCR, and Capillary Gel Electrophoresis

This report describes a rapid detection procedure for salmonellae from chicken feces by the combination of tetrathionate primary enrichment (preenrichment [PE])-bacterial lysis-capillary PCR and capillary gel electrophoresis. Pure Salmonella enterica serovar Enteritidis 64K was reisolated and detected by capillary PCR after buffered peptone water and nutrient broth, tetrathionate broth base Hajna (TTBH), and tetrathionate broth (TTB) preenrichments. When the same culture was mixed with intestinal homogenate, bacteriological reisolation and capillary PCR detection was achieved only by TTBH and TTB preenrichments. Capillary gel electrophoresis revealed that a Salmonella genus-specific 281-bp PCR product was detected when Salmonella strains but not non-Salmonella strains were tested. The detection limit of capillary PCR with whole-cell DNA extracted from pure Salmonella enterica serovars Enteritidis 64K, Typhimurium LT2-CIP60-62, and Gallinarum 64K was 3, 3, and 9 CFU ml(−1), respectively. The detection limit of capillary PCR from whole-cell DNA extracted from intestinal homogenate artificially contaminated with the same three strains was 3, 3, and 7 CFU ml(−1), respectively. We compared the results of the capillary PCR and bacteriological examination from the natural samples. Thirty-five of 53 naturally contaminated samples produced a specific PCR product. In 9 of the 35 PCR-positive samples, Salmonella could not be detected bacteriologically either by PE or a primary and delayed secondary enrichment (DSE) combination. In the 18 PCR-negative samples, 4 samples were found to harbor Salmonella by both PE and DSE and 14 samples were positive after DSE. Fifty-three additional intestinal homogenate samples, which were negative by their PE and DSE in bacteriological examination, were found to be also negative by their PCRs. The total time required to detect Salmonella with the capillary PCR method we used was approximately 20 h. If samples are from clinically diseased birds, the total time for PCR and detection is reduced to 2 h since the 18-h PE is not required. These results indicate that TTB enrichment, bacterial lysis, and genus-specific capillary PCR combined with capillary gel electrophoresis constitute a sensitive and selective procedure which has the potential to rapidly identify Salmonella-infected flocks