scholarly journals Use of the ISO 9308-1 procedure for the detection of E. coli in water utilizing two incubation temperatures and two confirmation procedures and comparison with defined substrate technology

2008 ◽  
Vol 6 (3) ◽  
pp. 389-397 ◽  
Author(s):  
C. R. Fricker ◽  
S. Bullock ◽  
K. Murrin ◽  
S. I. Niemela

Disinfected and non-disinfected samples have been used to determine the accuracy of the ISO procedure (ISO 9308-1) for detection of E. coli in drinking water. Samples were analysed using the ISO procedure at both 36 and 44°C and using the defined substrate technology method Colilert-18®/Quanti-Tray® (Colilert-18). Utilizing the confirmation procedure described in ISO 9308-1, large numbers of false positive E. coli results were obtained using the ISO primary isolation procedure at 36°C. However, when glucuronidase production was used as the confirmation procedure, the ‘confirmed’ count of E. coli was lowest with ISO 9308-1 performed at 36°C. When TTC medium was incubated at 36°C confirmation using production of indole at 44°C resulted in 29% more ‘E. coli’ being recovered than when confirmation was performed using production of glucuronidase. When 44°C was used as the primary isolation temperature the difference between the number of ‘confirmed’ E. coli identified using the two confirmation procedures was less than 1% and was not significant. Identification of isolates which ‘confirmed’ when using production of indole at 44°C as the test method but °which failed to produce β-D-glucuronidase, showed that the majority of these isolates were Klebsiella oxytoca.

2020 ◽  
Vol 12 (2) ◽  
pp. 124-9
Author(s):  
Juminten Saimin ◽  
Hartati Hartati ◽  
Yenti Purnamasari ◽  
Sufiah Asri Mulyawati ◽  
Tien Tien ◽  
...  

BACKGROUND: The access to safe drinkingwater is increasingly difficult, especially in water catchment or coastal areas. Due to the difficulty, people in coastal areas tend to consume ready-to-use refilled drinking-water. However, the sanitation facilities on most drinking-water refill depots do not meet the requirements, hence really prone to microbial contamination. We conducted this study to determine the types of bacteria causing the contamination of refilled drinking-water from refill depots in Abeli, a coastal area in Kendari.METHODS: Samples were collected from all 6 drinkingwater refill depots in Abeli. Three-series fermentation tubes were used for the microbiological test, including the presumptive, confirmative and completed tests. The biochemical test was performed with indole test, methyl red test, Voges-Proskauer test, and citrate utilization test (IMViC) methods and the triple sugar iron agar (TSIA) test.RESULTS: Among 6 refilled drinking-water samples, we found the growth of coliform bacterial colonies in 3 samples, exhibiting various characteristics. Based on the characteristics, both microbiological and biochemical, the identified bacteria were Proteus sp., Escherichia coli and Klebsiella oxytoca.CONCLUSION: Bacteria that contaminated refilled drinking-water in Abeli were Proteus sp., E. coli and K. oxytoca. Continuous supervision is required to ensure the quality of water from drinking-water refill depots.KEYWORDS: bacteria, Proteus sp., Escherichia coli, Klebsiella oxytoca, coastal areas, refilled drinking water


2014 ◽  
Vol 15 (1&2) ◽  
pp. 99-107
Author(s):  
G.V Zodape

14 drinking water samples were collected from Vile Parle to Dadar of Suburban’s of (P-South ward offices of B.M.C (Bombay Municipal Corporation) Mumbai in the month from June to December 2012. The samples of drinking-water were analyzed for Cu, Zn, Mn, Fe, As, Cr, Ni, Pb, Cd and Hg. From the results so obtained, the contamination due to heavy metals – Zn (3.115 ppm and 7.816 ppm), Mn (3.115 ppm and 7.426 ppm), Fe (1.124 ppm and 2.872 ppm), As (0.011 ppm to 0.091 ppm), Cr (0.188 ppm and 0.998 ppm ), Pb (1.587 ppm and 4.56 ppm) and Cd (0.011 ppm and 0.051 ppm ) was found to be high whereas the contamination due to Cu (0.012 ppm and 0.313 ppm), Ni (0.126 ppm and 0.774 ppm), were found below the acceptable limits and no Hg was detected in the samples of drinking-water. In the present work, MacConkey Broth was used as a differential medium for detection and enumeration of coliforms from a wide variety water samples. The presence of positive doubtful presumptive test immediately suggests that the water is non potable (i.e., both acid and gas develops in a tube after 48 hours incubation). Confirmation suggests that there is fecal contamination in the water under investigation and hence it is non potable. All the fourteen samples (streaked from positive Ma cConkey broth tubes) were found to be contaminated with E. coli, which was further confirmed by the presence of colonies with green metallic sheen observed under a microscope confirmed that the said samples were contaminated with E. coli - the major indicator of fecal contamination.


Author(s):  
Ehssan H. Moglad ◽  
Omima Abdl El Jalil Adam ◽  
Maram M. Alnosh ◽  
Hisham N. Altayb

Abstract This study aimed to determine the prevalence of virulence genes in all the diarrheagenic Escherichia coli DEC strains (EAEC, EHEC, EIEC, EPEC, and ETEC) isolated from drinking water from Khartoum State, Sudan. A total of 46 drinking water samples obtained from different water sources were analyzed for the presence of E. coli as fecal contamination indicator and the antimicrobial-resistant pattern of isolated E. coli DEC strain was investigated. The bacterial genomic DNA was used as a template for multiplex polymerase chain reaction (MPCR) for the detection of the EHEC (stx gene), EIEC (ipaH gene), EPEC (eae gene), and EAEC (aggR gene) as virulence and biomarker genes. Our results showed that ipaH gene was found in 41.3% (19/46) of isolates, and aggR gene detected in 30.4% (14/46) of isolates. Both aggR and ipaH were found positive in 9 (19.5%) isolates and as well the combination of aggR and stx genes were detected in 2 (4.3%) isolates. In conclusion, this report confirmed the presence of DEC strains in drinking water from different resources and locations. Such findings require separate future clinical research studies to examine waterborne pathogens that exist in this state's water and find a management solution to stop or avoid potential outbreaks.


2020 ◽  
Vol 103 (5) ◽  
pp. 1348-1360
Author(s):  
Tam L Mai ◽  
Ziwen Ming ◽  
Van Nguyen ◽  
Anna Shapovalova ◽  
Mansour Samadpour

Abstract Background The Enterobacteriaceae and generic Escherichia coli are routinely enumerated in foods as part of product release criteria, or in the case of swabs, for environmental monitoring. Objective Microbiologique Microfilm™ EBEc is intended to provide a rapid and easy-to-use method for simultaneous enumeration of Enterobacteriaceae and E. coli on foods and environmental surfaces. Methods: This study evaluated the performance of Microfilm™ EBEc against ISO methods (ISO 21528-2:2017 for Enterobacteriaceae and ISO 16649-2: 2001 for E. coli) in 20 food matrixes and two environmental surfaces. Inclusivity, exclusivity, lot-to-lot reproducibility, ruggedness and stability studies were also performed on Microfilm™ EBEc. Results No significant differences and high correlation coefficients (R2) were observed between the Microfilm™ EBEc and the corresponding ISO methods in spiked food matrixes and environmental samples. Inclusivity studies showed expected results for all the E. coli and Enterobacteriaceae strains tested. In terms of exclusivity testing, all the strains tested failed to grow on Microfilm™ EBEc. A lot-to-lot study showed no significant differences in mean difference (log10) counts among the three lots of the Microfilm™ EBEc. Ruggedness studies showed no significant differences in mean difference (log10) counts at varying incubation temperatures and times. Stability studies on the Microfilm™ EBEc showed that it is stable at 2–25°C for 12 months, and at 45°C for 6 weeks. Conclusions The results of this study indicate that the Microfilm™ EBEc is equivalent to the corresponding ISO methods for enumeration of Enterobacteriaceae and E. coli. Highlights: Microfilm™ EBEc offers a convenient and relatively fast test method for simultaneous enumeration of Enterobacteriaceae and E. coli in 24 h and has an advantage over the corresponding ISO methods that require two assays on the same sample for enumeration of Enterobacteriaceae and E. coli Gram-negative indicator groups.


2013 ◽  
Vol 12 (1) ◽  
pp. 113-121 ◽  
Author(s):  
Robert L. Matthews ◽  
Rosalind Tung

Microbiological testing is an integral part of measures to ensure safe drinking water. However, testing can be restricted in low-resource settings by the requirement for specialized laboratory facilities and testing procedures. Precisely controlled incubation temperature is one example. The effect of varied incubation temperatures on the performance of two enzyme substrate tests for the detection of Escherichia coli and total coliforms has been examined. The aim was to determine whether these tests would provide consistent and comparable enumeration over a broader temperature range than currently specified. Recovery of chlorine-injured and wild type E. coli was examined over a range of non-standard incubation temperatures in comparison to 37 °C ± 1. Colilert® and Aquatest, a new E. coli-specific detection medium, served as the two representative enzyme substrate media. Recovery of chlorine-injured E. coli in Colilert was not impaired within the range 33–39 °C; the equivalent range in Aquatest medium was 31–43 °C. Both these tests recovered E. coli without significant loss of performance over a wider range of temperatures than currently specified.


Jurnal BIOMA ◽  
2017 ◽  
Vol 11 (1) ◽  
pp. 73
Author(s):  
Rezki Rachmawati ◽  
Muzajjanah Muzajjanah ◽  
Yoswita Rustam

Refill Water Depot is currently more widely circulated and used as an alternative drinking water supply by the public. However the still unclear about the quality of the drinking water refill generated primarily of biological content. Parameters of biological contamination in drinking water caused by the Escherichia coli and coliform bacterium. This study aims to identify E. coli and coliforms in drinking water refill. Refill drinking water samples obtained from 16 drinking water refill from Jagakarsa subdsitrict. The method used is descriptive. Refill drinking water samples was taken and tested in the MPN (Most Probable Number) method and then to be tested in identification of E. coli. The results of testing the drinking water refill obtained 15 samples positive for coliform bacteria. Samples were positive for E. coli bacteria that sample B.1 and F.2.


2016 ◽  
Vol 6 (2) ◽  
pp. 224-230
Author(s):  
S. G. D. N. Lakshmi Reddi ◽  
R. Naveen Kumar ◽  
G. M. SubbaRao ◽  
M. Vishnu Vardhana Rao ◽  
R. V. Sudershan

Quality of water for consumption and food processing activities is universally accepted as an essential component to ensure food safety at household (HH) level. Along with safe water, hand hygiene is also an important factor for reducing diarrheal illnesses. This was a cross-sectional study conducted in rural and urban HHs to detect hygiene indicators in drinking water samples at point of use (PoU) (n = 150) and their association with the hand hygiene of primary food preparers (n = 150). Overall, 24.7% and 9.3% of drinking water samples (PoU), 48% and 20% of hand rinse samples were contaminated by faecal coliforms and E. coli, respectively. Both drinking water (PoU) and hand rinse samples collected from rural HHs showed higher contamination, followed by those from urban slums and low income HHs. Significant association (p < 0.05) and probable risk with faecal coliforms (OR. 2.5; 95% CI: 1.1–5.4) and E. coli (OR. 14.5; 95% CI: 4.1–50.7) was found between hand rinses and drinking water samples that had bacteriological contamination. These results suggest that there was an extensive cross contamination at HH level. So, targeted education is essential on safe food/water handling practices in HHs to prevent food safety risks.


Author(s):  
Yunita Rusidah ◽  
Lailatul Farikhah

This study is intended to find the quality of bottled drinking water (AMDK) and drinking water (AMIU) sold around University of Muhammadiyah Kudus, in terms of organoleptic and microbiological parameters in drinking water according to SNI 01-3554-2006 and PMK No. 492 of  2010. The test is carried out using 10 sample of drinking water. They are 7 sample of AMDK (Ades, Airmu, Aqua, Cleo, Crystalin, Le mineral and Vit) and 3 sample of AMIU (Pasuruhan, Prambatan and Purwosari depots). The research consists of organoleptic and  mikrobiologi (TPC, presence of E. coli and total coliform). The results of research shows that the organoleptik of all samples is in normal condition. Whereas, microbiologically, the TPC results before dilution were only Cleo and Ades which were suitable for consumption because they were absent from bacterial contamination. While the TPC results after dilution, testing the difference between E. Coli and Total coliform resulted in 7 samples of bottled drinking water which were safe and feasible as drinking water according to SNI 01-3553-2006 and 3 samples AMIU does not fulfil PMK No. 492/2010, as drinking water requirements.


2021 ◽  
Vol 10 (1) ◽  
pp. 23
Author(s):  
Muhammad Rayhan Braja Gitawama ◽  
Netti Suharti ◽  
Nora Harminarti

The National Food and Drug Agency has controlled the refill drinking water in drinking water depots and also controlled food at school canteens ranging from elementary, junior high, to high school, but the National Food and Drug Agency never do food quality controlling in canteens at universities. Objectives: To identified the contamination by coliform and E. coli bacteria in drinking water at Andalas University canteen. Methods: This research was descriptive to identify coliform bacteria on  15 drinking water at the Andalas University faculty canteens.  Samples were taken directly using a sterile bottle, while data analysis using Most Probable Number  (MPN)  tables 5-1-1 and the presence of E. coli bacteria colonies from drinking water samples. Results: 9 of 15 water samples were contaminated by coliform bacteria with the highest MPN index of 240/100 ml that was found in 2 samples. From 9 samples containing coliform bacteria, all of them were found to contain E. coli bacteria. Conclusion: Most of the samples were contaminated by coliform and E. coli bacteria. Drinking water served using a kettle was more contaminated than drinking water served using gallons.Keywords: Coliform, Escherichia coli, MPN


Sign in / Sign up

Export Citation Format

Share Document