scholarly journals Removal and relationships of microbial indicators in a water treatment and reclamation facility

2012 ◽  
Vol 10 (4) ◽  
pp. 549-556 ◽  
Author(s):  
Laura Alcalde ◽  
Montserrat Folch ◽  
Josefina C. Tapias
Keyword(s):  
Escherichia Coli ◽  
Wastewater Treatment ◽  
Water Treatment ◽  
The Other ◽  
Bacterial Indicators ◽  
Microbial Indicators ◽  
Indicator Microorganisms ◽  
E Coli ◽  
North East

A wastewater treatment and reclamation facility in north-east Spain was monitored over 1 year to determine the occurrence and concentrations of different microbial indicators (Escherichia coli, fecal enterococci, somatic bacteriophages and spores of sulfite-reducing clostridia). The removal of the indicators and its relationships through the wastewater treatment and reclamation trains were evaluated. The results obtained show that the reclamation treatments evaluated present a different efficiency in indicator microorganisms' removal depending on the type of microorganism. The E. coli and enterococci present an average reduction slightly higher than the other indicators, followed by somatic bacteriophages and spores of sulfite-reducing clostridia. The Spearman's correlations indicate that it is not suitable to use any of the bacterial indicators evaluated to predict the content of virus or spores of sulfite-reducing clostridia. Therefore, in order to evaluate the microbiological risk of the reclaimed effluent use, it is necessary to monitor the three types of indicator microorganisms (bacteria, virus and protozoa).

Hygiene Indicator Microorganisms for Selected Pathogens on Beef, Pork, and Poultry Meats in Belgium

2008 ◽  
Vol 71 (1) ◽  
pp. 35-45 ◽  
Author(s):  
Y. GHAFIR ◽  
B. CHINA ◽  
K. DIERICK ◽  
L. DE ZUTTER ◽  
G. DAUBE
Keyword(s):  
Escherichia Coli ◽  
Sampling Method ◽  
Baseline Data ◽  
Bacterial Indicators ◽  
Indicator Microorganisms ◽  
E Coli ◽  
Layer Chicken ◽  
Skin Excision ◽  
Pig Carcasses ◽  
The Relationship

Several bacterial indicators are used to evaluate hygiene during the meat slaughtering process. The objectives of this study were to assess the Belgian baseline data on hygienic indicators and the relationship between the indicators and zoonotic agents to establish hygiene indicator criteria for cattle, pig, and chicken carcasses and meat. The study used the results from the official Belgian surveillance plan from 2000 to 2003, which included the monitoring of Escherichia coli counts (ECC), Enterobacteriaceae counts (EC), aerobic colony counts (ACC), and Pseudomonas counts (PC). The sampling method was the wet and dry swabbing technique for cattle and pig carcasses and neck skin excision for broiler and layer chicken carcasses. The 75th and 95th percentiles of ECC were −0.20 and 0.95 log CFU/cm2 for cattle carcasses, 1.20 and 2.32 log CFU/cm2 for pig carcasses, and 4.05 and 5.24 log CFU/g for chicken carcasses. The ACC were 2.1- to 4.5-log higher than the ECC for cattle, pigs, and chickens. For cattle and pig carcasses, a significant correlation between ECC, EC, and ACC was found. ECC for pork and beef samples and EC in pig carcasses were significantly higher in samples contaminated with Salmonella. In poultry samples, ECC were in general higher for samples containing Salmonella or Campylobacter. Thus, E. coli may be considered as a good indicator for enteric zoonotic agents such as Salmonella for beef, pork, and poultry samples and for Campylobacter in poultry samples.

scholarly journals Escherichia coli O157:H7 SURVIVAL IN TRADITIONAL AND LOW LACTOSE YOGURT DURING FERMENTATION AND COOLING PERIODS

2017 ◽  
Vol 18 (0) ◽  
Author(s):  
Camila Sampaio Cutrim ◽  
Raphael Ferreira de Barros ◽  
Robson Maia Franco ◽  
Marco Antonio Sloboda Cortez
Keyword(s):  
Escherichia Coli ◽  
The Other ◽  
Lactose Hydrolysis ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Gas Formation ◽  
Whole Milk ◽  
Milk Contamination ◽  
Different Types ◽  
Fermentation Period

Abstract The purpose of this study was to evaluate the behavior of E. coli O157:H7 during lactose hydrolysis and fermentation of traditional and low lactose yogurt. It also aimed to verify E. coli O157:H7 survival after 12 h of storage at 4 ºC ±1 ºC. Two different types of yogurts were prepared, two with whole milk and two with pre-hydrolyzed whole milk; in both groups one yogurt was inoculated with E. coli O157:H7 and the other one was not inoculated. The survival of E. coli and pH of yogurt were determined during fermentation and after 12-h refrigeration. The results showed that E. coli O157:H7 was able to grow during the fermentation period (from 4.34 log CFU.mL-1 to 6.13 log CFU.mL-1 in traditional yogurt and 4.34 log CFU.mL-1 to 6.16 log CFU.mL-1 in low lactose yogurt). The samples with E. coli O157:H7 showed gas formation and syneresis. Thus, E. coli O157:H7 was able to survive and grow during fermentation of traditional and low lactose yogurts affecting the manufacture technology. Moreover, milk contamination by E. coli before LAB addition reduces the growth of L. bulgaricus and S. thermophilus especially when associated with reduction of lactose content.

Removal improvement of bacteria (Escherichia coli and enterococci) in maturation ponds using baffles

2012 ◽  
Vol 65 (4) ◽  
pp. 589-595 ◽  
Author(s):  
A. Ouali ◽  
H. Jupsin ◽  
J. L. Vasel ◽  
L. Marouani ◽  
A. Ghrabi
Keyword(s):  
Escherichia Coli ◽  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
E Coli ◽  
Conventional Activated Sludge ◽  
In Series ◽  
Hydrodynamic Study ◽  
Rhodamine Wt ◽  
Engineering Intervention

Korba wastewater treatment plant is a conventional activated sludge followed by three maturation ponds (MP1, MP2, MP3) in series acting as a tertiary treatment. The first study of wastewater treatment plants showed that the effluent concentration of Escherichia coli and enterococci at the outlet of the (MP3) varies between 103 and 104CFU/100 ml. After the hydrodynamic study conducted by Rhodamine WT which showed short-circuiting in the MP1, two baffles were introduced in the first maturation pond (MP1) to improve the hydrodynamic and the sanitary performances. The second hydraulic study showed that the dispersion number ‘d’ was reduced from 1.45 to 0.43 by this engineering intervention and the Peclet number was raised from 0.69 to 2.32. The hydraulic retention time was increased by 14 h. Because of well-designed baffles, the removal efficiency of E. coli and enterococci was raised between 0.2 and 0.7 log units for the first maturation pond.

Distribution of Coliphages in Various Foods

1986 ◽  
Vol 49 (12) ◽  
pp. 944-951 ◽  
Author(s):  
J. E. KENNEDY ◽  
C. I. WEI ◽  
J. L. OBLINGER
Keyword(s):  
Escherichia Coli ◽  
Food Samples ◽  
Fecal Coliforms ◽  
Bacterial Indicators ◽  
Processed Meats ◽  
E Coli ◽  
Plate Counts ◽  
The Relationship

The distribution of coliphages in various foods and the relationship between the incidences of coliphages and bacterial indicators were investigated. A total of 120 food samples comprising twelve products and including fresh meats, shellfish, vegetables and processed meats, were analyzed for indigenous coliphages using Escherichia coli hosts C, C-3000 and B. Bacterial analyses included enumeration of E. coli, fecal coliforms and coliforms, as well as aerobic plate counts and Salmonella analyses. Coliphages were detected (≥10 PFU/100 g) in 56% of samples and eleven of twelve products. Coliphages, E. coli, fecal coliforms and coliforms were recovered at a level of at least 30 organisms per 100 g in 43, 43, 68 and 81% of samples, with overall mean recoveries of 13, 19, 93 and 4300 organisms/100 g, respectively. Highest and lowest recoveries of coliphages and E. coli were from fresh meats and vacuum-packaged processed meats, respectively. Significant nonparametric correlations between coliphages, E. coli, fecal coliforms and coliforms were found among all food samples.

scholarly journals  Faecal shedding of verotoxigenic Escherichia coli in cattle in the Czech Republic

2011 ◽  
Vol 56 (No. 4) ◽  
pp. 149-155 ◽  
Author(s):  
P. Alexa ◽  
L. Konstantinova ◽  
Z. Sramkova-Zajacova
Keyword(s):  
Escherichia Coli ◽  
Czech Republic ◽  
Dairy Cattle ◽  
Age Groups ◽  
Immunomagnetic Separation ◽  
The Other ◽  
Somatic Antigen ◽  
The Czech Republic ◽  
E Coli ◽  
One Year

A survey to estimate the prevalence of verotoxigenic E. coli (VTEC) or enterohaemorrhagic E. coli (EHEC) in rectal swabs from healthy dairy cattle aged three weeks, three months and one year was conducted in three herds from the Czech Republic. Screening for the presence of the stx1, stx2 and eaeA genes in faecal swab cultures was performed by PCR, and in positive samples, isolated colonies were examined. Immunomagnetic separation was used for the isolation of the VTEC serogroup O157 from samples. VTEC were detected in animals from all three herds under study. In the group of 3-week-old calves, VTEC were only detected in samples collected in the summer months. However, in the other age-groups, VTEC were detected in both the summer and winter months. EHEC shedding was observed in 30 to 100% of the total samples collected from cattle aged three months and one year in the summer months, and in 30 to 60% of samples taken in the winter months. EHEC strains of serogroup O157 were detected in two herds. The range of verotoxins shed by VTEC isolates of serogroup O157 differed between herds. Besides serogroup O157, additional EHEC belonging to the antigen groups O26, O103, O128 and O153 have been identified, and in some of them, no somatic antigen was detected.

scholarly journals Shedding of Escherichia coli O157:H7 in Dairy Cattle Housed in a Confined Environment following Waterborne Inoculation

2002 ◽  
Vol 68 (4) ◽  
pp. 1947-1954 ◽  
Author(s):  
J. A. Shere ◽  
C. W. Kaspar ◽  
K. J. Bartlett ◽  
S. E. Linden ◽  
B. Norell ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Water Treatment ◽  
Gel Electrophoresis ◽  
Pulsed Field Gel Electrophoresis ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Bull Calves ◽  
Genomic Dnas ◽  
Confined Environment ◽  
Effective Water

ABSTRACT A study of Escherichia coli O157:H7 transmission and shedding was conducted with bull calves housed in individual pens within a confined environment. For comparative purposes, the numbers and duration of E. coli O157:H7 shedding in naturally infected calves were monitored after a single purchased calf (calf 156) tested positive prior to inoculation. During the next 8 days, the calves in adjacent pens and a pen directly across a walkway from calf 156 began to shed this serotype O157:H7 strain. Five of the eight calves in this room shed this O157:H7 strain at some time during the following 8 weeks. The numbers of E. coli O157:H7 isolates shed in these calves varied from 60 to 105 CFU/g of feces, and the duration of shedding ranged from 17 to >31 days. The genomic DNAs from isolates recovered from these calves were indistinguishable when compared by using XbaI digestion and pulsed-field gel electrophoresis. Inoculation of calves with 1 liter of water containing ca. 103 to 104 CFU of E. coli O157:H7/ml resulted in shedding in 10 of 12 calves (trial 1, 4 of 4 calves; trial 2, 6 of 8 calves). The inoculated calves shed the inoculation strain (FRIK 1275) as early as 24 h after administration. The duration of shedding varied from 18 to >43 days at levels from 102 to 106 CFU/g of feces. The numbers of doses necessary to initiate shedding varied among calves, and two calves in trial 2 never shed FRIK 1275 after four doses (ca. 106 CFU per dose). Results from this study confirm previous reports of animal-to-animal and waterborne dissemination of E. coli O157:H7 and highlight the need for an effective water treatment to reduce the spread of this pathogen in cattle.

scholarly journals Extraintestinal Pathogenic and Antimicrobial-Resistant Escherichia coli, Including Sequence Type 131 (ST131), from Retail Chicken Breasts in the United States in 2013

2017 ◽  
Vol 83 (6) ◽  
Author(s):  
James R. Johnson ◽  
Stephen B. Porter ◽  
Brian Johnston ◽  
Paul Thuras ◽  
Sarah Clock ◽  
...  
Keyword(s):  
United States ◽  
Escherichia Coli ◽  
Virulence Genes ◽  
Meat Products ◽  
The United States ◽  
Sequence Type ◽  
The Other ◽  
Antibiotic Resistant ◽  
Content Type ◽  
E Coli

ABSTRACT Chicken meat products are hypothesized to be vehicles for transmitting antimicrobial-resistant and extraintestinal pathogenic Escherichia coli (ExPEC) to consumers. To reassess this hypothesis in the current era of heightened concerns about antimicrobial use in food animals, we analyzed 175 chicken-source E. coli isolates from a 2013 Consumer Reports national survey. Isolates were screened by PCR for ExPEC-defining virulence genes. The 25 ExPEC isolates (12% of 175) and a 2:1 randomly selected set of 50 non-ExPEC isolates were assessed for their phylogenetic/clonal backgrounds and virulence genotypes for comparison with their resistance profiles and the claims on the retail packaging label (“organic,” “no antibiotics,” and “natural”). Compared with the findings for non-ExPEC isolates, the group of ExPEC isolates had a higher prevalence of phylogroup B2 isolates (44% versus 4%; P < 0.001) and a lower prevalence of phylogroup A isolates (4% versus 30%; P = 0.001), a higher prevalence of multiple individual virulence genes, higher virulence scores (median, 11 [range, 4 to 16] versus 8 [range, 1 to 14]; P = 0.001), and higher resistance scores (median, 4 [range, 0 to 8] versus 3 [range, 0 to 10]; P < 0.001). All five isolates of sequence type 131 (ST131) were ExPEC (P = 0.003), were as extensively resistant as the other isolates tested, and had higher virulence scores than the other isolates tested (median, 12 [range, 11 to 13] versus 8 [range, 1 to 16]; P = 0.005). Organic labeling predicted lower resistance scores (median, 2 [range, 0 to 3] versus 4 [range, 0 to 10]; P = 0.008) but no difference in ExPEC status or virulence scores. These findings document a persisting reservoir of extensively antimicrobial-resistant ExPEC isolates, including isolates from ST131, in retail chicken products in the United States, suggesting a potential public health threat. IMPORTANCE We found that among Escherichia coli isolates from retail chicken meat products purchased across the United States in 2013 (many of these isolates being extensively antibiotic resistant), a minority had genetic profiles suggesting an ability to cause extraintestinal infections in humans, such as urinary tract infection, implying a risk of foodborne disease. Although isolates from products labeled “organic” were less extensively antibiotic resistant than other isolates, they did not appear to be less virulent. These findings suggest that retail chicken products in the United States, even if they are labeled “organic,” pose a potential health threat to consumers because they are contaminated with extensively antibiotic-resistant and, presumably, virulent E. coli isolates.

scholarly journals NikAB- or NikB-Dependent Intracellular Recombination between Tandemly Repeated oriT Sequences of Plasmid R64 in Plasmid or Single-Stranded Phage Vectors

2003 ◽  
Vol 185 (13) ◽  
pp. 3871-3877 ◽  
Author(s):  
Nobuhisa Furuya ◽  
Teruya Komano
Keyword(s):  
Escherichia Coli ◽  
Dna Transfer ◽  
The Other ◽  
E Coli ◽  
Core Sequence ◽  
Bacterial Plasmid ◽  
Plasmid R64 ◽  
Dna Processing ◽  
Origin Of Transfer

ABSTRACT The origin of transfer (oriT) of a bacterial plasmid plays a key role in both the initiation and termination of conjugative DNA transfer. We have previously shown that a conjugation-dependent recombination between the tandem R64 oriT sequences cloned into pHSG398 occurred, resulting in the deletion of the intervening sequence during DNA transfer. In this study, we tandemly cloned two oriT sequences of IncI1 plasmid R64 into pUC18. Specific recombination between the two oriT sequences in pUC18 was observed within Escherichia coli cells harboring mini-R64. This recombination was found to be independent of both the recA gene and conjugative DNA transfer. The R64 genes nikA and nikB, required for conjugal DNA processing, were essential for this recombination. Although a fully active 92-bp oriT sequence was required at one site for the recombination, the 44-bp oriT core sequence was sufficient at the other site. Furthermore, when two oriT sequences were tandemly cloned into the single-stranded phage vector M13 and propagated within E. coli cells, recombination between the two oriT sequences was observed, depending on the nikB gene. These results suggest that the R64 relaxase protein NikB can execute cleavage and rejoining of single-stranded oriT DNA within E. coli cells, whereas such a reaction in double-stranded oriT DNA requires collaboration of the two relaxosome proteins, NikA and NikB.

Correlation of cefpodoxime susceptibility with cephalothin and cefuroxime for urinary tract isolates

2014 ◽  
Vol 63 (2) ◽  
pp. 218-221 ◽  
Author(s):  
David A. Bookstaver ◽  
Christopher M. Bland ◽  
Mitchell W. Woodberry ◽  
Karon B. Mansell
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Error Rate ◽  
Surrogate Marker ◽  
Error Rates ◽  
The Other ◽  
Colony Count ◽  
Major Error ◽  
E Coli ◽  
Microscan System

This study attempted to determine whether cefuroxime was superior to cephalothin as a surrogate marker for cefpodoxime among urinary tract isolates. The MicroScan system (Siemens) was used to determine susceptibility for cephalothin and cefuroxime on consecutive cultures with a colony count of ≥50 000 organisms. Simultaneously, an Etest (bioMérieux) for cefpodoxime was conducted. The cefpodoxime interpretation was compared to that of the other two agents, and the categorical agreement was calculated, defined as the percentage of identical susceptibility interpretations. Cefuroxime (83 %) had a significantly higher categorical agreement than cephalothin (63 %) among 300 isolates (P<0.01). The major error rate was 16 % for cephalothin and 3 % for cefuroxime. The very major error rate was 7 % for cephalothin and 14 % for cefuroxime among the 14 cefpodoxime-resistant isolates. For Escherichia coli, the major error rates were 15 % and 1 % for cephalothin and cefuroxime, respectively. Very major error rates were 9 % for both agents. Cefuroxime was a better predictor of cefpodoxime susceptibility than cephalothin, and appears to be the preferred surrogate agent for the MicroScan system, particularly for E. coli.

scholarly journals In Vitro Activity of Newer and Conventional Antimicrobial Agents, Including Fosfomycin and Colistin, against Selected Gram-Negative Bacilli in Kuwait

Pathogens ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 75 ◽  
Author(s):  
Wadha Alfouzan ◽  
Rita Dhar ◽  
David Nicolau
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Agents ◽  
The Other ◽  
In Vitro Activity ◽  
Limited Data ◽  
Gram Negative ◽  
E Coli ◽  
Microbroth Dilution

Limited data are available on susceptibilities of these organisms to some of the recently made accessible antimicrobial agents. The in vitro activities of newer antibiotics, such as, ceftolozane/tazobactam (C/T) and ceftazidime/avibactam (CZA) along with some “older” antibiotics, for example fosfomycin (FOS) and colistin (CL) were determined against selected strains (resistant to ≥ 3 antimicrobial agents) of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Minimum inhibitory concentrations (MIC) were determined by Clinical and Laboratory Standards Institute microbroth dilution. 133 isolates: 46 E. coli, 39 K. pneumoniae, and 48 P. aeruginosa were tested. Results showed that E. coli isolates with MIC50/90, 0.5/1 μ g / mL for CL; 4/32 μ g / mL for FOS; 0.25/32 μ g / mL for C/T; 0.25/8 μ g / mL for CZA, exhibited susceptibility rates of 95.7%, 97.8%, 76.1%, and 89.1%, respectively. On the other hand, K. pneumoniae strains with MIC50/90, 0.5/1 μ g / mL for CL; 256/512 μ g / mL for FOS; 2/128 μ g / mL for C/T; 0.5/128 μ g / mL for CZA showed susceptibility rates of 92.3%, 7.7%, 51.3%, and 64.1%, respectively. P. aeruginosa isolates with MIC50/90, 1/1 μ g / mL for CL; 128/128 μ g / mL for C/T; 32/64 μ g / mL for CZA presented susceptibility rates of 97.9%, 33.3%, and 39.6%, respectively. Higher MICs were demonstrated against most of the antibiotics. However, CL retained efficacy at low MICs against most of the isolates tested.

Sign in / Sign up

Export Citation Format

Share Document