Presence and Correlation of Some Enteric Indicator Bacteria, Diarrheagenic Escherichia coli Pathotypes, and Salmonella Serotypes in Alfalfa Sprouts from Local Retail Markets in Pachuca, Mexico

2015 ◽  
Vol 78 (3) ◽  
pp. 609-614 ◽  
Author(s):  
ESMERALDA RANGEL-VARGAS ◽  
CARLOS A. GÓMEZ-ALDAPA ◽  
M. del REFUGIO TORRES-VITELA ◽  
ANGÉLICA VILLARRUEL-LÓPEZ ◽  
ALBERTO J. GORDILLO-MARTÍNEZ ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Salmonella Enterica ◽  
Indicator Bacteria ◽  
Coliform Bacteria ◽  
Probable Number ◽  
Retail Markets ◽  
First Report ◽  
E Coli ◽  
Diarrheagenic Escherichia Coli ◽  
Alfalfa Sprouts

Data on the presence of diarrheagenic Escherichia coli pathotypes (DEPs) in alfalfa sprouts and correlations between the presence of coliform bacteria (CB), fecal coliforms (FC), E. coli, DEPs, and Salmonella in alfalfa sprouts are not available. The presence of and correlations between CB, FC, E. coli, DEPs, and Salmonella in alfalfa sprouts were determined. One hundred sprout samples were collected from retail markets in Pachuca, Hidalgo State, Mexico. The presence of indicator bacteria and Salmonella was determined using conventional culture procedures. DEPs were identified using two multiplex PCR procedures. One hundred percent of samples were positive for CB, 90% for FC, 84% for E. coli, 10% for DEPs, and 4% for Salmonella. The populations of CB ranged from 6.2 up to 8.6 log CFU/g. The FC and E. coli concentrations were between <3 and 1,100 most probable number (MPN)/g. The DEPs identified included enterotoxigenic E. coli (ETEC; 2%), enteropathogenic E. coli (EPEC; 3%), and Shiga toxin–producing E. coli (STEC; 5%). No E. coli O157:H7 strains were detected in any STEC-positive samples. In samples positive for DEPs, the concentrations ranged from 210 to 240 MPN/g for ETEC, 28 to 1,100 MPN/g for EPEC, and 3.6 to 460 MPN/g for STEC. The Salmonella isolates identified included Salmonella enterica serotype Typhimurium in three samples and Salmonella enterica serotype Enteritidis in one. STEC and Salmonella Typhimurium were identified together in one sample. Positive correlations were observed between FC and E. coli, between FC and DEPs, and between E. coli and DEPs. Negative correlations occurred between CB and DEPs and between CB and Salmonella. Neither FC nor E. coli correlated with Salmonella in the sprout samples. To our knowledge, this is the first report of ETEC, EPEC, and STEC isolated from alfalfa sprouts and the first report of correlations between different indicator groups versus DEPs and Salmonella.

scholarly journals Escherichia coli O157:H7 in Drin Prevalence of Escherichia coli O157:H7 in Drink from Different Food Premises in Kota Samarahan Sarawak

2019 ◽  
Vol 2 (2) ◽  
pp. a13-19
Author(s):  
ELEXSON NILLIAN ◽  
AMIZA NUR ◽  
DIYANA NUR ◽  
AMIRAH ZAKIRAH ◽  
GRACE BEBEY
Keyword(s):  
Escherichia Coli ◽  
Drinking Water ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Plain Water ◽  
Escherichia Coli O157 ◽  
Probable Number ◽  
E Coli ◽  
Preventive Actions ◽  
Stx1 Gene

Contamination of drinks with E. coli O157:H7 served in food premises such as restaurants can cause haemorrhagic colitis and haemolytic uremic syndrome to humans. The presence or absence of faecal pathogen was demonstrated using coliform group as indicator microorganisms. Therefore, this study was conducted to detect the presence of E. coli O157:H7 in drinking water from food restaurant premise in Kota Samarahan and Kuching to ensure safe and potable drinking water is served to the consumer. A total of thirty (n=30) drink samples including six types of each of the samples are cold plain water, iced tea, iced milo, syrup and iced milk tea. Most Probable Number (MPN) procedure was used in this study to enumerate the MPN values of coliform bacteria in each drink collected. A total of 53.33% (16/30) of the drink samples showed positive E. coli detection. Then, the PCR assay showed 6.25% (one out of 16 isolates) samples were positive and carried stx1 gene produced by E. coli O157:H7 in iced milo sample types. This study showed the drinks collected from food premises was contaminated with faecal contamination, which was not safe to drink by the consumer. Therefore, preventive actions should be taken to prevent foodborne illness outbreak in future

scholarly journals Comparison of the Compact Dry EC with the Most Probable Number Method (AOAC Official Method 966.24) for Enumeration of Escherichia coli and Coliform Bacteria in Raw Meats: Performance-Tested MethodSM 110402

2006 ◽  
Vol 89 (1) ◽  
pp. 100-114 ◽  
Author(s):  
Hidemasa Kodaka ◽  
Shingo Mizuochi ◽  
Hajime Teramura ◽  
Tadanobu Nirazuka ◽  
David Goins ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Water Soluble ◽  
Test Method ◽  
Gelling Agent ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Official Method ◽  
Probable Number ◽  
E Coli ◽  
Raw Meats

Abstract Compact Dry E. coli/Coliform Count (EC) is a ready-to-use test method for the enumeration of Escherichia coli and coliform bacteria in food. The plates are presterilized and contain culture medium and a cold water-soluble gelling agent. The medium should be rehydrated with 1 mL diluted sample inoculated onto the center of the self-diffusible medium, allowing the solution to diffuse by capillary action. The plate can be incubated at 35C for 2024 h and the colonies counted without any further working steps. The Compact Dry EC medium plates were validated as an analysis tool for determining colony-forming units (CFU) of E. coli and coliform bacteria from a variety of raw meats using 5 different types of raw meats. The performance tests were conducted at 35C. In all studies performed, no apparent differences were observed between the Compact Dry ECmethod and theAOAC Official Method 966.24 results. For the accuracy claim (n = 75), a correlation factor of r2 = 0.93 (E. coli) and r2 = 0.93 (coliform bacteria) could be assigned, as stated in the application for Performance-Tested MethodSM.

scholarly journals Differences in Growth of Salmonella enterica and Escherichia coli O157:H7 on Alfalfa Sprouts

2002 ◽  
Vol 68 (6) ◽  
pp. 3114-3120 ◽  
Author(s):  
A. O. Charkowski ◽  
J. D. Barak ◽  
C. Z. Sarreal ◽  
R. E. Mandrell
Keyword(s):  
Escherichia Coli ◽  
Irrigation Water ◽  
Salmonella Enterica ◽  
Fluorescent Protein ◽  
Human Pathogens ◽  
E Coli ◽  
Inoculum Dose ◽  
Alfalfa Sprouts ◽  
Green Fluorescent ◽  
Alfalfa Seeds

ABSTRACT Sprout producers have recently been faced with several Salmonella enterica and Escherichia coli O157:H7 outbreaks. Many of the outbreaks have been traced to sprout seeds contaminated with low levels of human pathogens. Alfalfa seeds were inoculated with S. enterica and E. coli O157:H7 strains isolated from alfalfa seeds or other environmental sources and sprouted to examine growth of these human pathogens in association with sprouting seeds. S. enterica strains grew an average of 3.7 log10 on sprouting seeds over 2 days, while E. coli O157:H7 strains grew significantly less, an average of 2.3 log10. The initial S. enterica or E. coli O157:H7 inoculum dose and seed-sprouting temperature significantly affected the levels of both S. enterica and E. coli O157:H7 on the sprouts and in the irrigation water, while the frequency of irrigation water replacement affected only the levels of E. coli O157:H7. Colonization of sprouting alfalfa seeds by S. enterica serovar Newport and E. coli O157:H7 strains transformed with a plasmid encoding the green fluorescent protein was examined with fluorescence microscopy. Salmonella serovar Newport colonized both seed coats and sprout roots as aggregates, while E. coli O157:H7 colonized only sprout roots.

Comparison of the SimPlate Coliform and Escherichia coli Test with Petrifilm, Three-Tube MPN, and VRBA + MUG Methods for Enumerating Coliforms and E. coli in Food

1998 ◽  
Vol 61 (4) ◽  
pp. 444-449 ◽  
Author(s):  
D. E. TOWNSEND ◽  
R. L. IRVING ◽  
A. NAQUI
Keyword(s):  
Escherichia Coli ◽  
Correlation Coefficients ◽  
Raw Milk ◽  
Food Samples ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Additional Food ◽  
Suitable Alternative ◽  
Probable Number ◽  
E Coli

SimPlate for coliforms and Escherichia coli (CEc) is a new method for the detection and quantification of coliforms and E. coli in food. Internal validation of the method was carried out at IDEXX Laboratories (Westbrook, ME) with 180 food samples representing a variety of different food matrices and compared against three-tube MPN (most probable number), VRBA (violet red bile agar) + MUG, and Petrifilm (E. coli count) methods. SimPlate CEc was highly correlated with each of these methods for the quantification of coliform bacteria (r ≥ 0.90). An insignificant number of food samples were found to contain E. coli; therefore, no meaningful correlation data could be generated. Four hundred forty-four additional food samples were tested at five collaborating laboratories for the presence of coliforms and E. coli using SimPlate CEc and either VRBA + MUG or Petrifilm (E. coli count). Regression analysis of data from SimPlate for CEc versus Petrifilm E. coli count plates generated correlation coefficients (r) of at least 0.89 for total coliforms and at least 0.90 for generic E. coli. Correlation coefficients between SimPlate for CEc and VRBA + MUG data were at least 0.90 for coliforms and at least 0.86 for E. coli. SimPlate for CEc demonstrated better recovery of E. coli than Petrifilm when high populations of bacteria were present. E. coli was not detected in 20 of 50 (40%) raw milk samples tested by the Petrifilm method due to the presence of interfering coliform and noncoliform bacteria. It is concluded that SimPlate for CEc is a suitable alternative for determining numbers of coliform bacteria and E. coli in food.

scholarly journals First Report of Plasmid-Mediated Quinolone Resistance Determinant qnrS1 in an Escherichia coli Strain of Animal Origin in Italy

2009 ◽  
Vol 53 (7) ◽  
pp. 3112-3114 ◽  
Author(s):  
Marina Cerquetti ◽  
Aurora García-Fernández ◽  
Maria Giufrè ◽  
Daniela Fortini ◽  
Marisa Accogli ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Salmonella Enterica ◽  
Coli Strain ◽  
Quinolone Resistance ◽  
Resistance Determinant ◽  
Animal Origin ◽  
Animal Reservoir ◽  
First Report ◽  
E Coli ◽  
Positive Strain

ABSTRACT A qnrS1-positive strain of Escherichia coli was detected among 73 poultry isolates showing ciprofloxacin MICs of ≥0.125 μg/ml. The qnrS1 gene was associated with a Tn3-like transposon, as previously described to occur in a Salmonella enterica serovar Infantis strain of animal origin, but the plasmid scaffold carrying this element resembled that of a plasmid previously identified in Salmonella enterica serovar Dublin. These elements suggest genetic exchanges among Salmonella and E. coli and a potential animal reservoir for the qnr genes.

Incidence and Behavior of Salmonella and Escherichia coli on Whole and Sliced Zucchini Squash (Cucurbita pepo) Fruit

2010 ◽  
Vol 73 (8) ◽  
pp. 1423-1429 ◽  
Author(s):  
JAVIER CASTRO-ROSAS ◽  
EVA MARÍA SANTOS LÓPEZ ◽  
CARLOS ALBERTO GÓMEZ-ALDAPA ◽  
CESAR ABELARDO GONZÁLEZ RAMÍREZ ◽  
JOSÉ ROBERTO VILLAGOMEZ-IBARRA ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Inoculum Level ◽  
Probable Number ◽  
Initial Inoculum ◽  
E Coli ◽  
Thermotolerant Coliforms ◽  
Salmonella Serotypes ◽  
And Behavior

The incidence of coliform bacteria (CB), thermotolerant coliforms (TC), Escherichia coli, and Salmonella was determined for zucchini squash fruit. In addition, the behavior of four serotypes of Salmonella and a cocktail of three E. coli strains on whole and sliced zucchini squash at 25 ± 2°C and 3 to 5°C was tested. Squash fruit was collected in the markets of Pachuca city, Hidalgo State, Mexico. CB, TC, E. coli, and Salmonella were detected in 100, 70, 62, and 10% of the produce, respectively. The concentration ranged from 3.8 to 7.4 log CFU per sample for CB, and <3 to 1,100 most probable number per sample for TC and E. coli. On whole fruit stored at 25 ± 2°C or 3 to 5°C, no growth was observed for any of the tested microorganisms or cocktails thereof. After 15 days at 25 ± 2°C, the tested Salmonella serotypes had decreased from an initial inoculum level of 7 log CFU to <1 log, and at 3 to 5°C they decreased to approximately 2 log. Survival of E. coli was significantly greater than for the Salmonella strains at the same times and temperatures; after 15 days, at 25 ± 2°C E. coli cocktail strains had decreased to 3.4 log CFU per fruit and at 3 to 5°C they decreased to 3.6 log CFU per fruit. Both the Salmonella serotypes and E. coli strains grew when inoculated onto sliced squash: after 24 h at 25 ± 2°C, both bacteria had grown to approximately 6.5 log CFU per slice. At 3 to 5°C, the bacterial growth was inhibited. The squash may be an important factor contributing to the endemicity of Salmonella in Mexico.

ColiComplete® Substrate-Supporting Disc Method for Confirmed Detection of Total Coliforms and Escherichia coli in All Foods: Comparative Study

1994 ◽  
Vol 77 (1) ◽  
pp. 58-63 ◽  
Author(s):  
Philip T Feldsine ◽  
Maria T Falbo-Nelson ◽  
David L Hustead
Keyword(s):  
Escherichia Coli ◽  
Comparative Study ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Probable Number ◽  
Total Coliforms ◽  
E Coli ◽  
Total Coliform Bacteria ◽  
Better Than

Abstract The ColiComplete® substrate-supporting disc (SSD) method for simultaneous confirmed total coliform count and Escherichia coli determination in all foods was compared with the AOAC most probable number (MPN) methods 966.23 and 966.24. In this comparative study, 20 water and food types were analyzed; 7 of these foods were naturally contaminated with coliform bacteria, 6 food types were naturally contaminated with E. coli, and the remaining foods were inoculated with coliform bacteria and/or E. coli. Data were analyzed separately for total coliform bacteria and for E. coli. Mean log MPN counts were determined by the SSD method and the appropriate AOAC MPN procedure. Results were then analyzed for mean log MPN differences and variance, according to methods described by AOAC INTERNATIONAL Results for both total conforms and E. coli indicate that the SSD method is equivalent to or better than AOAC MPN methods 966.23 and 966.24.

scholarly journals Comparison of Colilert-18 with miniaturised most probable number method for monitoring of Escherichia coli in bathing water

2015 ◽  
Vol 14 (1) ◽  
pp. 121-131 ◽  
Author(s):  
Ananda Tiwari ◽  
Seppo I. Niemelä ◽  
Asko Vepsäläinen ◽  
Jarkko Rapala ◽  
Seija Kalso ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
False Negative ◽  
Reference Method ◽  
Water Quality Monitoring ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Probable Number ◽  
E Coli ◽  
Negative Results ◽  
Bathing Water

The purpose of this equivalence study was to compare an alternative method, Colilert-18 Quanti-Tray (ISO 9308-2) with the European bathing water directive (2006/7/EC) reference method, the miniaturised most probable number (MMPN) method (ISO 9308-3), for the analysis of Escherichia coli. Six laboratories analysed a total of 263 bathing water samples in Finland. The comparison was carried out according to ISO 17994:2004. The recovery of E. coli using the Colilert-18 method was 7.0% and 8.6% lower than that of the MMPN method after 48 hours and 72 hours of incubation, respectively. The confirmation rate of presumptive E. coli-positive wells in the Colilert-18 and MMPN methods was high (97.8% and 98.0%, respectively). However, the testing of presumptive E. coli-negative but coliform bacteria-positive (yellow but not fluorescent) Colilert-18 wells revealed 7.3% false negative results. There were more false negatives in the naturally contaminated waters than in the samples spiked with waste water. The difference between the recovery of Colilert-18 and the MMPN method was considered not significant, and subsequently the methods are considered as equivalent for bathing water quality monitoring in Finland. Future bathing water method equivalence verification studies may use the data reported herein. The laboratories should make sure that any wells showing even minor fluorescence will be determined as positive for E. coli.

scholarly journals DETEKSI BAKTERI Escherichia coli DALAM AIR MINUM ISI ULANG YANG DISTERILISASI ULTRAVIOLET DI WILAYAH KECAMATAN JAGAKARSA

Jurnal BIOMA ◽  
2017 ◽  
Vol 11 (1) ◽  
pp. 73
Author(s):  
Rezki Rachmawati ◽  
Muzajjanah Muzajjanah ◽  
Yoswita Rustam
Keyword(s):  
Escherichia Coli ◽  
Drinking Water ◽  
Water Samples ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Coliform Bacterium ◽  
Probable Number ◽  
E Coli ◽  
Biological Contamination ◽  
Drinking Water Samples

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.

Escherichia coli O157 in Ground Beef from Local Retail Markets in Pachuca, Mexico

2013 ◽  
Vol 76 (4) ◽  
pp. 680-684 ◽  
Author(s):  
CARLOS A. GÓMEZ-ALDAPA ◽  
CLAUDIO A. DÍZ-CRUZ ◽  
JORGE F. CERNA-CORTES ◽  
M. del REFUGIO TORRES-VITELA ◽  
ANGELICA VILLARRUEL-LÓPEZ ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pathogenic Bacteria ◽  
Ground Beef ◽  
Culture Method ◽  
Escherichia Coli O157 ◽  
Simultaneous Application ◽  
Retail Markets ◽  
First Report ◽  
E Coli ◽  
Commercial Kits

Escherichia coli O157 strains have been recognized as pathogenic bacteria, of which raw beef is a known vehicle. An evaluation was done of the presence of E. coli O157 in ground beef from local retail markets in Pachuca, Hidalgo State, Mexico. A total of 120 ground beef samples (500 g) were tested for E. coli O157 by simultaneous application of the U.S. Department of Agriculture, Food Safety and Inspection Service (FSIS)'s Microbiology Laboratory Guidebook culture procedure 5.05, and two commercial kits, Reveal for E. coli O157:H7 and Visual Immunoprecipitate Assay (VIP) Gold for enterohemorrhagic E. coli. Two incubation times (8 and 20 h) were used with the commercial kits. Presence of stx1, stx2, and eaeA loci was determined by multiplex PCR. Of 360 subsamples (120 per procedure), 12 samples were found to be E. coli O157 positive by the FSIS culture method. With VIP, 73 subsamples were presumptive positive after 8 h of enrichment, and 60 were presumptive positive after 20 h of enrichment. Of these, only 6 (8 h) and 8 (20 h) subsamples were confirmed true positives with the FSIS method. With Reveal, 60 subsamples were presumptive positive after 8 h of enrichment and 50 were presumptive positive after 20 h of enrichment. Of these, only 6 (8 h) and 8 (20 h) subsamples were confirmed as true positives with the FSIS method. A total of 57 E. coli O157:H7 and 21 E. coli O157 strains were isolated. None of the O157 or O157:H7 strains had stx1 or stx2 loci, and only one had the eaeA locus. To our knowledge, this is the first report of the presence of E. coli O157 in commercial ground beef from Mexico, and the first report of isolation of a large number of stx-negative E. coli O157 and E. coli O157:H7 strains in Mexico.

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