A Most Probable Number Method for the Enumeration of Legionella Bacteria in Water

1991 ◽  
Vol 24 (2) ◽  
pp. 143-147 ◽  
Author(s):  
N. A. Grabow ◽  
R. Kfir ◽  
W. O. K. Grabow
Keyword(s):  
Water Samples ◽  
Membrane Filtration ◽  
Quantitative Method ◽  
Fluorescent Antibody ◽  
Most Probable Number ◽  
Probable Number ◽  
Comparative Tests ◽  
Antibody Staining ◽  
Direct Fluorescent Antibody ◽  
Yeast Extract Agar

A new quantitative method for the enumeration of Legionella bacteria in water is described. Appropriate tenfold serial dilutions of water samples concentrated by membrane filtration are plated in triplicate on buffered charcoal yeast extract agar. After incubation for 3 days representative smears from individual plates are tested for the presence of Legionella by direct fluorescent antibody staining. The number of positive plates in each dilution is used to calculate the Legionella count by means of conventional most probable number statistics. In comparative tests on a variety of water samples this method yielded significantly higher counts than previously used procedures.

Inactivation of Cryptosporidium parvum Oocysts in Cider by Flash Pasteurization

2001 ◽  
Vol 64 (4) ◽  
pp. 523-527 ◽  
Author(s):  
MING QI DENG ◽  
DEAN O. CLIVER
Keyword(s):  
Cryptosporidium Parvum ◽  
Fluorescent Antibody ◽  
Most Probable Number ◽  
Probable Number ◽  
Log Reduction ◽  
Antibody Staining ◽  
Heat Treated ◽  
Infected Cells ◽  
Medical Importance

Cryptosporidium parvum is a well-recognized pathogen of significant medical importance, and cider (apple juice) has been associated with foodborne cryptosporidiosis. This study investigated the effect of flash pasteurization on the viability of contaminant C. parvum oocysts. Cider inoculated with oocysts was heated at 70 or 71.7°C for 5, 10, or 20 s, and oocyst viability was measured by a semiquantitative in vitro infectivity assay. By infecting multiple wells of confluent Madin-Darby bovine kidney cells with serial dilutions of heat-treated oocysts and examining infected cells by indirect fluorescent antibody staining, the most probable number technique was applied to quantify log reduction of oocyst viability. Heating for 10 or 20 s at either temperature caused oocyst killing of at least 4.9 log (or 99.999%), whereas oocyst inactivation after pasteurization for 5 s at 70 and 71.7°C was 3.0 log (99.9%) and 4.8 log (99.998%), respectively. Our results suggested that current practices of flash pasteurization in the juice industry are sufficient in inactivating contaminant oocysts.

Comparative study of membrane filtration and enrichment media for the isolation and enumeration of Pseudomonas aeruginosa from sewage, surface water, and swimming pools

1985 ◽  
Vol 31 (8) ◽  
pp. 686-692 ◽  
Author(s):  
A. H. Havelaar ◽  
M. During ◽  
E. H. M. Delfgou-Van Asch
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Membrane Filtration ◽  
Culture Media ◽  
Polluted Water ◽  
Most Probable Number ◽  
Cellulose Ester ◽  
Swimming Pools ◽  
Probable Number ◽  
Membrane Filters ◽  
Swimming Water

The recovery of Pseudomonas aeruginosa on several selective culture media was tested using raw sewage and secondary sewage effluent samples as well as spiked chlorinated imitation swimming water and samples from whirlpools. mPA-medium B gave good recovery of both vital and chlorine-injured P. aeruginosa and selectivity was greater than 90% when analysing whirlpool samples. It is therefore the medium recommended for examination of chlorinated swimming pools. When analysing sewage polluted water with the mPA-B medium, reduced selectivity was noted from low verification rates and from overgrowth by competitive flora. A modified medium (mPA-D; addition of cetrimide, omission of sulphapyridine and actidione) was more selective and sufficiently recovered noninjured cells. Chlorine-injured cells were completely inhibited, however. C-390 (9-chloro-9-(4-diethylaminophenyl)-10-phenylacridan) was confirmed to be highly selective for P. aeruginosa when used in spread plates at a concentration of 30 μg/mL; P. aeruginosa was slightly inhibited. However, the medium could not be used with conventional membrane filtration techniques, because cellulose ester filters interfered with the selective action of C-390. Selectivity could be improved by using Gelman Tuffryn (polysulphone) filters and increasing the C-390 concentration to 120 μg/mL. At this concentration, however, the medium was strongly inhibitory to P. aeruginosa; resuscitation only partially improved recovery. Two other membrane filtration media were tested. Both cetrimide – nalidixic acid agar and Drake's medium No. 19 were inhibitory to chlorine-injured cells. Several types of membrane filters were tested and there was little difference between them. In the most-probable-number technique, recovery of P. aeruginosa was shown to be excellent when using asparagine broth. Malachite green broth was strongly inhibitory to chlorine-injured P. aeruginosa.

The relationship between three potential pathogens and pollution indicator organisms in Nova Scotian coastal waters

1983 ◽  
Vol 29 (10) ◽  
pp. 1261-1269 ◽  
Author(s):  
W. J. Robertson ◽  
R. S. Tobin
Keyword(s):  
Membrane Filtration ◽  
Indicator Bacteria ◽  
Fecal Coliforms ◽  
Most Probable Number ◽  
Indicator Organisms ◽  
Fecal Indicator ◽  
Filtration Method ◽  
Probable Number ◽  
Pollution Indicator ◽  
Nova Scotian

Fifteen stations, in two estuaries, along the Northumberland Strait of Nova Scotia were examined between June and September 1981 for a relationship between the concentrations of commonly monitored fecal indicator bacteria and the potential pathogens Candida albicans, Pseudomonas aeruginosa, and Vibrio parahaemolyticus. Increased densities of these three organisms were usually associated with high densities of indicator bacteria. Whereas C. albicans and P. aeruginosa occur in human fecal wastes, V. parahaemolyticus is indigenous to the marine environment and positively responds to elevated nutrient levels in sewage. There is also some evidence that these bacteria survive as long or longer in marine waters than the common indicator bacteria. While membrane-filtration techniques for the enumeration of C. albicans and P. aeruginosa proved satisfactory, a V. parahaemolyticus membrane-filtration method lacked specificity and was supplemented by a most-probable-number method. In marine recreational and shellfish waters, these three organisms could complement fecal coliforms and fecal streptococci as indicators of human fecal contamination.

scholarly journals Quality of water sources in Southwestern Uganda using the compartment bag test (CBT): a cross-sectional descriptive study

2019 ◽  
Vol 9 (4) ◽  
pp. 683-693
Author(s):  
Richard Onyuthi Apecu ◽  
Lucas Ampaire ◽  
Edgar Mugema Mulogo ◽  
Fred Norman Bagenda ◽  
Afsatou Traore ◽  
...  
Keyword(s):  
Water Samples ◽  
Water Sources ◽  
World Health ◽  
Most Probable Number ◽  
Physical Parameters ◽  
Probable Number ◽  
Gravitational Flow ◽  
Quality Of Water ◽  
Compartment Bag Test

Abstract The aim of this study was to assess the bacteriological quality of water sources in the two rural areas of Uganda using the compartment bag test (CBT). In total, 200 water samples were collected from 69 different water sources and processed within 6 h of collection. Positive and negative controls were processed each day together with water samples. Physical parameters were measured in situ. Descriptive statistics were used to generate mean, minimum, maximum, standard deviations and percentages. The results indicated that 29% of the water sources met the National Standards and World Health Organization (WHO) Guidelines for drinking water. Sixty percent of the borehole, 44% of gravitational flow taps and 14% of roof rain water met the required standards. Of the open water sources, 75% of the rivers, 50% of open channels and 43% of unprotected dug wells plus 25% of protected springs and 9% of gravitational flow schemes had most probable number counts >100 Escherichia coli/100 mL of water. Most of the water sources in the study areas were not fit for human consumption without prior treatment. The CBT was found to be robust and easy to use in all field situations. The mean physical parameters of water sources were within the acceptable limits.

scholarly journals Genus Alga pada Lahan Sawah Organik yang Ditanami Padi Lokal dan Inhibrida di Subak Jatiluwih, Tabanan

2019 ◽  
Vol 9 (2) ◽  
pp. 112
Author(s):  
SAWIDYA FITRIYANI ◽  
I WAYAN DANA ATMAJA ◽  
NI NENGAH SONIARI
Keyword(s):  
Soil Fertility ◽  
Research Method ◽  
Quantitative Method ◽  
Rice Fields ◽  
Most Probable Number ◽  
Water Sampling ◽  
Probable Number ◽  
Organic Rice ◽  
Soil And Water

Algae Genus in Organic Rice Fields Planted with Local and Inhibrida Rice in Subak Jatiluwih, Tabanan. The abundance of microalgae in rice fields, especially microalgae from Cyanophyta division that are capable of fixing nitrogen, is very important helping maintain soil fertility. The aim of this study was to find out the genus of algae in organic rice fields of Subak Jatiluwih, Tabanan. The research was conducted from September 2018 to April 2019. Sampling was done in Subak Jatiluwih. Algae breeding were carried out at Biology and Physics Laboratory, Faculty of Agriculture, Udayana University. This research method uses descriptive quantitative. The implementation of the research included the determination of location, soil and water sampling, identification of algae, and analysis of algae genera. Enrichment algae was carried out using the MPN method, results of the analysis of algae genus were found in 37 genera from 3 divisions i.e Chlorophyta, Cyanophyta and Chrysophyta. Descriptive quantitative method Most Probable Number (MPN) calculation conclude that there are not much different from the Local and Inhibrida rice fields. The maximum population algae of local rice fields is 1.100 cell g-1 and Inhibrida rice fields is >1.100 cell g-1 of land. The minimum population is 3,6 cell g-1 of land in local rice fields, and 9,2 cell g-1 of land in Inhibrida rice fields.

scholarly journals Is Drinking Water Sources Safe for Drink? A Multicenter Assessment of Fecal Contamination of Drinking Water Sources in Tigray Region, Ethiopia

2019 ◽  
Author(s):  
Goyitom Gebremedhn ◽  
Abera Aregawi Berhe ◽  
Abraham Aregay Desta ◽  
Lemlem Legesse
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Fecal Coliform ◽  
Fecal Contamination ◽  
Water Sources ◽  
Capital City ◽  
Most Probable Number ◽  
Probable Number ◽  
Tigray Region ◽  
Drinking Water Sources

Abstract Background Fecal contamination of drinking water sources is the main cause of diarrhea with estimated incidence of 4.6 billion episodes and 2.2 million deaths every year. Methods A total of 145 water samples of different source type were collected from different areas in Tigray region from August 2018 to January 2019. The water samples from each site were selected purposively which involved sampling of water sources with the highest number of users and functionality status during the study period. Most Probable Number (MPN) protocol was used for the bacteriological analysis of the samples. Results A total of 145 water samples were collected from six zones in Tigray region, Ethiopia from August 2018 to January 2019. The study indicated that 63(43.5%) of the water samples were detected to have fecal coliform which is E.coli. In Mekelle city, which is the capital city of Tigray region, three in five 34(60.7%) of the collected samples were confirmed to have fecal coliform. Water samples from health facilities were 9.48 times [AOR=9.48, 95%CI: (1.59, 56.18)] more likely to have fecal coliform. Water samples from wells were 10.23 times [AOR=10.23, 95%CI: (2.74, 38.26)] more likely to have fecal coliform than water samples from Tap/Pipe. Similarly, water samples from hand pumps were 22.28 times [AOR=22.28, 95%CI: (1.26, 393.7)] more likely to have fecal coliform than water samples from Tap/Pipe. Water samples reported to be not chlorinated were 3.51 times [AOR=3.51, 95%CI: (1.35, 9.13)] more likely to have fecal coliform than water samples from chlorinated sources. Conclusion In this study all water source, including the chlorinated drinking water sources, were found highly contaminated with fecal origin bacteria. This may be mainly due to constructional defects, poor sanitation inspection, poor maintenance, intermittent water supply and irregular chlorination.

Detection of Coliform, faecal Coliform And Total Bacterial Count From Drinking Water Of Varanasi (U.P.) India

2021 ◽  
Vol 27 (2) ◽  
Author(s):  
Alok Kumar Singh ◽  
Anand Prakash Singh ◽  
Sanjay Srivastava
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Tap Water ◽  
Bacterial Count ◽  
Most Probable Number ◽  
Total Bacterial Count ◽  
Indicator Organisms ◽  
Cross Sectional ◽  
Probable Number ◽  
Hand Pump

In India source of drinking water at Varanasi city for common people are tap water, well, hand pump, Ganga river and stored tank water collected from bore well. All water samples were studied to assess their bacteriological characteristics and suitability for potable purposes. A cross-sectional epidemiological method was adopted to investigate the drinking water of six different sites of Varanasi city. The bacteriological examination of water samples included the most probable number of presumptive coliforms, faecal coliforms, and total bacterial count. The results showed that the total coliform count was detected in all the site. In all the methods coliforms presence was indicated. Maximum number of coliform observed in all the seasons, were from river and well water followed by hand pump, tap water and stored tank. The most common group of indicator organisms used in water quality monitoring are coliforms. These organisms are representative of bacteria normally present in the intestinal tract of mammals including human. Contamination of water may occur through different way like sewage disposal in the river, seepage of bathing near sites, fecal excreta of human, bird and other animals. Improving and expanding the existing water treatment and sanitation systems are more likely to provide good, safe and sustainable sources of water in the long term.

scholarly journals Isolation and Enumeration of Escherichia coli from Soil and Water

2020 ◽  
Vol 36 (2) ◽  
pp. 75-77
Author(s):  
Anindita Bhowmik ◽  
Sunjukta Ahsan
Keyword(s):  
Escherichia Coli ◽  
Water Samples ◽  
Gas Production ◽  
Soil Samples ◽  
Most Probable Number ◽  
Biochemical Tests ◽  
Probable Number ◽  
E Coli ◽  
Dilution Series

Majority of the population of Bangladesh depend on tap or surface water as their source of water supply. This study was carried out to examine the microbial quality of both water and soil collected from different places using the multiple tube fermentation technique to determine coliform count by the most probable number (MPN) method in brilliant green lactose broth (BGLB) media.Inoculum from positive tubes of the presumptive test were further transferred on eosinemethylene blue (EMB) and MacConkey agar.The organisms isolated were further characterized using biochemical tests. Out of 93 water samples, 30 (32.26%) indicated the presence of lactose fermenter and gas producer in all 3 tubes of dilution series using inoculum quantities of 1.0, 0.1 and 0.01 ml, whereas out of 85 soil samples, 45 (52.94%) showed acid and gas production in all 3 tubes of dilution series.Among 85 soil samples, 40 samples that contained at least one positive in each dilution series and among 93 water samples, 31 samples that contained at least one positive in each dilution series were further re-identified with biochemical tests.This study showed 30.59% soil isolates and 26.88% water isolates were Escherichia coli which highlighted the fact that both water and soil act as a major reservoir of E.coli, which indicates possible fecal contamination as well as presence of potentially pathogenic E. coli. Bangladesh J Microbiol, Volume 36 Number 2 December 2019, pp 75-77

scholarly journals Investigating the presence of enteric bacteria and their antibiotic resistance in drinking water samples of slum households in Port City Chattogram, Bangladesh

2020 ◽  
Author(s):  
Sidratun Nur Chowdhury ◽  
Nazifa Rafa ◽  
Sayed Mohammad Nazim Uddin ◽  
A. K. M. Moniruzzaman Mollah
Keyword(s):  
Water Samples ◽  
Integrated Approach ◽  
Enteric Bacteria ◽  
Fecal Coliforms ◽  
Coliform Bacteria ◽  
Penicillin G ◽  
Most Probable Number ◽  
Port City ◽  
Probable Number ◽  
Unsafe Water

Abstract Globally, unsafe water supplies due to contamination with fecal coliforms are major issues in urban slums. To determine the presence of microbial risk, water samples were collected from three slums in the port city Chattogram and the most probable number (MPN) method was used to test for the presence of fecal coliform. All of the samples tested positive by the MPN test. The highest count was 1,100 MPN/100 mL and the lowest count was 7.2 MPN/100 mL. Water stored in containers was prone to being more contaminated than water collected directly from the source. To understand the antibiotic resistivity of the coliform bacteria isolated from the water samples, antibiotic susceptibility was evaluated using the Kirby-Bauer disc method for six antibiotics. All the bacteria were 100% resistant to penicillin-G and ampicillin, and 91.7% showed resistance to amoxicillin and mecillinam. An integrated approach to water, sanitation, and hygiene education must be undertaken when providing sustainable interventions in slums.

scholarly journals Detection ofCryptosporidium molnariOocysts from Fish by Fluorescent-Antibody Staining Assays forCryptosporidiumspp. Affecting Humans

2011 ◽  
Vol 77 (5) ◽  
pp. 1878-1880 ◽  
Author(s):  
Rona Barugahare ◽  
Michelle M. Dennis ◽  
Joy A. Becker ◽  
Jan Šlapeta
Keyword(s):  
Ribosomal Dna ◽  
Fluorescent Antibody ◽  
Small Subunit ◽  
Rapid Diagnosis ◽  
Antibody Staining ◽  
Direct Fluorescent Antibody ◽  
Murray Cod ◽  
Diagnosis Of Infection ◽  
Formalin Fixed ◽  
Fluorescent Antibody Staining

ABSTRACTThree direct fluorescent-antibody staining assay kits for the detection of zoonoticCryptosporidiumspecies were used to detectCryptosporidium molnarifrom Murray cod, and the cryptosporidia were characterized by using small-subunit (SSU) ribosomal DNA (rDNA). To facilitate rapid diagnosis of infection, this study demonstrated that all three kits detected freshC. molnariand two kits detected formalin-fixed oocysts.

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