scholarly journals Universal Enzyme-Based Field Workflow for Rapid and Sensitive Quantification of Water Pathogens

2021 ◽  
Vol 9 (11) ◽  
pp. 2367
Author(s):  
Angela Sun ◽  
Jo-Ann L. Stanton ◽  
Peter L. Bergquist ◽  
Anwar Sunna
Keyword(s):  
Water Samples ◽  
Sampling Method ◽  
Tap Water ◽  
Low Cost ◽  
Scale Up ◽  
Single Step ◽  
E Coli ◽  
Conventional Culture ◽  
Insoluble Particles ◽  
Acid Wash

A universal filtration and enzyme-based workflow has been established to allow for the rapid and sensitive quantification of leading pathogens Cryptosporidium parvum, Giardia gamblia, Campylobacter jejuni, and Escherichia coli from tap water samples with volumes up to 100 mL, and the potential to scale up to larger volumes. qPCR limits of quantification as low as four oocysts for Cryptosporidium, twelve cysts for Giardia, two cells for C. jejuni, and nineteen cells for E. coli per reaction were achieved. A polycarbonate filter-based sampling method coupled with the prepGEM enzyme-based DNA extraction system created a single-step transfer workflow that required as little as 20 min of incubation time and a 100 µL reaction mix. The quantification via qPCR was performed directly on the prepGEM extract, bypassing time-consuming, labour-intensive conventional culture-based methods. The tap water samples were shown to contain insoluble particles that inhibited detection by reducing the quantification efficiency of a representative pathogen (C. jejuni) to 30–60%. This sample inhibition was effectively removed by an on-filter treatment of 20% (v/v) phosphoric acid wash. Overall, the established workflow was able to achieve quantification efficiencies of 92% and higher for all four leading water pathogens, forming the basis of a rapid, portable, and low-cost solution to water monitoring.

scholarly journals Microbiologic effectiveness of boiling and safe water storage in South Sulawesi, Indonesia

2011 ◽  
Vol 9 (3) ◽  
pp. 577-585 ◽  
Author(s):  
Samir V. Sodha ◽  
M. Menon ◽  
K. Trivedi ◽  
A. Ati ◽  
M. E. Figueroa ◽  
...  
Keyword(s):  
Water Quality ◽  
Water Samples ◽  
Scale Up ◽  
Treatment Practices ◽  
Rural Districts ◽  
E Coli ◽  
South Sulawesi ◽  
The Government ◽  
The Impact ◽  
Prevalence Ratios

In Indonesia, where diarrhea remains a major cause of mortality among children <5 years, the government promotes boiling of drinking water. We assessed the impact of boiling on water quality in South Sulawesi. We surveyed randomly selected households with at least one child <5 years old in two rural districts and tested source and stored water samples for Escherichia coli contamination. Among 242 households, 96% of source and 51% of stored water samples yielded E. coli. Unboiled water samples, obtained from 15% of households, were more likely to yield E. coli than boiled samples [prevalence ratios (PR) = 2.0, 95% confidence interval (CI) 1.7–2.5]. Water stored in wide-mouthed (PR = 1.4, 95% CI = 1.1–1.8) or uncovered (PR = 1.8, 95% CI = 1.3–2.4) containers, or observed to be touched by the respondent's hands (PR = 1.6, 95% CI = 1.3–2.1) was more likely to yield E. coli. A multivariable model showed that households that did not boil water were more likely to have contaminated stored water than households that did boil water (PR = 1.9, 95% CI = 1.5–2.3). Although this study demonstrated the effectiveness of boiling in reducing contamination, overall impact on water quality was suboptimal. Future studies are needed to identify factors behind the success of boiling water in Indonesia to inform efforts to scale up other effective water treatment practices.

scholarly journals Lead Ions Removal from Natural Water Samples by Nano-Mint Waste as Benign Low Cost Biosorbent

2018 ◽  
Vol 3 (2) ◽  
pp. 116-126
Author(s):  
Tamer H. A. Hasanin ◽  
Salwa A. Ahmed ◽  
Taghreed B. Ebrahim
Keyword(s):  
Natural Water ◽  
Water Samples ◽  
Metal Ion ◽  
Sea Water ◽  
Tap Water ◽  
Low Cost ◽  
Lead Removal ◽  
Lead Uptake ◽  
Natural Water Samples ◽  
Uptake Process

Nano mint waste (NMW) was used as a low-cost nano biosorbent and efficient Pb(II) remover. pH, contact time, biosorbent dose, and concentration of metal ion were optimized using batch technique to optimize maximum capacity of this new biosorbent. NMW was characterized using FT-IR, SEM, TEM, and XRD analyses. The experimental Pb(II) adsorption data by NMW were agreed with both Freundlich and Langmuir models with maximum boisorption capacity of 2.13 mmolg-1 (441.336 mgg-1). In addition, values of lead uptake at different time vaues was best fitted with the kinetic pseudo-second order model. It will be notable that, good data resulted from the kinetic experiments study confirmed a fast accessibility of the Pb(II) to the biosorbent surface, get to equilibrium within 30 seconds. On the other hand, it was observed that, the developed method, was investigated for measuring of Pb(II) with a certain spiked amounts in natural water samples as ground water (GW), sea water (SW), drinking tap water (DTW), natural drinking water (NDW), Nile River water (NRW) and waste water (WW). The good results obtained with high recovered quantitatively using batch experiments, without matrix interferences. Considering its cheap source, environmentally friendly, economic and fast uptake process, NMW can be used as benign nano biosorbent for lead removal from real water samples.

scholarly journals Diversity, virulence and antibiogram traits of Escherichia coli recovered from potable water sources in Gharbia, Egypt

2020 ◽  
Vol 18 (3) ◽  
pp. 430-438
Author(s):  
Walid Elmonir ◽  
Etab Mohamed Abo Remela ◽  
Yasmine Alwakil
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Water Samples ◽  
Potable Water ◽  
Multiple Drug Resistance ◽  
Tap Water ◽  
Water Sources ◽  
Multiple Drug ◽  
Well Water ◽  
E Coli

Abstract This study aimed to assess the public health risk of coliforms and Escherichia coli contamination of potable water sources in Egypt. A total of 150 water samples (100 tap and 50 well) were collected from five districts in Gharbia governorate, Egypt. High rates of coliforms contamination were recorded in 52 and 76% of examined tap and well water samples, respectively. E. coli strains were detected in 16% of the water samples (15% tap water and 18% well water; 23.7% rural and 8.1% urban). Rural water sources were 3.5 times more likely to be contaminated than urban sources (P = 0.01). Eight (33.3%) E. coli isolates were Shiga toxin-producing E. coli (STEC). Multiple drug resistance (MDR) was observed for 62.5% of the isolates. Seven (29.2%) E. coli isolates harboured at least one of the extended-spectrum beta-lactamase (ESBL) genes. The majority (87.5%) of the STEC isolates were MDRs and harboured ESBL genes. STEC isolates were significantly more likely to resist six classes of antibiotics than non-STEC isolates. This is the first report of potable water contamination with MDR-STEC in Egypt. This study highlights an alarming public health threat that necessitates preventive interventions for public and environmental safety.

Paper-Based Analytical Device for Rapid Naked-Eye Detection of Sulfide in Water Samples

2020 ◽  
Vol 42 (5) ◽  
pp. 696-696
Author(s):  
Lingzhi Zhao Lingzhi Zhao
Keyword(s):  
Water Samples ◽  
Limit Of Detection ◽  
Rapid Determination ◽  
Tap Water ◽  
Low Cost ◽  
Color Intensity ◽  
Detection Zone ◽  
Simulated Waste ◽  
Optimized Conditions ◽  
Analytical Device

This paper describes the development of a low-cost paper-based colorimetric analytical device for the accurate and rapid determination of sulfide. Under optimized conditions, Na2S was dropped in the uptake zone I and the probe in the uptake zone II, they converged to the detection zone via capillary force and formed an intense pink resorufin. Sulfide can be quantified based on the average color intensity values of the product “free resorufin”. The color intensity is recorded using a camera phone, and quantification was made using Adobe Photoshop. The as-developed analytical device detected sulfide in the range of 5–400 μM (R2 = 0.982) with the limit of detection (LOD) 1 μM, and was successfully applied in sulfide assay in spiked water samples including tap water and simulated waste water. Colorimetric results from the proposed paper-based colorimetric analytical device were consistent with that from methylene blue (MB) method.

scholarly journals Chitosan Stabilized Silver Nanoparticles for the Electrochemical Detection of Lipopolysaccharide: A Facile Biosensing Approach for Gram-Negative Bacteria

Micromachines ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 413 ◽  
Author(s):  
Muhammad Imran ◽  
Christopher J. Ehrhardt ◽  
Massimo F. Bertino ◽  
Muhammad R. Shah ◽  
Vamsi K. Yadavalli
Keyword(s):  
Silver Nanoparticles ◽  
Low Cost ◽  
Age Groups ◽  
Single Step ◽  
Indirect Detection ◽  
Detection Methods ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
E Coli ◽  
Strong Electrostatic Interaction

Negatively charged lipopolysaccharide (LPS), a major endotoxin and component of the outer membrane of several Gram-negative bacteria, provides a useful biomarker for the indirect detection of these pathogens. For instance, Escherichia coli (E. coli) is a pathogenic bacterium that causes infections in almost all age groups, and has been implicated in food and water contamination. Current diagnostic and detection methods tend to be labor-intensive or expensive, necessitating the need for an easy, sensitive, rapid, and low-cost method. We report on the synthesis and use of positively charged chitosan stabilized silver nanoparticles (Chi-AgNPs) as a sensitive electrochemical nanobiosensor for the detection of LPS. Chi-AgNPs were synthesized through a facile, single step protocol, and characterized for size, charge, and morphology. Glassy carbon electrodes modified with Chi-AgNPs resulted in an enhancement of signal in the presence of both LPS and E. coli. Detection was accomplished over a large concentration range (several orders of magnitude) of 0.001–100 ng/mL and 10–107 CFU/mL. The biosensors can reliably detect LPS and E. coli at very low concentrations. Chi-AgNPs have potential as low cost, sensitive nanobiosensors for Gram-negative bacteria due to strong electrostatic interaction with LPS present in their outer membranes.

scholarly journals High Fecal Contamination and High Levels of Antibiotic-Resistant Enterobacteriaceae in Water Consumed in the City of Maputo, Mozambique

Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 558
Author(s):  
Acácio Salamandane ◽  
Filipa Vila-Boa ◽  
Manuel Malfeito-Ferreira ◽  
Luísa Brito
Keyword(s):  
Water Samples ◽  
Tap Water ◽  
Fecal Contamination ◽  
Bottled Water ◽  
Fecal Coliforms ◽  
Antibiotic Resistant ◽  
E Coli ◽  
The City ◽  
Klebsiella Spp ◽  
Vibrio Spp

In the city of Maputo, Mozambique, food and water are often sold on the streets. Street water is packaged, distributed, and sold not paying attention to good hygienic practices, and its consumption is often associated with the occurrence of diarrheal diseases. Coincidentally, the increase of diarrheal diseases promotes the inappropriate use of antibiotics that might cause the emergence of antibiotic-resistant bacterial strains. In this context, the present study aimed to assess the microbiological quality of water sold on the streets of Maputo, as well as the antibiotic resistance profile of selected Enterobacteriaceae isolates. The 118 water samples analyzed were from street home-bottled water (n = 81), municipal water distribution systems (tap water) (n = 25), and selected supply wells in several neighborhoods (n = 12). The samples were analyzed for total mesophilic microorganisms, fecal enterococci, fecal coliforms, Escherichia coli, and Vibrio spp. The results showed a high level of fecal contamination in all types of water samples. In home-bottled water, fecal coliforms were found in 88% of the samples, and E. coli in 66% of the samples. In tap water, fecal coliforms were found in 64%, and E. coli in 28% of the samples. In water from supply wells, fecal coliforms and E. coli were found in 83% of the samples. From 33 presumptive Vibrio spp. colonies, only three were identified as V. fluvialis. The remaining isolates belonged to Aeromonas spp. (n = 14) and Klebsiella spp. (n = 16). Of 44 selected Enterobacteriaceae isolates from water samples (28 isolates of E. coli and 16 isolates of Klebsiella spp.), 45.5% were not susceptible to the beta-lactams ampicillin and imipenem, 43.2% to amoxicillin, and 31.8% to amoxicillin/clavulanic acid. Regarding non-beta-lactam antibiotics, there was a high percentage of isolates with tolerance to tetracycline (52.3%) and azithromycin (31.8%). In conclusion, water in Maputo represents a risk for human health due to its high fecal contamination. This situation is made more serious by the fact that a relatively high percentage of isolates with multidrug resistance (40%) were found among Enterobacteriaceae. The dissemination of these results can raise awareness of the urgent need to reduce water contamination in Maputo and other cities in Mozambique.

scholarly journals Bacteriological assessment of tap water collected from different markets of Mymensingh, Gazipur and Sherpur districts of Bangladesh with special focus on the molecular detection and antimicrobial resistance of the isolated Escherichia coli

2018 ◽  
Vol 2 (1) ◽  
pp. 21-28
Author(s):  
Md Shihab Hassan ◽  
SM Lutful Kabir ◽  
Yousuf Ali Sarker ◽  
Md Tanvir Rahman
Keyword(s):  
Antimicrobial Susceptibility ◽  
Water Samples ◽  
Tap Water ◽  
Geometric Mean ◽  
Multidrug Resistant ◽  
Total Coliform ◽  
Plate Count ◽  
Special Focus ◽  
Rrna Gene ◽  
E Coli

The objectives of this study were to assess the bacteriological quality of tap water samples obtained from different markets of different upazillas of Mymensingh, Sherpur & Gazipur district. For achieving the above mentioned objectives, methods of heterotrophic plate count (HPC) and total coliform count (TCC) were applied. Moreover, isolated E. coli from tap water samples were characterized by using biochemical test, molecular method and antimicrobial susceptibility tests. HPC was highest in market tap water collected from Kaligonj and TCC was highest in market tap water of collected from Mymensingh sadar. The geometric mean of HPC of Mymensingh, Gazipur and Sherpur districts water was 8.4x105, 2.5 x106 and 6.8 x105 C.F.U/100 ml. All isolates of E. coli (n=20) were amplified by using 16S rRNA gene based PCR. In respect to antimicrobial susceptibility testing, most of the E. coli isolates were susceptible to norfloxacin, ampicilin, tetracycline, streptomycin and ciprofloxacin. Furthermore, a few E. coli isolates were intermediate resistant to gentamycin and ciprofloxacin. However, a few of the E. coli isolates were resistant to erythromycin and amoxycilin. Moreover, out of 20 E. coli isolates 3 (15%) isolates were detected as multidrug resistant. This study indicated the presence of multidrug resistant E. coli isolates in tap water in Mymensingh, Sherpur and Gazipur districts that warrants particular attention. Asian Australas. J. Food Saf. Secur. 2018, 2(1), 21-28

Fully inkjet-printed distance-based paper microfluidic devices for colorimetric calcium determination using ion-selective optodes

The Analyst ◽  
2019 ◽  
Vol 144 (4) ◽  
pp. 1178-1186 ◽  
Author(s):  
Hiroyuki Shibata ◽  
Yuki Hiruta ◽  
Daniel Citterio
Keyword(s):  
Calcium Ions ◽  
Water Samples ◽  
Tap Water ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Colorimetric Determination ◽  
Naked Eye ◽  
Paper Microfluidic ◽  
Calcium Determination

Fully inkjet-printed and low-cost microfluidic paper-based analytical devices (μPADs) demonstrate the simple naked-eye colorimetric determination of calcium ions in drinking and tap water samples.

scholarly journals Fecal Indicators and Zoonotic Pathogens in Household Drinking Water Taps Fed from Rainwater Tanks in Southeast Queensland, Australia

2011 ◽  
Vol 78 (1) ◽  
pp. 219-226 ◽  
Author(s):  
W. Ahmed ◽  
L. Hodgers ◽  
J. P. S. Sidhu ◽  
S. Toze
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Tap Water ◽  
Fecal Samples ◽  
Content Type ◽  
E Coli ◽  
Zoonotic Pathogens ◽  
Rainwater Tank ◽  
Southeast Queensland ◽  
Rainwater Tanks

ABSTRACTIn this study, the microbiological quality of household tap water samples fed from rainwater tanks was assessed by monitoring the numbers ofEscherichia colibacteria and enterococci from 24 households in Southeast Queensland (SEQ), Australia. Quantitative PCR (qPCR) was also used for the quantitative detection of zoonotic pathogens in water samples from rainwater tanks and connected household taps. The numbers of zoonotic pathogens were also estimated in fecal samples from possums and various species of birds by using qPCR, as possums and birds are considered to be the potential sources of fecal contamination in roof-harvested rainwater (RHRW). Among the 24 households, 63% of rainwater tank and 58% of connected household tap water (CHTW) samples containedE. coliand exceeded Australian drinking water guidelines of <1 CFUE. coliper 100 ml water. Similarly, 92% of rainwater tanks and 83% of CHTW samples also contained enterococci. In all, 21%, 4%, and 13% of rainwater tank samples containedCampylobacterspp.,Salmonellaspp., andGiardia lamblia, respectively. Similarly, 21% of rainwater tank and 13% of CHTW samples containedCampylobacterspp. andG. lamblia, respectively. The number ofE. coli(P= 0.78),Enterococcus(P= 0.64),Campylobacter(P= 0.44), andG. lamblia(P= 0.50) cells in rainwater tanks did not differ significantly from the numbers observed in the CHTW samples. Among the 40 possum fecal samples tested,Campylobacterspp.,Cryptosporidium parvum, andG. lambliawere detected in 60%, 13%, and 30% of samples, respectively. Among the 38 bird fecal samples tested,Campylobacterspp.,Salmonellaspp.,C. parvum, andG. lambliawere detected in 24%, 11%, 5%, and 13% of the samples, respectively. Household tap water samples fed from rainwater tanks tested in the study appeared to be highly variable. Regular cleaning of roofs and gutters, along with pruning of overhanging tree branches, might also prove effective in reducing animal fecal contamination of rainwater tanks.

scholarly journals Prevalence of Legionella spp. and Escherichia coli in the drinking water distribution system of Wrocław (Poland)

2020 ◽  
Vol 20 (3) ◽  
pp. 1083-1090
Author(s):  
M. Wolf-Baca ◽  
A. Siedlecka
Keyword(s):  
Escherichia Coli ◽  
Drinking Water ◽  
Legionella Pneumophila ◽  
Water Samples ◽  
Distribution System ◽  
Water Distribution ◽  
Tap Water ◽  
Potential Threat ◽  
E Coli ◽  
Drinking Water Distribution

Abstract Drinking water should be free from bacterial pathogens that threaten human health. The most recognised waterborne opportunistic pathogens, dwelling in tap water, are Legionella pneumophila and Escherichia coli. Drinking water samples were tested for the presence of Legionella spp., L. pneumophila, and E. coli in overall sample microbiomes using a quantitative real-time polymerase chain reaction (qPCR) approach. The results indicate a rather low contribution of Legionella spp. in total bacteria in the tested samples, but L. pneumophila was not detected in any sample. E. coli was detected in only one sample, but at a very low level. The qacEΔ1 gene, conferring resistance to quaternary ammonium compounds, was also not detected in any sample. The results point to generally sufficient quality of drinking water, although the presence of Legionella spp. in tap water samples suggests proliferation of these bacteria in heating units, causing a potential threat to consumer health.

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