Substrate Supporting Disc Method for Confirmed Detection of Total Coliforms and E. coli in all Foods: Collaborative Study

1993 ◽  
Vol 76 (5) ◽  
pp. 988-1005 ◽  
Author(s):  
Philip T Feldsine ◽  
Maria T Falbo-Nelson ◽  
David L Hustead ◽  
◽  
J Aaronson ◽  
...  
Keyword(s):  
Collaborative Study ◽  
Total Coliform ◽  
Food Type ◽  
Coliform Bacteria ◽  
Pork Sausage ◽  
E Coli ◽  
Fresh Frozen ◽  
Uninoculated Control ◽  
Liquid Milk ◽  
Control Samples

Abstract The Coli Complete® substrate supporting disc (SSD) method for simultaneous confirmed total coliform count and Escherichia coli determination in all foods was compared with AOAC most probable number (MPN) methods, 966.23 and 966.24. Twenty-nine laboratories participated in this collaborative study in which 6 food types were analyzed. Four food types, raw ground beef, pork sausage, raw liquid milk, and nut meats, were naturally contaminated with coliform bacteria. Two foods, dry egg and fresh frozen vegetables, were seeded with coliforms. Three food types, ground beef, raw liquid milk, and pork sausage, were naturally contaminated with E. coli. Although pork sausage was naturally contaminated, the level was very low (<10/50 g); therefore, additional E. coli were inoculated into 1 lot of this food type. Three food types, nut meats, dry egg, and fresh frozen vegetables, were inoculated with E. coli. For naturally contaminated samples, duplicate determinations were made on 3 separate lots for each food type. For inoculated samples, low, medium, and high contamination levels plus uninoculated control samples were examined in duplicate. Data were analyzed separately for total coliform bacteria and for E. coli. Mean log MPN counts were determined by the SSD method and the appropriate AOAC MPN method. Results were then analyzed for repeatability, reproducibility, and mean log MPN statistical equivalence. Results were statistically equivalent for all total coliform levels in all food types except frozen vegetable and raw nut meat uninoculated control samples and 1 lot of pork sausage where the SSD method produced statistically significant greater numbers. For the E. coli determinations, results were statistically equivalent across all samples and all levels for each food type. The SSD method has been adopted first action by AOAC International for confirmed detection of total coliforms and E. coli in all foods.

scholarly journals Bacterial Contamination of Drinking Water in Guadalajara, Mexico

2018 ◽  
Author(s):  
Francesca Rubino ◽  
Yahaira Corona ◽  
José Guadalupe Jiménez Pérez ◽  
Charlotte D. Smith
Keyword(s):  
Drinking Water ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
E Coli ◽  
Chlorine Residual ◽  
Piped Water ◽  
Regulatory Limits ◽  
Access To Water

In many regions where drinking water supply is intermittent and unreliable, households adapt by storing water in cisterns or rooftop tanks. Both intermittent supply and stored water can be vulnerable to contamination by microorganisms with deleterious health effects. The Guadalajara Metropolitan Area is a rapidly growing urban center with over five million residents where household storage is nearly ubiquitous. This pilot study was conducted in July 2018 to examine the microbiological quality of drinking water in Guadalajara. Samples were tested for free available chlorine residual, total coliform bacteria, and E. coli. A survey on access to water and public perspectives was also conducted. Water exiting rooftop tanks exceeded regulatory limits for total coliform levels in half of the homes studied. Piped water arriving at two homes had total coliform levels that far exceeded regulatory limits. No E. coli were detected in any of the samples. Only 35% of homes had a chlorine residual between the recommended 0.2 and 1.5 mg/L. Many homes reported unpleasant odors and colors. Only 7% of residents drank the piped water. Future studies are needed, especially during April and May when many homes reported a higher disruption to water service.

Fluorogenic Assay for Rapid Detection of Escherichia coli in Chilled and Frozen Foods: Collaborative Study

1988 ◽  
Vol 71 (3) ◽  
pp. 589-602
Author(s):  
Lloyd J Moberg ◽  
Mary K Wagner ◽  
Lisa A Kellen
Keyword(s):  
Escherichia Coli ◽  
Uv Light ◽  
Collaborative Study ◽  
Food Samples ◽  
Official Method ◽  
Frozen Foods ◽  
Pork Sausage ◽  
E Coli ◽  
Aoac Method ◽  
Better Than

Abstract A collaborative study was conducted to compare a proposed LSTMUG method with the AOAC official method for Escherichia coli detection. E. coli produces an enzyme, β-glucuronidase, which cleaves the substrate, 4-methyl-umbelliferyl-β-D-glucuronide (MUG), to yield a fluorescent end product. Incorporation of the MUG substrate into lauryl tryptose broth (LST) enables a rapid quantitative method for screening E. coli, which is detected by fluorescence of the medium under longwave UV light. In this collaborative study, 5 food samples, 2 frozen (entree sauce/gravy and dairy topping) and 3 chilled (hamburger, pork sausage, and cheese), were tested for E. coli detection by 17 collaborating laboratories. Results indicate that the LST-MUG method is equal to or better than the current AOAC method for detecting E. coli. The LST-MUG method has been adopted official first action

scholarly journals Bacterial Contamination of Drinking Water in Guadalajara, Mexico

2018 ◽  
Vol 16 (1) ◽  
pp. 67 ◽  
Author(s):  
Francesca Rubino ◽  
Yahaira Corona ◽  
José Guadalupe Jiménez Pérez ◽  
Charlotte Smith
Keyword(s):  
Drinking Water ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
E Coli ◽  
Chlorine Residual ◽  
Piped Water ◽  
Regulatory Limits ◽  
Access To Water

In many regions where drinking water supply is intermittent and unreliable, households adapt by storing water in cisterns or rooftop tanks. Both intermittent supply and stored water can be vulnerable to contamination by microorganisms with deleterious health effects. The Metropolitan Zone of Guadalajara is a rapidly growing urban center with over five million residents where household storage is nearly ubiquitous. This pilot study was conducted in July 2018 to examine the microbiological quality of drinking water in Guadalajara. Samples were tested for free available chlorine residual, total coliform bacteria, and Escherichia coli. A survey on access to water and public perspectives was also conducted. Water exiting rooftop tanks exceeded regulatory limits for total coliform levels in half of the homes studied. Piped water arriving at two homes had total coliform levels that far exceeded regulatory limits. No E. coli were detected in any of the samples. Only 35% of homes had a chlorine residual between the recommended 0.2 and 1.5 mg/L. Many homes reported unpleasant odors and colors. Only 7% of residents drank the piped water. Future studies are needed, especially during April and May when many homes reported a higher disruption to water service.

CONSUMPTION OF RAW WATER – THE HEALTH RISKS RELATED TO THE PRESENCE OF HEAVY METALS AND „ESCHERICHIA COLI“

2021 ◽  
Author(s):  
Mirjana Grujović ◽  
◽  
Katarina Mladenović ◽  
Zoran Simić ◽  
Simona Đuretanović
Keyword(s):  
Escherichia Coli ◽  
Trace Elements ◽  
Health Risks ◽  
Water Samples ◽  
Major And Trace Elements ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
Mountain Stream ◽  
E Coli ◽  
Colorimetric Test

This research aimed to investigate the quality of drinking water from the rural area of village Pajsijević (Šumadija, central Serbia). The water is consumed as raw since it is not purified or chlorinated before consumption. The water was collected at three sampling points – in the spring of Kotlenik Mountain stream (W1 sample), in the local reservoir (W2 sample), and from the tap (W3 sample). Also, the sediment samples (soil and sand) were analyzed, too. The health risks related to the presence and concentration of some major and trace elements (Ca, Cr, Cu, Fe, Mg, Mn, Ni, Zn) and N, NO, NN3, NH4, P, P2O5, and PO4 were evaluated. Additionally, the presence and the number of total coliform bacteria and Escherichia coli (as an indicator of fecal contamination) were evaluated. The concentrations of analyzed major and trace elements in all water samples were below those at which toxic effects may occur. The exception was the concentrations of Fe (2.02 – 2012 mg/L), which were higher than is allowed. The origin of Fe in water is from sediment (soil and sand), which also showed high content of Fe (3006.0 mg/g and 2229.9 mg/g, respectively). The results of the Colorimetric test indicated the presence of coliform bacteria as well as the presence of E. coli in all water samples. Further research needs to include characterization of isolated coliform bacteria and serological investigation of E. coli strains in order to evaluate the risks of consumption related to waterborne illness.

Comparison of the role of attachment, aggregation and internalisation of microorganisms in UVC and UVA (solar) disinfection

2011 ◽  
Vol 63 (9) ◽  
pp. 1823-1831 ◽  
Author(s):  
Françoise Bichai ◽  
Simon Léveillé ◽  
Benoit Barbeau
Keyword(s):  
Membrane Filtration ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
Bacterial Inactivation ◽  
Protective Mechanisms ◽  
Solar Disinfection ◽  
E Coli ◽  
C Elegans ◽  
Natural Aggregates ◽  
The Impact

In this comparative study, the impact of two microbial protective mechanisms against simulated UVA disinfection was assessed by using protocols previously developed for UVC disinfection assays. (i) The impact of natural microorganism aggregation and attachment to particles was assessed by targeting total coliform bacteria in natural surface water samples. (ii) The impact of bacteria internalisation by zooplankton was assessed by using C. elegans nematodes as a model host and E. coli as a bacterial target for UVA inactivation. Dispersion of natural aggregates by blending prior to UVA exposure was shown to enhance the inactivation rate of total coliforms as compared to untreated raw water. Removal of particles by an 8-μm membrane filtration did not improve UVA disinfection efficiency. Twenty-four per cent of the highest applied UVA fluence was found to reach internalised E. coli in nematodes. Both aggregation and internalisation showed similar impact as protective mechanisms against UVA and UVC bacterial inactivation.

ColiComplete® Substrate-Supporting Disc Method for Confirmed Detection of Total Coliforms and Escherichia coli in All Foods: Comparative Study

1994 ◽  
Vol 77 (1) ◽  
pp. 58-63 ◽  
Author(s):  
Philip T Feldsine ◽  
Maria T Falbo-Nelson ◽  
David L Hustead
Keyword(s):  
Escherichia Coli ◽  
Comparative Study ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Probable Number ◽  
Total Coliforms ◽  
E Coli ◽  
Total Coliform Bacteria ◽  
Better Than

Abstract The ColiComplete® substrate-supporting disc (SSD) method for simultaneous confirmed total coliform count and Escherichia coli determination in all foods was compared with the AOAC most probable number (MPN) methods 966.23 and 966.24. In this comparative study, 20 water and food types were analyzed; 7 of these foods were naturally contaminated with coliform bacteria, 6 food types were naturally contaminated with E. coli, and the remaining foods were inoculated with coliform bacteria and/or E. coli. Data were analyzed separately for total coliform bacteria and for E. coli. Mean log MPN counts were determined by the SSD method and the appropriate AOAC MPN procedure. Results were then analyzed for mean log MPN differences and variance, according to methods described by AOAC INTERNATIONAL Results for both total conforms and E. coli indicate that the SSD method is equivalent to or better than AOAC MPN methods 966.23 and 966.24.

scholarly journals Is it Possible to Sanitize Athletes' Shoes?

2015 ◽  
Vol 50 (2) ◽  
pp. 126-132 ◽  
Author(s):  
Gabriele Messina ◽  
Sandra Burgassi ◽  
Carmela Russo ◽  
Emma Ceriale ◽  
Cecilia Quercioli ◽  
...  
Keyword(s):  
Fungal Infections ◽  
Bacterial Count ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
Total Bacterial Count ◽  
E Coli ◽  
Enterococcus Spp ◽  
Before And After ◽  
Unpleasant Odor ◽  
Staphylococcus Spp

Context: Footwear should be designed to avoid trauma and injury to the skin of the feet that can favor bacterial and fungal infections. Procedures and substances for sanitizing the interior of shoes are uncommon but are important aspects of primary prevention against foot infections and unpleasant odor. Objective: To evaluate the efficacy of a sanitizing technique for reducing bacterial and fungal contamination of footwear. Design: Crossover study. Setting: Mens Sana basketball team. Patients or Other Participants: Twenty-seven male athletes and 4 coaches (62 shoes). Intervention(s): The experimental protocol required a first sample (swab), 1/shoe, at time 0 from inside the shoes of all athletes before the sanitizing technique began and a second sample at time 1, after about 4 weeks, April 2012 to May 2012, of daily use of the sanitizing technique. Main Outcome Measure(s): The differences before and after use of the sanitizing technique for total bacterial count at 36°C and 22°C for Staphylococcus spp, yeasts, molds, Enterococcus spp, Pseudomonas spp, Escherichia coli, and total coliform bacteria were evaluated. Results: Before use of the sanitizing technique, the total bacterial counts at 36°C and 22°C and for Staphylococcus spp were greater by a factor of 5.8 (95% confidence interval [CI] = 3.42, 9.84), 5.84 (95% CI = 3.45, 9.78), and 4.78 (95% CI = 2.84, 8.03), respectively. All the other comparisons showed a reduction in microbial loads, whereas E coli and coliforms were no longer detected. No statistically significant decrease in yeasts (P = .0841) or molds (P = .6913) was recorded probably because of low contamination. Conclusions: The sanitizing technique significantly reduced the bacterial presence in athletes' shoes.

Yeasts and coliform bacteria of water accumulated in bromeliads of mangrove and sand dune ecosystems of southeast Brazil

1993 ◽  
Vol 39 (10) ◽  
pp. 973-977 ◽  
Author(s):  
Allen N. Hagler ◽  
Carlos A. Rosa ◽  
Paula B. Morais ◽  
Leda C. Mendonça-Hagler ◽  
Georgia M. O. Franco ◽  
...  
Keyword(s):  
Fecal Coliform ◽  
Sand Dune ◽  
Mangrove Ecosystem ◽  
Total Coliform ◽  
Fecal Coliforms ◽  
Coliform Bacteria ◽  
E Coli ◽  
Yeast Community ◽  
The Mean ◽  
Ascomycetous Yeasts

Yeasts and coliform bacteria were isolated from water that accumulated in the central cups and adjacent leaf axilae of two bromeliads, Neoregelia cruenta of a coastal sand dune and Quesnelia quesneliana of a mangrove ecosystem near the city of Rio de Janeiro, Brazil. The mean total coliform counts were above 10 000 per 100 mL for waters of both plants, but the mean fecal coliform counts were only 74 per 100 mL for Q. quesneliana and mostly undetected in water from N. cruenta. Of 90 fecal coliform isolates, 51 were typical of Escherichia coli in colony morphology and indol, methyl red, Volges–Proskauer, and citrate (IMViC) tests. Seven representatives of the typical E. coli cultures were identified as this species, but the identifications of nine other coliform bacteria were mostly dubious. The yeast community of N. cruenta was typical of plant surfaces with basidiomycetous yeasts anamorphs, and the black yeast Aureobasidium pullulans was prevalent. Quesnelia quesneliana had a substantial proportion of ascomycetous yeasts and their anamorphs, including a probable new biotype of Saccharomyces unisporus. Our results suggested that the microbial communities in bromeliad waters are typically autochtonous and not contaminants.Key words: yeasts, fecal coliforms, bromeliad waters, mangrove, Restinga.

scholarly journals Bacterial Contamination of Drinking Water in Guadalajara, Mexico

2018 ◽  
Author(s):  
Francesca Rubino ◽  
Yahaira Corona ◽  
José Guadalupe Jiménez Pérez ◽  
Charlotte Smith
Keyword(s):  
Drinking Water ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
E Coli ◽  
Chlorine Residual ◽  
Piped Water ◽  
Regulatory Limits ◽  
Access To Water

In many regions where drinking water supply is intermittent and unreliable, households adapt by storing water in cisterns or rooftop tanks. Both intermittent supply and stored water can be vulnerable to contamination by microorganisms with deleterious health effects. The Guadalajara Metropolitan Area is a rapidly growing urban center with over five million residents where household storage is nearly ubiquitous. This pilot study was conducted in July 2018 to examine the microbiological quality of drinking water in Guadalajara. Samples were tested for free available chlorine residual, total coliform bacteria, and E. coli. A survey on access to water and public perspectives was also conducted. Water exiting rooftop tanks exceeded regulatory limits for total coliform levels in half of the homes studied. Piped water arriving at two homes had total coliform levels that far exceeded regulatory limits. No E. coli were detected in any of the samples. Only 35% of homes had a chlorine residual between the recommended 0.2 and 1.5 mg/L. Many homes reported unpleasant odors and colors. Only 7% of residents drank the piped water. Future studies are needed, especially during April and May when many homes reported a higher disruption to water service.

scholarly journals A study in the experimental conditions of pesticide action on microorganisms characterizing sanitary-epidemiological safety of reservoirs

2019 ◽  
Vol 95 (8) ◽  
pp. 785-789 ◽  
Author(s):  
V. V. Aleshnya ◽  
Peter V. Zhuravlev ◽  
O. P. Panasovets
Keyword(s):  
River Water ◽  
Strain Differences ◽  
Water Source ◽  
Total Coliform ◽  
The Body ◽  
Coliform Bacteria ◽  
Experimental Conditions ◽  
E Coli ◽  
Pesticide Pollution ◽  
Total Coliform Bacteria

The paper presents experimental data on the pesticides action (molinate (OrdramA), Dinitroortocresolum and chlorophos) at concentrations of 0.01 mg /l to 10 mg/l on sanitary-indicative (TBC, total coliform bacteria, E. coli, E. faecalis), potentially pathogenic ( Ps. aeruginosa) and pathogenic (S. Derby) microflora of the river water. As the test cultures there were used isolated from the reservoir and museum strains of microorganisms. Due to the fact that the rate of decomposition ofpesticides in water increases in direct proportion to the extent of its biological contamination, the experiments were performed with the river water: native and sterilized by autoclaving. There were identified species and strain differences in the microbial response to the action of pesticides. The selectivity of OrdramA action at a concentration of 0.1 to 10 mg/l on Salmonella and of chlorophos at a concentration of 10 mg/l for Salmonella and E. coli is manifested in the stimulation of the reproduction of these bacteria. Dinitroortocresolum in concentrations of 10 mg/l and 1 mg/l gives rise in the reproduction of Pseudomonas aeruginosa and inhibits the growth of total coliform bacteria and E. coli, in a concentration of 0.1 mg/l the preparation stimulates the viability of all the studied microorganisms. When entering the body of water, pesticides were found to cause changes of biocenosis in the river water and disturb bacterial self-cleaning processes. In conditions of pesticide pollution total coliform bacteria, E. coli and E. faecalis unable to maintain their indicative value and therefore the use of only them for the evaluation of the sanitary-epidemiological status of the water source appears to be insufficient. Due to the fact that the epidemic potential of water is directly dependent on quantitative content ofpathogenic and opportunistic pathogenic microorganisms in it, the reproduction Salmonella and Pseudomonas bacteria is a negative moment from the sanitary and epidemiological point of view.

Sign in / Sign up

Export Citation Format

Share Document