Detection of Escherichia coli by the nutrient agar plus 4-methylumbelliferyl β-D-glucuronide (MUG) membrane filter method

1993 ◽  
Vol 39 (11) ◽  
pp. 1066-1070 ◽  
Author(s):  
Lois C. Shadix ◽  
Michele E. Dunnigan ◽  
Eugene W. Rice
Keyword(s):  
Escherichia Coli ◽  
Membrane Filtration ◽  
Membrane Filter ◽  
Nutrient Agar ◽  
Coliform Bacteria ◽  
Filter Method ◽  
Isolation Medium ◽  
Long Wavelength ◽  
E Coli ◽  
Membrane Filter Method

A two-step membrane filter procedure was evaluated to determine the ability to differentiate Escherichia coli from other coliform bacteria recovered from water. M-Endo LES agar incubated at 35 °C for 24 ± 2 h was used as the initial isolation medium. Membranes containing coliform colonies were transferred to nutrient agar plus 4-methylumbelliferyl β-D-glucuronide (MUG) and incubated for an additional 4 h at 35 °C. Escherichia coli colonies were distinguished by fluorescence when viewed under a long-wavelength ultraviolet light. A total of 119 MUG-positive colonies were isolated from 15 water sources, of which 115 (96.6%) were identified as E. coli. An examination of 182 pure culture environmental E. coli isolates revealed that 167 isolates (91.8%) exhibited fluorescence on the nutrient agar plus MUG medium. Survivors of E. coli cultures exposed to chlorination were also capable of producing a positive MUG reaction.Key words: membrane filtration, 4-methylumbelliferyl β-D-glucuronide (MUG), Escherichia coli, water.

scholarly journals Sampling considerations for herd-level measurement of faecal Escherichia coli antimicrobial resistance in finisher pigs

1999 ◽  
Vol 122 (3) ◽  
pp. 485-496 ◽  
Author(s):  
R. H. DUNLOP ◽  
S. A. McEWEN ◽  
A. H. MEEK ◽  
R. M. FRIENDSHIP ◽  
W. D. BLACK ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Membrane Filter ◽  
Filter Method ◽  
Animal Testing ◽  
E Coli ◽  
Level Measurement ◽  
Faecal Samples ◽  
Membrane Filter Method ◽  
Estimate Prevalence

The objective of this study was to determine the most efficient means of sampling faeces of finisher pigs for accurate and precise farm-level estimates of antimicrobial resistance among faecal Escherichia coli. Resistance to tetracycline and gentamicin of 8250 isolates of E. coli from 55 finisher pigs on one farm was measured with a hydrophobic grid membrane filter method. The between-pig, within-pen component of variance in resistance was large (97·5%), while between-pen, within-room and between-room components were small (2·5% and 0%, respectively). Using these resistance data, the abilities of two sampling strategies to estimate prevalence were modelled with a Monte Carlo ‘bootstrap’ procedure. Compositing faecal samples from several pigs before testing produced unbiased and precise estimates of prevalence and is simpler technically than individual animal testing.

Enumeration of Total Coliforms, Fecal Coliforms, and Escherichia coli in Foods by Hydrophobic Grid Membrane Filter: Collaborative Study

1984 ◽  
Vol 67 (4) ◽  
pp. 812-823
Author(s):  
Phyllis Entis ◽  
◽  
B Bennett ◽  
M H Brodsky ◽  
D M Burgener ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Membrane Filter ◽  
Collaborative Study ◽  
Reference Method ◽  
Black Pepper ◽  
Fecal Coliforms ◽  
Filter Method ◽  
Total Coliforms ◽  
E Coli ◽  
Membrane Filter Method

Abstract A collaborative study was conducted in 18 laboratories to assess the performance of the hydrophobic grid membrane filter method against that of the AOAC official first action method 46.013-46.016 for enumerating total and fecal coliforms and Escherichia coli. The study was carried out on frozen breaded fish, raw comminuted poultry, unroasted walnut pieces, ground black pepper, and cheddar cheese. The hydrophobic grid membrane filter method recovered significantly larger numbers of target bacteria in 7 of the food/analysis combinations: fecal coliforms in fish; E. coli in poultry; fecal coliforms and E. coli in walnuts; and total coliforms, fecal coliforms and E. coli in black pepper. Random error (Sr2) associated with the hydrophobic grid membrane filter method was significantly lower than that of the reference method in over 30% of the paired sample series. The hydrophobic grid membrane filter method for total coliform, fecal coliform, and E. coli enumeration in foods has been adopted official first action.

Membrane Filter Method Based on FC-5-Bromo-4-Chloro-3-lndolyl-β-d-Glucuronide Medium Facilitates Enumeration of Escherichia coli in Foods and Poultry Carcass Rinses

1998 ◽  
Vol 61 (3) ◽  
pp. 360-364 ◽  
Author(s):  
A. N. SHARPE ◽  
L. J. PARRINGTON
Keyword(s):  
Escherichia Coli ◽  
Membrane Filter ◽  
Most Probable Number ◽  
Filter Method ◽  
Simple Method ◽  
Probable Number ◽  
E Coli ◽  
Membrane Filter Method ◽  
Alfalfa Sprouts ◽  
Bean Sprouts

Three enumeration methods for Escherichia coli in foods, the Health Protection Branch most-probable-number (MPN) method MFHPB-19, a hydrophobic grid membrane filter method MFHPB-26 (HGMF-indole), and a hydrophobic grid membrane filter method utilizing 5-bromo-4-chloro-3-indolyl-β-d-glucuronide in a (modified) mFC agar (HGMF-FC-BCIG) were compared in 80 food samples that included naturally and artificially contaminated raw vegetables, mung bean and alfalfa sprouts, raw meats, and chicken carcass rinses. The number of samples confirmed as positive for E. coli were 44, 36, and 42 for the MPN, HGMF-indole, and HGMF-FC-BCIG methods, respectively. By the MPN method, E. coli was detected in 3 samples at levels below the limits of detection of the HGMFs; but the MPN method was very time-consuming. With the HGMF-indole procedure E. coli was missed in 4 artificially contaminated samples. With the HGMF-FC-BCIG method E. coli was enumerated in 1 sample of bean sprouts missed by both the MPN and HGMF-indole procedures. High levels of indole-positive Klebsiella spp. in bean sprouts interfered with the HGMF-indole method, but the blue colonies of E. coli were easily observed in the HGMF-FC-BCIG method. Specificity of the HGMF-FC-BCIG method is high enough that routine confirmation should be unnecessary; however, confirmation of presumptive E. coli is easier since no lethal indole-staining step is involved. It appears to be a very simple method for quantifying E. coli in foods or carcass rinses.

Acceptability of Individual Water Supplies as Judged by a Single Test for Total Coliform Bacteria

1980 ◽  
Vol 43 (7) ◽  
pp. 563-563
Author(s):  
E. P. MERRILL
Keyword(s):  
Membrane Filter ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
Most Probable Number ◽  
Filter Method ◽  
Single Test ◽  
Water Supplies ◽  
Probable Number ◽  
Dug Wells ◽  
Membrane Filter Method

Of 658 individual water supplies tested over an 8-year period, 69% of drilled wells, 62% of driven wells, 27% of dug wells and 32% of springs were judged acceptable on the basis of a single test for total coliforms. The acceptability standard consisted of 0 to 1 coliforms/100 ml of sample by the membrane filter method or a Most Probable Number index of less than 2.2 (presumptive and confirmed tests).

Enumeration of β-Glucuronidase-Positive Escherichia coli in Foods by Using the ISO-GRID Method with SD-39 Agar

1998 ◽  
Vol 61 (7) ◽  
pp. 913-916 ◽  
Author(s):  
PHYLLIS ENTIS ◽  
IRINA LERNER
Keyword(s):  
Escherichia Coli ◽  
Membrane Filter ◽  
Reference Method ◽  
Grid Method ◽  
Test Method ◽  
Cottage Cheese ◽  
Filter Method ◽  
Official Method ◽  
Membrane Filter Method ◽  
Aoac Official

A study was undertaken to compare β-glucuronidase-positive Escherichia coli counts produced by the ISO-GRID hydrophobic grid membrane filter method using SD-39 agar (test method) with those produced by AOAC Official Method 990.11, an existing ISO-GRID method using lactose monensin glucuronate agar and buffered MUG agar (reference method). The methods were evaluated using 21 food products, with three independent lots of five replicate samples analyzed per product by both methods. The test and reference methods were statistically equivalent for 19 of the 21 products; frozen, raw ground lamb produced significantly higher counts using the reference method, whereas counts obtained from cottage cheese were significantly higher using the SD-39 agar-based method.

scholarly journals Membrane filter method for enumerating Escherichia coli.

1981 ◽  
Vol 41 (5) ◽  
pp. 1152-1158 ◽  
Author(s):  
A P Dufour ◽  
E R Strickland ◽  
V J Cabelli
Keyword(s):  
Escherichia Coli ◽  
Membrane Filter ◽  
Filter Method ◽  
Membrane Filter Method

Enumeration of Total Coliforms, Fecal Coliforms, and Escherichia coli in Foods by Hydrophobic Grid Membrane Filter: Supplementary Report

1984 ◽  
Vol 67 (4) ◽  
pp. 811-812
Author(s):  
Phyllis Entis
Keyword(s):  
Escherichia Coli ◽  
Membrane Filter ◽  
Total Coliform ◽  
Fecal Coliforms ◽  
Poultry Meat ◽  
Filter Method ◽  
Total Coliforms ◽  
The Media ◽  
Aoac Method ◽  
Membrane Filter Method

Abstract Raw, comminuted poultry meat was used to determine the specificity of the media and incubation conditions used in the hydrophobic grid membrane filter method. Confirmation rates for target colonies were 100% for total coliforms, 98% for fecal coliforms, and 97-99% for Escherichia coli. The results of total coliform enumeration in 30 pasteurized milk samples by both the hydrophobic grid membrane filter method and AOAC method 46.013-46.016 are also reported.

Sign in / Sign up

Export Citation Format

Share Document