Enumeration and Identification of Coliform Bacteria Injured by Chlorine or Fungicide Mixed with Agricultural Water

2016 ◽  
Vol 79 (10) ◽  
pp. 1789-1793 ◽  
Author(s):  
HIDEMI IZUMI ◽  
YUJI NAKATA ◽  
AYANO INOUE
Keyword(s):  
Cell Injury ◽  
Pond Water ◽  
Coliform Bacteria ◽  
Agricultural Water ◽  
Isolation And Identification ◽  
Electrolyzed Water ◽  
Selective Media ◽  
E Coli ◽  
Pure Cultures ◽  
Water Pond

ABSTRACT Chemical sanitizers may induce no injury (bacteria survive), sublethal injury (bacteria are injured), or lethal injury (bacteria die). The proportion of coliform bacteria that were injured sublethally by chlorine and fungicide mixed with agricultural water (pond water), which was used to dilute the pesticide solution, was evaluated using the thin agar layer (TAL) method. In pure cultures of Enterobacter cloacae, Escherichia coli, and E. coli O157:H7 (representing a human pathogen), the percentage of chlorine-injured cells was 69 to 77% for dilute electrolyzed water containing an available chlorine level of 2 ppm. When agricultural water was mixed with electrolyzed water, the percentage of injured coliforms in agricultural water was 75%. The isolation and identification of bacteria on TAL and selective media suggested that the chlorine stress caused injury to Enterobacter kobei. Of the four fungicide products tested, diluted to their recommended concentrations, Topsin-M, Sumilex, and Oxirane caused injury to coliform bacteria in pure cultures and in agricultural water following their mixture with each pesticide, whereas Streptomycin did not induce any injury to the bacteria. The percentage of injury was 45 to 97% for Topsin-M, 80 to 87% for Sumilex, and 50 to 97% for Oxirane. A comparison of the coliforms isolated from the pesticide solutions and then grown on either TAL or selective media indicated the possibility of fungicide-injured Rahnella aquatilis, Yersinia mollaretii, and E. coli. These results suggest the importance of selecting a suitable sanitizer and the necessity of adjusting the sanitizer concentration to a level that will kill the coliforms rather than cause sanitizer-induced cell injury that can result in the recovery of the coliforms.

A Charcoal- and Blood-Free Enrichment Broth for Isolation and PCR Detection of Campylobacter jejuni and Campylobacter coli in Chicken†

2011 ◽  
Vol 74 (2) ◽  
pp. 221-227 ◽  
Author(s):  
LUISA Y. SOLÍS-SOTO ◽  
SANTOS GARCÍA ◽  
IRENE WESLEY ◽  
NORMA HEREDIA
Keyword(s):  
Campylobacter Jejuni ◽  
Attractive Alternative ◽  
Campylobacter Coli ◽  
Pcr Assay ◽  
Isolation And Identification ◽  
Enrichment Broth ◽  
E Coli ◽  
Chicken Skin ◽  
Pure Cultures ◽  
Free Enrichment

The microaerophilic nature of Campylobacter and its requirement of ~5% O2 for growth have complicated its recovery from foods. The addition to the enrichment media of oxygen quenchers such as charcoal or blood could interfere with PCR for its detection. In this study, a two-step simple aerobic method for Campylobacter detection is proposed. A modification of the Tran blood-free enrichment broth (BFEB), in which charcoal was excluded from the medium (M-BFEB), was compared with the original formulation and other enrichment broths. Campylobacter jejuni and Campylobacter coli were screened by PCR directly from the enrichment media. Various levels of pure cultures of C. jejuni and C. coli combined with Escherichia coli were inoculated into Preston, Bolton, BFEB, and the modified BFEB (M-BFEB). In addition, Campylobacter was inoculated onto retail purchased chicken skin and recovery was quantified. Rates of recovery after 24 to 48 h of enrichment at 42°C under aerobic incubation for BFEB and M-BFEB and microaerobic incubations for Preston and Bolton broths were determined. Overall, our results indicated that the most sensitive medium was Bolton's, followed by either BFEB or M-BFEB; the least sensitive was Preston's. M-BFEB was directly coupled to a PCR assay to detect Campylobacter, avoiding intermediate plating. Campylobacter was detected in the presence of up to108 E. coli cells per ml. M-BFEB facilitated detection of both C. jejuni and C. coli artificially inoculated onto chicken skin samples. M-BFEB coupled to PCR is a rapid and attractive alternative for isolation and identification of C. coli and C. jejuni from poultry.

scholarly journals Isolation and Identification of Bacteria Responsible for the Spoilage of Fluted Pumpkin (Telfaria occidentalis) and Bitter Leaf (Vernonia amygdalina) in Sokoto Metropolis

2021 ◽  
pp. 372-378
Author(s):  
A.S. Muhammad ◽  
S.A. Ani ◽  
A.M. Nasiru
Keyword(s):  
Proteus Mirabilis ◽  
Biochemical Test ◽  
Gram Stain ◽  
Vernonia Amygdalina ◽  
Isolation And Identification ◽  
E Coli ◽  
Percentage Distribution ◽  
Fluted Pumpkin ◽  
Urease Test ◽  
Pure Cultures

The research was conducted in 2016 at the Microbiology Laboratory in the Department of Microbiology in Usmanu Danfodiyo University Sokoto. The main objective was to isolate and identify those bacteria responsible for the spoilage of bitter leaf (Vernonia amygdalina) and fluted pumpkin (Telfairia occidentalis). This approach presented extracting these bacteria form the vegetables and then culture then on agar plates, colonies were formed and subcultures on different plates, pure cultures were obtained and cultured in slant bottles containing nutrient agar for identification through biochemical test bacterial utilization of substrates which include Triple sugar ion, Methyl red and Vogues prosturer test, starch hydrolysis, Indole, citrate, catalase, urease test and recorded. Gram stain was carried out to identify the gram reaction and viewed under microscope for cell morphology. Bacteria species of the stock culture were identified using Atlas Book of Bacteria using the biochemical test results and gram stain reactions, the bacteria isolated were identified as gram negative rod bacteria. Percentage distribution of occurrence showed that E. coli had had the highest frequency of occurrence with percentage distribution of 42.8% in bitter leaf, followed by Proteus mirabilis, and B. cereus both having 28.6% respectively. Proteus mirabilis had 50% in fluted pumpkin, Klebsiella 33.3%, E. coli 16.7%. From the result, it was concluded that E. coli and Proteus had the highest occurrence of bacterial contamination of spoilt bitter leaf and fluted pumpkin sold in Sokoto metropolis and recommended sensitization proper hygienic measure during post-harvest handling of these vegetables. KEYWORDS: Isolation, Identification, Bacteria, Vegetables, Food Spoilage, Hygiene

scholarly journals Microbial Contamination of Water in Around Dhaka City

1970 ◽  
Vol 43 (2) ◽  
pp. 273-276 ◽  
Author(s):  
Sahana Parveen ◽  
M Shakir Uddin Ahmed ◽  
Tania Nasreen
Keyword(s):  
Water Contamination ◽  
Microbial Contamination ◽  
Pond Water ◽  
Total Coliform ◽  
Faecal Coliform ◽  
Well Water ◽  
Dhaka City ◽  
E Coli ◽  
Household Water ◽  
Water Pond

A total of 109 water samples were collected from around Dhaka city and examined for microbial contamination. Samples were collected in sterilized screw capped glass bottles, transported to the laboratory in cold and processed within 6 hours of their collection. All river water, pond water and household water were found heavily contaminated with coliform, faecal coliform, E. Coli and Salmonella whereas tube well water and bottled water was devoid of faecal coliform, E. Coli and Salmonella. A significant correlation between total number of total coliform and percentage of Salmonella was also investigated. It is suggested that water must be boiled before use. Key Words: Water contamination, Total coliform, Faecal coliform, Salmonella DOI: 10.3329/bjsir.v43i2.972 Bangladesh J. Sci. Ind. Res. 43(2), 273-276, 2008 

scholarly journals Prevalence of Salmonella and Escherichia coli contamination in shrimp (Penaeus monodon) farms, depots and processing plants in different areas of Bangladesh

2016 ◽  
Vol 2 (2) ◽  
pp. 171-176 ◽  
Author(s):  
Md Faridullah ◽  
Vikash Chandra Roy ◽  
Ulfat Jahan Lithi
Keyword(s):  
Escherichia Coli ◽  
Penaeus Monodon ◽  
Conventional Technique ◽  
Indicator Organisms ◽  
Isolation And Identification ◽  
Farm Level ◽  
E Coli ◽  
Processing Plants ◽  
Water Pond ◽  
Seafood Processing

A study was conducted to determine the level of contamination by indicator organisms (Salmonella and Escherichia coli) in shrimp (Penaeus monodon) farms, depots and processing plants of Cox’s Bazar, Khulna, Bagerhat and Satkhira districts of Bangladesh using conventional technique of bacterial isolation and identification. The results of this study revealed that prevalence of Salmonella positive samples was 43.7%, 62.5%, 20% and 0.0% for water, pond scum, shrimp and basket samples, respectively at farm level. Meanwhile, the prevalence of E. coli positive samples was 62.5%, 43.7%, 60% and 60% for water, pond scum, shrimp and basket samples, respectively at farm level. In case of depots, shrimp, basket and mat samples were analyzed and found 20%, 56.3% and 23% positive for Salmonella and 53.3%, 37.5% and 92.3% positive for E. coli. Bacteriological assessment of the shrimp samples obtained from four seafood processing plants revealed that all the samples were found contaminated with Salmonella and E. coli except the samples of one industry. Investigation finally showed that with few exceptions all the samples from farms, depots and processing plants have different levels of contamination by Salmonella and E. coli, which is very much alarming for shrimp industry of Bangladesh.Asian J. Med. Biol. Res. June 2016, 2(2): 171-176

Salmonella and the Sanitary Quality of Aquacultured Shrimp

2005 ◽  
Vol 68 (12) ◽  
pp. 2527-2532 ◽  
Author(s):  
BRETT KOONSE ◽  
WILLIAM BURKHARDT ◽  
STUART CHIRTEL ◽  
GEORGE P. HOSKIN
Keyword(s):  
Fecal Coliform ◽  
Fold Increase ◽  
Pond Water ◽  
Fecal Coliforms ◽  
Coliform Bacteria ◽  
Shrimp Aquaculture ◽  
Fecal Bacteria ◽  
Shrimp Culture ◽  
E Coli ◽  
Unit Increase

In this study, we examined the prevalence of Salmonella and coliform bacteria on shrimp aquaculture farms to develop guidelines or preventative measures for reducing Salmonella and fecal contamination on products harvested from these farms. The U.S. Food and Drug Administration, in conjunction with foreign government regulatory agencies, the aquaculture industry, and academia affiliates, analyzed 1,234 samples from 103 shrimp aquaculture farms representing six countries between July 2001 and June 2003 for fecal coliforms, Escherichia coli, and Salmonella. A significant relationship was found (P = 0.0342) between the log number of fecal bacteria and the probability that any given sample would contain Salmonella. The likelihood of any given sample containing Salmonella was increased by 1.2 times with each 10-fold increase in either fecal coliform or E. coli concentration. The statistical relationship between Salmonella concentration and that of both fecal coliforms and E. coli was highest in grow-out pond water (P = 0.0042 for fecal coliforms and P = 0.0021 for E. coli). The likelihood of finding Salmonella in grow-out pond water increased 2.7 times with each log unit increase in fecal coliform concentration and 3.0 times with each log unit increase in E. coli concentration. Salmonella is not part of the natural flora of the shrimp culture environment nor is it inherently present in shrimp grow-out ponds. The occurrence of Salmonella bacteria in shrimp from aquaculture operations is related to the concentration of fecal bacteria in the source and grow-out pond water.

Ammonia-induced cell envelope injury in Escherichia coli and Enterobacter aerogenes

1990 ◽  
Vol 36 (8) ◽  
pp. 525-529 ◽  
Author(s):  
Gerardo Naundorf ◽  
Nicholas G. Aumen
Keyword(s):  
Escherichia Coli ◽  
Outer Membrane ◽  
Cell Injury ◽  
Cell Envelope ◽  
Enterobacter Aerogenes ◽  
Ammonia Concentration ◽  
E Coli ◽  
Colony Forming Units ◽  
Pure Cultures ◽  
Cell Envelopes

Ammonia-induced cell envelope injury was examined in pure cultures of Escherichia coli and Enterobacter aerogenes. Cell injury, as determined by the ratio of colony-forming units on m-T7 agar to colony-forming units on m-Endo agar, increased with exposure to increasing concentrations of ammonia. Cell envelopes appeared to be the site of injury as indicated by increasing susceptibility to lysozyme with increasing ammonia concentration. Cells exposed to ammonia also exhibited more cellular leakage than control cells. Leakage from cells exposed to ammonia included proteins, and all leaked substances increased in concentration as ammonia concentrations increased. The concentration of 2-keto-3-deoxyoctonate (KDO) in the outer membrane of E. coli increased with ammonia exposure, while KDO concentration in the outer membrane of E. aerogenes decreased. The results suggest that exposure of E. coli cells to high concentrations of ammonia disrupts the outer membrane and lipopolysaccharide-associated proteins, while E. aerogenes cells are affected through the disruption of bonds between KDO and the outer membrane. Key words: injury, coliform, ammonia, cell envelope.

Development and validation of a FISH-based method for the detection and quantification of E. coli and coliform bacteria in water samples

2011 ◽  
Vol 64 (7) ◽  
pp. 1435-1442 ◽  
Author(s):  
Michael Hügler ◽  
Karin Böckle ◽  
Ingrid Eberhagen ◽  
Karin Thelen ◽  
Claudia Beimfohr ◽  
...  
Keyword(s):  
Water Samples ◽  
Fluorescent Dyes ◽  
Direct Detection ◽  
Simultaneous Detection ◽  
Agar Plate ◽  
Coliform Bacteria ◽  
Bacterial Cells ◽  
Indicator Organisms ◽  
E Coli ◽  
Pure Cultures

Monitoring of microbiological contaminants in water supplies requires fast and sensitive methods for the specific detection of indicator organisms or pathogens. We developed a protocol for the simultaneous detection of E. coli and coliform bacteria based on the Fluorescence in situ Hybridization (FISH) technology. This protocol consists of two approaches. The first allows the direct detection of single E. coli and coliform bacterial cells on the filter membranes. The second approach includes incubation of the filter membranes on a nutrient agar plate and subsequent detection of the grown micro-colonies. Both approaches were validated using drinking water samples spiked with pure cultures and naturally contaminated water samples. The effects of heat, chlorine and UV disinfection were also investigated. The micro-colony approach yielded very good results for all samples and conditions tested, and thus can be thoroughly recommended for usage as an alternative method to detect E. coli and coliform bacteria in water samples. However, during this study, some limitations became visible for the single cell approach. The method cannot be applied for water samples which have been disinfected by UV irradiation. In addition, our results indicated that green fluorescent dyes are not suitable to be used with chlorine disinfected samples.

scholarly journals Isolation and serological identification of enteropathogenic Escherichia coli in pasteurized milk in Brazil

2001 ◽  
Vol 35 (4) ◽  
pp. 375-379 ◽  
Author(s):  
Zoraide N da Silva ◽  
Adriana S da Cunha ◽  
Márcia C Lins ◽  
Letícia de AM Carneiro ◽  
Angela C de F Almeida ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Rio De Janeiro ◽  
Coliform Bacteria ◽  
Plate Count ◽  
Enteropathogenic Escherichia Coli ◽  
Isolation And Identification ◽  
Probable Number ◽  
Pasteurized Milk ◽  
E Coli ◽  
Physiological Tests

OBJECTIVE: To evaluate the microbiological quality of pasteurized milk commercialized in Rio de Janeiro, Brazil, and determine serologically enteropathogenic Escherichia coli (EPEC) strains in E. coli isolates obtained from milk samples. METHODS: Ninety samples of pasteurized milk -- types B and C -- of three different commercial brands, purchased in supermarkets and bakeries in Rio de Janeiro, were examined. The amount of total and fecal coliform bacteria was estimated using the Most Probable Number technique. Mesophilic, psychrotrophic, and thermoduric microorganism counts were determined by the Standard Plate Count technique. Isolation and identification of E. coli were carried out using conventional physiological tests. Commercial antisera were used for serological characterization of EPEC. RESULTS: The three milk brands analyzed revealed bacterial counts above the regulated values of the Brazilian government. It was found that among 208 strains of E. coli isolated, 46 (22.1%) were serologically classified as EPEC. The most common EPEC serogroup was O55 (15.2%). CONCLUSIONS: Though recent studies on virulence factors indicate that not all strains serologically classified as EPEC are able to attaching/effacing lesion, it is believed that the isolation of EPEC serogroups from pasteurized milk represent a potential risk for children, as well as an indicative of the presence of other enteropathogens.

NON-LETHAL INJURY AND LIMITATIONS OF RECOVERY OF COLIFORM ORGANISMS ON SELECTIVE MEDIA1

1970 ◽  
Vol 33 (10) ◽  
pp. 445-448 ◽  
Author(s):  
R. B. Maxcy
Keyword(s):  
Cell Injury ◽  
Inhibitory Effect ◽  
Selective Medium ◽  
Coliform Bacteria ◽  
Plate Count ◽  
Limiting Factor ◽  
Freezing And Thawing ◽  
Selective Media ◽  
Standard Plate Count ◽  
Plate Count Agar

Cell injury as a factor in the enumeration of coliform bacteria with selective media was evaluated. Non-lethal injury reduced the ability of cells to produce outgrowth. Escherichia coli and Aerobacter aerogenes were equally sensitive. Brilliant green lactose bile broth, desoxycholate lactose agar, and violet red bile agar were similar in inhibitory effect. Cell injury occurred with sub-lethal heat treatments, exposure to chlorine, exposure to sodium chloride, and freezing and thawing cycles. Circumstances to inflict injury are found in common environmental conditions of the food industry. Presence of injured cells may provide a count with a selective medium that is only 10% of the total count obtained with standard plate count agar. The limiting factor for recovery in selective media was associated with the surfactant. An understanding of these limitations in the use of selective media in quality control and public health applications of the tests should contribute to proper interpretation of results.

scholarly journals Escherichia coli Reduction in Water by Zero-Valent Iron–Sand Filtration Is Based on Water Quality Parameters

Water ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 2702
Author(s):  
Seongyun Kim ◽  
Katherine Eckart ◽  
Sarah Sabet ◽  
Pei C. Chiu ◽  
Amy Rebecca Sapkota ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pond Water ◽  
Deionized Water ◽  
Zero Valent Iron ◽  
Water Type ◽  
Agricultural Water ◽  
Sand Filtration ◽  
Sand Filters ◽  
E Coli ◽  
Influent Water

Improving the microbial quality of agricultural water through filtration can benefit small farms globally. The incorporation of zero-valent iron (ZVI) into sand filters (ZVI–sand) has been effective in reducing E. coli, Listeria spp., and viruses from agricultural water. This study evaluated ZVI–sand filtration in reducing E. coli levels based on influent water type and the percentage of ZVI in sand filters. A ZVI–sand filter (50% ZVI/50% sand) significantly (p < 0.001) reduced E. coli levels in deionized water by more than 1.5 log CFU/mL compared to pond water over six separate trials, indicating that water type impacts E. coli removal. Overall reductions in E. coli in deionized water and pond water were 98.8 ± 1.7% and 63 ± 24.0% (mean ± standard deviation), respectively. Filters constructed from 50% ZVI/50% sand showed slightly more reduction in E. coli in pond water than filters made from a composition of 35% ZVI/65% sand; however, the difference was not statistically significant (p = 0.48). Principal component analysis identified that the turbidity and conductivity of influent water affected E. coli reductions in filtered water in this study. ZVI–sand filtration reduces Escherichia coli levels more effectively in waters that contain low turbidity values.

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