Identification of strains isolated as total and fecal coliforms and comparison of both groups as indicators of fecal pollution in tropical climates

1983 ◽  
Vol 29 (6) ◽  
pp. 689-693 ◽  
Author(s):  
Marc C. Lavoie

This study was undertaken to better characterize the groups of total coliforms (TC) and fecal coliforms (FC) and to evaluate both groups as indicators of fecal contamination of drinking well water in a tropical climate (The Ivory Coast, West Africa). Isolated colonies obtained as TC or FC on membrane filters were identified using the API-20E system. From the well water samples, 58 golden-green colonies with a metallic sheen isolated on Endo medium (TC) were identified as Escherichia coli (55%), Enterobacter (26%), Klebsiella (14%), Proteus (3%), and Citrobacter (2%). Among 132 colonies isolated on Endo medium as non-TC (not showing the characteristic golden metallic sheen), 10% were identified as E. coli. The 196 blue colonies isolated on M-FC medium at 44.5 °C (FC) were identified as E. coli (66%), Klebsiella (12%), Enterobacter (10%), Citrobacter (5%), Salmonella (3%), Serratia (3%), Proteus (2%), and Yersinia (0.5%). Among 24 nonblue colonies on M-FC medium, none were identified as E. coli. Of the colonies isolated from human feces, E. coli represents 92% of the TC and 89% of the FC. Although these results are limited, they tend to confirm the greater specificity of the fecal coliform technique over that of total coliform for the detection of fecal contamination of untreated well water. From the results presented here and the observations of other workers, it is suggested that the use of FC instead of TC should be considered as the method of choice for determining drinking water pollution of untreated groundwater supplies.

1995 ◽  
Vol 31 (12) ◽  
pp. 239-248 ◽  
Author(s):  
Ana Emparanza-Knörr ◽  
Francisco Torrella

The Salmonella presence and the microbiological quality indicators, total and fecal coliforms and coliphages of E. coli C, have been studied in a overloaded wastewater lagoon system treating urban wastewatrers of the village of Guardamar del Segura (Alicante, Spain). Classical microbiological technology to detect salmonellae was used, including pre-enrichment, enrichment, selective media plating and biochemical and serological confirmation. Water was physicochemically characterized according to COD, SS, temperature, pH and dissolved oxygen. The selective migration step through Rappaport-Vassiliadis semisolid agar medium was essential for the consistent detection of Salmonella in the different lagoon effluents. Total and fecal coliform levels of up to 105-106 MPN/100 ml were detected in the final effluent. High coliphage concentrations of 103-104 pfu/ml were also found in the effluent waters. Salmonella was always detected in 100 ml samples and eventually reached an order of value of 103 MPN/100 ml. Total coliform reduction was higher in the anaerobic ponds whereas fecal coliforms were more efficiently eliminated in the facultative (mostly “anoxic”) lagoons. Coliphage reduction was higher in the facultative lagoons when compared to the anaerobic ponds. On many occasions, no reduction or eventual increment of the concentration of salmonellae was detected in the effluents from the anaerobic ponds compared to concentrations of the patohogen in the influent raw wasterwaters. The possibility exists for a capacity of Salmonella to multiply in the anoxic phase of the wastewater treatment, but the presence of microorganisms in raw sewage waters which could maskSalmonella detection with the enrichment methodology employed cannot be ruled out.


1993 ◽  
Vol 39 (10) ◽  
pp. 973-977 ◽  
Author(s):  
Allen N. Hagler ◽  
Carlos A. Rosa ◽  
Paula B. Morais ◽  
Leda C. Mendonça-Hagler ◽  
Georgia M. O. Franco ◽  
...  

Yeasts and coliform bacteria were isolated from water that accumulated in the central cups and adjacent leaf axilae of two bromeliads, Neoregelia cruenta of a coastal sand dune and Quesnelia quesneliana of a mangrove ecosystem near the city of Rio de Janeiro, Brazil. The mean total coliform counts were above 10 000 per 100 mL for waters of both plants, but the mean fecal coliform counts were only 74 per 100 mL for Q. quesneliana and mostly undetected in water from N. cruenta. Of 90 fecal coliform isolates, 51 were typical of Escherichia coli in colony morphology and indol, methyl red, Volges–Proskauer, and citrate (IMViC) tests. Seven representatives of the typical E. coli cultures were identified as this species, but the identifications of nine other coliform bacteria were mostly dubious. The yeast community of N. cruenta was typical of plant surfaces with basidiomycetous yeasts anamorphs, and the black yeast Aureobasidium pullulans was prevalent. Quesnelia quesneliana had a substantial proportion of ascomycetous yeasts and their anamorphs, including a probable new biotype of Saccharomyces unisporus. Our results suggested that the microbial communities in bromeliad waters are typically autochtonous and not contaminants.Key words: yeasts, fecal coliforms, bromeliad waters, mangrove, Restinga.


2002 ◽  
Vol 68 (4) ◽  
pp. 1631-1638 ◽  
Author(s):  
A. Leclercq ◽  
C. Wanegue ◽  
P. Baylac

ABSTRACT A 24-h direct plating method for fecal coliform enumeration with a resuscitation step (preincubation for 2 h at 37 ± 1°C and transfer to 44 ± 1°C for 22 h) using fecal coliform agar (FCA) was compared with the 24-h standardized violet red bile lactose agar (VRBL) method. FCA and VRBL have equivalent specificities and sensitivities, except for lactose-positive non-fecal coliforms such as Hafnia alvei, which could form typical colonies on FCA and VRBL. Recovery of cold-stressed Escherichia coli in mashed potatoes on FCA was about 1 log unit lower than that with VRBL. When the FCA method was compared with standard VRBL for enumeration of fecal coliforms, based on counting carried out on 170 different food samples, results were not significantly different (P > 0.05). Based on 203 typical identified colonies selected as found on VRBL and FCA, the latter medium appears to allow the enumeration of more true fecal coliforms and has higher performance in certain ways (specificity, sensitivity, and negative and positive predictive values) than VRBL. Most colonies clearly identified on both media were E. coli and H. alvei, a non-fecal coliform. Therefore, the replacement of fecal coliform enumeration by E. coli enumeration to estimate food sanitary quality should be recommended.


1980 ◽  
Vol 43 (2) ◽  
pp. 111-113 ◽  
Author(s):  
MARK D. SOBSEY ◽  
CAMERON R. HACKNEY ◽  
ROBERT J. CARRICK ◽  
BIBEK RAY ◽  
MARVIN L. SPECK

Enteric bacteria and virus levels were determined in oysters from paired stations that were opened or closed for commercial shellfishing on the basis of total coliform levels in the water. Six pairs of stations were sampled quarterly over a 1-year period. Enteric viruses were found in 3 of 24 50-g oyster samples from closed areas and in none of 23 samples from open areas. Salmonella was found in 2 of 47 samples of 40 g each, one from an open and the other from a closed area. Although enteric pathogens of fecal origin were found only in oysters that exceeded the recommended market limit of 230 fecal coliforms per 100 g of meat, the fecal coliform levels in some virus-positive samples were much lower than those in Salmonella-positive samples. Vibrio parahemolyticus levels were similar in oysters from both open and closed beds, indicating no particular association with fecal pollution. However, there was a marked seasonal variation in V. parahemolyticus levels. Total but not fecal coliform levels in oysters from open beds correlated with the occurrence of rainfall 1 or 2 days before sample collection. Neither total nor fecal coliform levels in oysters from closed beds correlated with rainfall. These findings suggest that fecal coliforms levels in oysters are less influenced by rainfall than are total coliforms, and therefore may be a more specific indicator of recent fecal pollution.


2007 ◽  
Vol 73 (12) ◽  
pp. 3771-3778 ◽  
Author(s):  
Winfried B. Ksoll ◽  
Satoshi Ishii ◽  
Michael J. Sadowsky ◽  
Randall E. Hicks

ABSTRACT Epilithic periphyton communities were sampled at three sites on the Minnesota shoreline of Lake Superior from June 2004 to August 2005 to determine if fecal coliforms and Escherichia coli were present throughout the ice-free season. Fecal coliform densities increased up to 4 orders of magnitude in early summer, reached peaks of up to 1.4 � 105 CFU cm−2 by late July, and decreased during autumn. Horizontal, fluorophore-enhanced repetitive-PCR DNA fingerprint analyses indicated that the source for 2% to 44% of the E. coli bacteria isolated from these periphyton communities could be identified when compared with a library of E. coli fingerprints from animal hosts and sewage. Waterfowl were the major source (68 to 99%) of periphyton E. coli strains that could be identified. Several periphyton E. coli isolates were genotypically identical (≥92% similarity), repeatedly isolated over time, and unidentified when compared to the source library, suggesting that these strains were naturalized members of periphyton communities. If the unidentified E. coli strains from periphyton were added to the known source library, then 57% to 81% of E. coli strains from overlying waters could be identified, with waterfowl (15 to 67%), periphyton (6 to 28%), and sewage effluent (8 to 28%) being the major potential sources. Inoculated E. coli rapidly colonized natural periphyton in laboratory microcosms and persisted for several weeks, and some cells were released to the overlying water. Our results indicate that E. coli from periphyton released into waterways confounds the use of this bacterium as a reliable indicator of recent fecal pollution.


2015 ◽  
Vol 78 (3) ◽  
pp. 567-572 ◽  
Author(s):  
ANURADHA GHOSH ◽  
LUDEK ZUREK

House flies are a common pest at food animal facilities, including cattle feedlots. Previously, house flies were shown to play an important role in the ecology of Escherichia coli O157:H7; house flies in cattle feedlots carried this zoonotic pathogen and were able to contaminate cattle through direct contact and/or by contamination of drinking water and feed. Because house flies aggregate in large numbers on fresh (≤6 h) steam-flaked corn (FSFC) used in cattle feed, the aim of this study was to assess FSFC in a cattle feedlot as a potentially important site of fecal coliform contamination by house flies. House flies and FSFC samples were collected, homogenized, and processed for culturing of fecal coliforms on membrane fecal coliform agar. Selected isolates were identified by 16S rRNA gene sequencing, and representative isolates from each phylogenetic group were genotyped by pulsed-field gel electrophoresis. Fecal coliforms were undetectable in FSFC shortly (0 h) after flaking; however, in summer, after 4 to 6 h, the concentrations of fecal coliforms ranged from 1.9 × 103 to 3.7 × 104 CFU/g FSFC (mean, 1.1 ± 3.0 × 104 CFU/g). House flies from FSFC carried between 7.6 × 102 and 4.1 × 106 CFU of fecal coliforms per fly (mean, 6.0 ± 2.3 × 105 CFU per fly). Fecal coliforms were represented by E. coli (85.1%), Klebsiella spp. (10.6%), and Citrobacter spp. (4.3%). Pulsed-field gel electrophoresis demonstrated clonal matches of E. coli and Klebsiella spp. between house flies and FSFC. In contrast, in winter and in the absence of house flies, the contamination of corn by fecal coliforms was significantly (~10-fold) lower. These results indicate that FSFC is an important site for bacterial contamination by flies and possible exchange of E. coli and other bacteria among house flies. Further research is needed to evaluate the potential use of screens or blowers to limit the access of house flies to FSFC and therefore their effectiveness in preventing bacterial contamination.


1976 ◽  
Vol 39 (5) ◽  
pp. 322-324 ◽  
Author(s):  
W. H. ANDREWS ◽  
C. D. DIGGS ◽  
J. J. MIESCIER ◽  
C. R. WILSON ◽  
W. N. ADAMS ◽  
...  

To determine the relationship of most probable number (MPN) of the total and fecal coliform groups in shellfish and shellfish-growing waters to the presence of Salmonella in quahaugs (Mercenaria mercenaria), a microbiological survey of 214 samples of the quahaug, or hard-shell clam, was done over 24 months. For purposes of this study, waters were classified as safe for shellfish harvesting by one of two criteria: (a) a total coliform MPN of ≤ 70/100 ml of water or (b) a fecal coliform MPN value of ⩽ 14/100 ml of water. None of the quahaug samples harvested from waters meeting these standards contained Salmonella. Additionally, Salmonella was not detected in any of the quahaug samples meeting the wholesale market quality standard of 230 fecal coliforms per 100 g of shellfish as specified by the National Shellfish Sanitation Program. An increase in the total coliform and fecal coliform MPN of the waters more closely paralleled an increase in the fecal coliform MPN, as compared to the total coliform MPN of the quahaug meats. Five Salmonella serotypes, including Salmonella parathyphi B, were found singly and in combination in five (2.3%) of the quahaug samples in this survey.


2018 ◽  
Vol 17 (2) ◽  
pp. 25-31 ◽  
Author(s):  
Bikram Gautam ◽  
Rameshwar Adhikari

Introduction: Membrane filtration (MF) is one of the widely used technique on a routine basis. On the other hand, replica plate (RP) technique can be used to transfer existing bacterial colonies in two plates which even allows pinpointing the original colony. The aim of this study is to comparatively detect the cfu/100 mL of fecal coliform using membrane filtration and replica plate techniques.Methods: In the study, a total of 25 bottled water were selected from the local market in Kathmandu valley. The total coliform count was detected using MF, while fecal coliform was detected using both MF and RP technique.Results: It was found that the average cfu/100 mL for total coliform, fecal coliform (MF) and fecal coliform (RP) were 143.38, 49.82 and 51.00 respectively. Pearson correlation coefficient calculated between total coliform and fecal coliform (MF), total coliform and fecal coliform (RP), fecal coliform (MF) and fecal coliform (RP) were found to be 0.695, 0.733 and 0.990 respectively; implying a positive correlation Conclusions: It has been demonstrated that intrinsic and extrinsic factors influence colony forming units. Furthermore, RP is a more sensitive method for screening fecal coliforms although both MF and RP can be efficiently used.


2017 ◽  
Vol 1 (2) ◽  
pp. 35-36
Author(s):  
Bariza Gourari ◽  
Djamel Anteur

Background: Freshwater fish play a role in detoxification of certain germs and pathogens of bacteria. Variation of the content of pathogenic bacteria are, mainly, total coliform, fecal coliform, and fecal streptococci in the study sites of the sampling period. The objective of this study is inventoried purifying species of dam of Ain Zada. Methods: The isolation of fecal coliform (CF) and total coliform (CT) was conducted by incorporation in agar of the five shot test (0,4 mL; 1 mL et 3 x 2 mL). The culture medium is the selective agar Mac Conkey (HIMEDIA, M083) coliforms. The enumeration of the colonies is done after 24 of incubation at 37°C for total coliforms and 44°C for fecal coliforms. The isolation of fecal streptococci (SF) is made by the same method but on the culture medium incubated at 37°C for 48 hours. Counting of colonies is done on mailboxes where 100 to 300 colonies are developed. The average of colonies counted is then determined. The boxes do not contain at least 100 colonies, all of the colonies on all boxes are counted, taking into account the total volume inoculated in water. In the second part, there is an inventory of purifying fish at the Ain Zada dam level. Results: The result indicate that all the fish that play a role in the treatment of dam of Ain Zada (Bordj Bou Arreridj) who use these germs and bacteria as a food source. We registered the presence of a single family, with five (05) genera divided into seven (07) species, including the majority of alien species are Cyprinid fish: Sander lucioperca L., Ctenopharyngodon idella, Clarias gariepinus, Cyprinus carpio, Hypophthalmichthys molitrix and Hypophtalmichthys nobilis. Conclusion: The Bousselam and Ouricia valleys feature heavily poor microbiological quality; exploitation of these waters could constitute a health hazard on dam Ain Zada. According to this study, the fish play a role of biological control.


Author(s):  
Farhan Mohammad Khan ◽  
Rajiv Gupta

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.```


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