Most probable number methodology for quantifying dilute concentrations and fluxes of Escherichia coli O157:H7 in surface waters

Aims:  To better understand the transport and enumeration of dilute densities of Escherichia coli O157:H7 in agricultural watersheds, we developed a culture‐based, five tube‐multiple dilution most probable number (MPN) method. Methods and Results:  The MPN method combined a filtration technique for...

Full description

Saved in:
Bibliographic Details
Published in:Journal of applied microbiology 2009-02, Vol.106 (2), p.572-579
Main Authors: Jenkins, M.B., Endale, D.M., Fisher, D.S., Gay, P.A.
Format: Article
Language:English
Subjects:
Animals
Bacteriological Techniques - methods
baseflow
Biological and medical sciences
Cattle
Colony Count, Microbial - methods
Environmental Monitoring - methods
Escherichia coli
Escherichia coli O157 - isolation & purification
faecal enterococci
Feces - microbiology
Filtration
Fresh Water - microbiology
Fundamental and applied biological sciences. Psychology
mass flux
Microbiology
Water - analysis
Water Microbiology
Water Movements
watershed
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Aims:  To better understand the transport and enumeration of dilute densities of Escherichia coli O157:H7 in agricultural watersheds, we developed a culture‐based, five tube‐multiple dilution most probable number (MPN) method. Methods and Results:  The MPN method combined a filtration technique for large volumes of surface water with standard selective media, biochemical and immunological tests, and a TaqMan confirmation step. This method determined E. coli O157:H7 concentrations as low as 0·1 MPN per litre, with a 95% confidence level of 0·01–0·7 MPN per litre. Escherichia coli O157:H7 densities ranged from not detectable to 9 MPN per litre for pond inflow, from not detectable to 0·9 MPN per litre for pond outflow and from not detectable to 8·3 MPN per litre for within pond. The MPN methodology was extended to mass flux determinations. Fluxes of E. coli O157:H7 ranged from 104 MPN per hour. Conclusion:  This culture‐based method can detect small numbers of viable/culturable E. coli O157:H7 in surface waters of watersheds containing animal agriculture and wildlife. Significance and Impact of the Study:  This MPN method will improve our understanding of the transport and fate of E. coli O157:H7 in agricultural watersheds, and can be the basis of collections of environmental E. coli O157:H7.
ISSN:1364-5072
1365-2672
DOI:10.1111/j.1365-2672.2008.04028.x