ARTICLE | doi:10.20944/preprints201812.0053.v2
Subject: Life Sciences, Microbiology Keywords: Guadalajara; coliform; intermittent water supply; Colilert, tanks
Online: 21 December 2018 (10:55:39 CET)
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.
ARTICLE | doi:10.20944/preprints201701.0003.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: pito; beverage; bacteria; coliform; Lower Prampram; Ghana
Online: 2 January 2017 (10:55:07 CET)
Pito is a traditionally brewed alcoholic beverage in some African countries. It is gaining much prominence and the patronage among the youth. Therefore, samples of the drink were collected every week for six weeks from three different popular brewing sites at Lower Prampram in the Ningo-Prampram District of Accra, Ghana. The samples were processed and examined for bacteria and fungi using the Standard Plate Count (SPC) technique. A total of six different bacteria and a fungus were isolated. The bacteria were Escherichia coli, Klesiella pneumoniae, Shigella spp, Enterobacter aerogenes, Staphylococcus aureus and Pseudomonas aeroginosa, whiles the fungus was Saccharomyces cerevisiae. Total viable counts as well as individual isolates counts in all the pito samples were found to be less than 104 cfu/ml. It is noteworthy that, Saccharomyces cerevisiae, the only fungus isolated is known to be associated with fermentation and the microbes isolated from the pito samples were found to be within the permissible limits. However, these potentially pathogenic microbes, if found in unacceptable limits, from the fermenting samples could merit public health attention. Therefore, periodic screening of pito and their brewers, coupled with education on the maintenance of recommended guidelines concerning food and drink production is encouraged.
Subject: Engineering, Civil Engineering Keywords: escherichia coli; e. coli; indicator; fecal coliform bacteria; water; bacteriological analysis; fcb; classification
Online: 12 February 2020 (12:12:00 CET)
Escherichia coli or E. coli is a member of the fecal coliform group and is a more specific indicator of fecal contamination than other fecal coliform species, its presence indicate possibly presence of harmful bacteria which will cause diseases and it also suggests the extent as well as the nature of the contaminants. E. coli bacteria able to survive in water for 4 – 12 weeks and at present, it appears as an indicator to provide the accurate bacterial contamination of fecal matter in drinking water, because of the availability of simple, affordable, fast, sensitive and exact detection techniques. According to the laboratory experiment based techniques, 24 - 48 hours are required for the bacterial concentration to be reported. So, there is a necessity for continuous monitoring. Techniques for detection of many pathogenic bacterial strains are not yet available, sometimes days to weeks are required to get the results. To overcome the difficulties, expensive and time-consuming techniques are required to detect, count and identify the presence of specific bacterial strain. Public health relies on online monitoring of water quality that depends majorly on examination of fecal indicator bacteria, thus protection of health requires fecal pollution indicator so that it is not required to analyze drinking water to overcome the problems associated with waterborne diseases. This paper will brief the classification, sources, survival of E. coli bacteria and its correlation with basic water quality parameters in water sources.```
ARTICLE | doi:10.20944/preprints202102.0312.v1
Subject: Life Sciences, Biochemistry Keywords: raw milk stretched cheeses; lactic acid bacteria; coliform bacteria; Escherichia coli; Staphylococcus aureus; yeasts and moulds
Online: 12 February 2021 (15:26:35 CET)
To evaluate the behaviour of the relevant microbial populations during stretched cheese production, the quantitative microbiological analysis was performed during the critical steps of the preparation. The obtained data distributions proved statistically significant increases in all indicators, on average by 4.55 ± 0.64 log CFU/g of presumptive lactococci counts, 4.06 ±0.61 of lactobacilli, 1.53 ± 0.57 log CFU/g of coliforms, 2.42 ± 0.67 log CFU/g of Escherichia coli, 1.53 ± 0.75 log CFU/g of yeasts and moulds, and 0.99 ± 0.27 log CFU/g of presumptive Staphylococcus aureus, from the early stage of milk coagulation until curd ripening (0–24 h). The following steaming/stretching process caused reductions in viable counts with the most significant inactivation effect on coliform bacteria, including E. coli (-4.0 ± 1.0 log CFU/g). Total viable counts and yeasts and moulds showed 2 and almost 3 log reduction (-2.2 ± 1.1 log CFU/g and -2.6 ± 0.9 log CFU/g), respectively. The lowest decreases in presumptive S. aureus counts were estimated at the level of -1.50 ± 0.64 log CFU/g. The counts of yeasts and moulds showed the best indicatory function during the entire storage period of vacuum-packaged cheeses at 6 °C.