Evaluation of New Components in Modified Scholten’s Medium for the Detection of Somatic Coliphages

2020 ◽  
Vol 12 (2) ◽  
pp. 148-157 ◽  
Author(s):  
Daniel Toribio-Avedillo ◽  
Javier Méndez ◽  
Maite Muniesa ◽  
Anicet R. Blanch
Keyword(s):  
Somatic Coliphages

Evaluation of bacteriophages during the treatment of sludge

2002 ◽  
Vol 46 (10) ◽  
pp. 189-194 ◽  
Author(s):  
B. Mignotte-Cadiergues ◽  
C. Gantzer ◽  
L. Schwartzbrod
Keyword(s):  
Bacteroides Fragilis ◽  
Temperature Dependent ◽  
Treatment Methods ◽  
Somatic Coliphages ◽  
Viral Contamination ◽  
Log Reduction ◽  
Ph Dependent ◽  
Somatic Coliphage ◽  
Phage Inactivation

The aim of this work was to determine the effect of liming and composting on the fate of three bacteriophages (somatic coliphages, F-RNA phages, Bacteroides fragilis phages) considered as potential indicators of viral contamination. It was shown that the three bacteriophages studied exhibited variable densities in sludge. Somatic coliphages were most abundant (104 to 105 .10 g−1 DM) then F-RNA bacteriophages (102 to 104.10 g−1 DM) and Bacteroides fragilis phages (101 to 102.10 g−1 DM). The efficacy of liming was found to be pH dependent but also sludge dependent. The pH allowing 99% elimination of somatic coliphage is close to 9 for solid sludges and close to 13.5 for liquid sludges. For composting, our findings clearly demonstrated that phage inactivation is very clearly temperature-dependent. For temperatures reaching 70°, there is a 5 log reduction in somatic coliphages while for temperature in the 50-55°C range, the drop off is only 2 log. Considering the efficacy of the treatment methods, it is clear that the well-established industrial procedures that reach temperatures in the 60-70°C range totally inactivate all 3 phages tested and present in sludge before composting.

Fate ofCryptosporidiumoocysts,Giardiacysts, and microbial indicators during wastewater treatment and anaerobic sludge digestion

1999 ◽  
Vol 45 (3) ◽  
pp. 257-262 ◽  
Author(s):  
Christian Chauret ◽  
Susan Springthorpe ◽  
Syed Sattar
Keyword(s):  
Wastewater Treatment ◽  
Clostridium Perfringens ◽  
Heterotrophic Bacteria ◽  
The Other ◽  
Anaerobic Sludge ◽  
Somatic Coliphages ◽  
Aerobic Wastewater Treatment ◽  
Sludge Digestion ◽  
Cryptosporidium Oocysts ◽  
Anaerobic Sludge Digestion

The extent of reduction in selected microorganisms was tested during both aerobic wastewater treatment and anaerobic digestion of sludge at the wastewater treatment plant in Ottawa to compare the removal of two encysted pathogenic protozoa with that of microbial indicators. Samples collected included the raw wastewater, the primary effluent, the treated wastewater, the mixed sludge, the decanted liquor, and the cake. All of the raw sewage samples were positive for Cryptosporidium oocysts and Giardia cysts, as well as for the other microorganisms tested. During aerobic wastewater treatment (excluding the anaerobic sludge digestion), Cryptosporidium and Giardia were reduced by 2.96 log10and 1.40 log10, respectively. Clostridium perfringens spores, Clostridium perfringens total counts, somatic coliphages, and heterotrophic bacteria were reduced by approximately 0.89 log10, 0.96 log10, 1.58 log10, and 2.02 log10, respectively. All of the other microorganisms were reduced by at least 3.53 log10. Sludge samples from the plant were found to contain variable densities of microorganisms. Variability in microbial concentrations was sometimes great between samples, stressing the importance of collecting a large number of samples over a long period of time. In all cases, the bacterial concentrations in the cake (dewatered biosolids) samples were high even if reductions in numbers were observed with some bacteria. During anaerobic sludge digestion, no statistically significant reduction was observed for Clostridium perfringens, Enterococcus sp., Cryptosporidium oocysts, and Giardia cysts. A 1-2 log10reduction was observed with fecal coliforms and heterotrophic bacteria. However, the method utilized to detect the protozoan parasites does not differentiate between viable and nonviable organisms. On the other hand, total coliforms and somatic coliphages were reduced by 0.35 log10and 0.09 log10, respectively. These results demonstrate the relative persistence of the protozoa in sewage sludge during wastewater treatment.Key words: Cryptosporidium, Giardia, indicators, wastewater, sludge.

scholarly journals Sunlight Inactivation of Fecal Indicator Bacteria and Bacteriophages from Waste Stabilization Pond Effluent in Fresh and Saline Waters

2002 ◽  
Vol 68 (3) ◽  
pp. 1122-1131 ◽  
Author(s):  
Lester W. Sinton ◽  
Carollyn H. Hall ◽  
Philippa A. Lynch ◽  
Robert J. Davies-Colley
Keyword(s):  
River Water ◽  
Fecal Coliform ◽  
Natural Waters ◽  
Fecal Coliforms ◽  
Somatic Coliphages ◽  
Stabilization Pond ◽  
Waste Stabilization Pond ◽  
Waste Stabilization ◽  
Photooxidative Damage ◽  
Wide Range

ABSTRACT Sunlight inactivation in fresh (river) water of fecal coliforms, enterococci, Escherichia coli, somatic coliphages, and F-RNA phages from waste stabilization pond (WSP) effluent was compared. Ten experiments were conducted outdoors in 300-liter chambers, held at 14°C (mean river water temperature). Sunlight inactivation (k S) rates, as a function of cumulative global solar radiation (insolation), were all more than 10 times higher than the corresponding dark inactivation (k D) rates in enclosed (control) chambers. The overall k S ranking (from greatest to least inactivation) was as follows: enterococci > fecal coliforms ≥ E. coli > somatic coliphages > F-RNA phages. In winter, fecal coliform and enterococci inactivation rates were similar but, in summer, enterococci were inactivated far more rapidly. In four experiments that included freshwater-raw sewage mixtures, enterococci survived longer than fecal coliforms (a pattern opposite to that observed with the WSP effluent), but there was little difference in phage inactivation between effluents. In two experiments which included simulated estuarine water and seawater, sunlight inactivation of all of the indicators increased with increasing salinity. Inactivation rates in freshwater, as seen under different optical filters, decreased with the increase in the spectral cutoff (50% light transmission) wavelength. The enterococci and F-RNA phages were inactivated by a wide range of wavelengths, suggesting photooxidative damage. Inactivation of fecal coliforms and somatic coliphages was mainly by shorter (UV-B) wavelengths, a result consistent with photobiological damage. Fecal coliform repair mechanisms appear to be activated in WSPs, and the surviving cells exhibit greater sunlight resistance in natural waters than those from raw sewage. In contrast, enterococci appear to suffer photooxidative damage in WSPs, rendering them susceptible to further photooxidative damage after discharge. This suggests that they are unsuitable as indicators of WSP effluent discharges to natural waters. Although somatic coliphages are more sunlight resistant than the other indicators in seawater, F-RNA phages are the most resistant in freshwater, where they may thus better represent enteric virus survival.

scholarly journals Enteric viruses, somatic coliphages and Vibrio species in marine bathing and non-bathing waters in Italy

2019 ◽  
Vol 149 ◽  
pp. 110570 ◽  
Author(s):  
L. Bonadonna ◽  
R. Briancesco ◽  
E. Suffredini ◽  
A. Coccia ◽  
S. Della Libera ◽  
...  
Keyword(s):  
Enteric Viruses ◽  
Vibrio Species ◽  
Somatic Coliphages ◽  
Bathing Waters

Enteric Bacteriophages as Potential Fecal Indicators in Ground Beef and Poultry Meat

2002 ◽  
Vol 65 (1) ◽  
pp. 93-99 ◽  
Author(s):  
F.-C. HSU ◽  
Y.-S. CAROL SHIEH ◽  
M. D. SOBSEY
Keyword(s):  
Microbiological Quality ◽  
Ground Beef ◽  
Chicken Meat ◽  
Detection Sensitivity ◽  
Fecal Coliforms ◽  
Poultry Meat ◽  
Chicken Breast ◽  
Fecal Indicators ◽  
Somatic Coliphages ◽  
Critical Control Points

Recovery efficiencies of enteric bacteriophages (F+ RNA coliphages, somatic coliphages, and Salmonella phages) as alternative fecal indicators were determined from ground beef and chicken breast meat using amino acid eluants (glycine and threonine) and a complex eluant (3% beef extract). Levels of F+ RNA coliphages (MS2, GA, Qβ, FI, and SP), the somatic coliphage ΦX174, and three environmental isolates of Salmonella phages (isolated from raw sewage) were assayed using three respective hosts: Escherichia coli Famp, E. coli C, and Salmonella Typhimurium. When 8% polyethylene glycol and 0.1 M NaCl were used to precipitate bacteriophages eluted with five different eluants, the highest recoveries of the three phage groups were with 0.5 M threonine and 0.25 M glycine-threonine. The average recoveries of F+ RNA coliphages, somatic coliphages, and the Salmonella phages from ground beef and chicken meat were 100, 69, and 65%, respectively, with threonine (0.5 M, pH 9.0) as the eluate. Of eight market food samples tested, F+ RNA coliphages were detected in five (63%) and somatic coliphages were detected in seven (88%). The overall detection sensitivity of the method was 3 PFU/100 g of ground beef or chicken meat. Levels of bacteriophages and bacterial indicators on chicken carcass surfaces were determined at identified critical control points at a poultry plant. Through the processing steps of evisceration, washing, and chilling, the levels of F+ RNA coliphages and fecal coliforms were reduced by 1.6 and 1.9 log10 PFU or CFU/100 g, respectively. F+ RNA coliphages and perhaps other enteric bacteriophages may be effective candidate indicators for monitoring the microbiological quality of meat, poultry, and perhaps other foods during processing. The bacteriophage concentration method developed provides a simple, rapid, and practical tool for the evaluation of fecal contamination levels in ground beef and processed chicken meat.

Virus elimination in activated sludge systems: from batch tests to mathematical modeling

2014 ◽  
Vol 70 (6) ◽  
pp. 1115-1121 ◽  
Author(s):  
Emma Haun ◽  
Katharina Ulbricht ◽  
Regina Nogueira ◽  
Karl-Heinz Rosenwinkel
Keyword(s):  
Activated Sludge ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Virus Concentration ◽  
Extended Model ◽  
Municipal Wastewater Treatment ◽  
Virus Elimination ◽  
Somatic Coliphages ◽  
Batch Tests ◽  
Activated Sludge Systems

A virus tool based on Activated Sludge Model No. 3 for modeling virus elimination in activated sludge systems was developed and calibrated with the results from laboratory-scale batch tests and from measurements in a municipal wastewater treatment plant (WWTP). The somatic coliphages were used as an indicator for human pathogenic enteric viruses. The extended model was used to simulate the virus concentration in batch tests and in a municipal full-scale WWTP under steady-state and dynamic conditions. The experimental and modeling results suggest that both adsorption and inactivation processes, modeled as reversible first-order reactions, contribute to virus elimination in activated sludge systems. The model should be a useful tool to estimate the number of viruses entering water bodies from the discharge of treated effluents.

scholarly journals Bluephage, a method for efficient detection of somatic coliphages in one hundred milliliter water samples

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Javier Méndez ◽  
Daniel Toribio-Avedillo ◽  
Raquel Mangas-Casas ◽  
Judit Martínez-González
Keyword(s):  
Water Samples ◽  
Somatic Coliphages ◽  
Efficient Detection

Optimisation of the ISO-method on enumeration of somatic coliphages (draft ISO 10705-2)

2001 ◽  
Vol 43 (12) ◽  
pp. 205-208 ◽  
Author(s):  
K. A. Mooijman ◽  
M. Bahar ◽  
N. Contreras ◽  
A. H. Havelaar
Keyword(s):  
Membrane Filtration ◽  
Viable Count ◽  
Somatic Coliphages ◽  
Layer Method ◽  
Bathing Waters ◽  
Agar Layer ◽  
Eu Project ◽  
Single Agar ◽  
Filtration Technique ◽  
The Eu

As part of the EU project “Bacteriophages in Bathing Waters” (January 1996 - June 1999) research was carried out to optimise the method for detection and enumeration of somatic coliphages in water as described in ISO/CD 10705-2 of August 1995. It was concluded that this draft ISO standard needed to be amended in certain aspects. For determining the viable count of the host culture WG5 Escherichia coli, a membrane filtration technique should be used instead of spread plate technique as the latter gives lower and less reproducible results. A freshly prepared inoculum culture of host strain WG5 should be used instead of a frozen inoculum culture as freezing of the inoculum culture is found to negatively influence the phage counts. The double agar layer method (DAL) is preferred to the single agar layer method (SAL) for performing the phage analysis as the DAL method gives higher phage counts than the SAL method.

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