title: Dead-end ultrafiltration concentration and IMS/ATP-bioluminescence detection of Escherichia coli O157:H7 in recreational water and produce wash.
abstract: The purpose of this study was to develop a detection method for viable E. coli O157:H7 in fresh produce and recreational water. The method was evaluated using eight samples of produce wash and recreational water with or without spiked E. coli O157:H7 at ≤10(2) CFU·ml(-1) and concentrated using dead-end ultrafiltration (DEUF) to produce primary and secondary retentates. Fifty-four matrix replicates of undiluted secondary retentates or dilutions (1:2 or 1:10 in buffer) were evaluated using an IMS/ATP bioluminescence assay (IMS/ATP). Combining primary and secondary DEUF yielded a 2-4 log(10) increase in E. coli O157:H7 concentrations in spiked samples and resulted in signal-to-noise ratios 2-219 fold higher than controls, depending on the sample type. DEUF increased the concentration of E. coli O157:H7 to within the detectable limits of IMS/ATP. The combined assay provided detection of viable E. coli O157:H7 in produce and recreational water. Accurate detection of microbial pathogens using DEUF and IMS/ATP could reduce disease outbreaks from contaminated water sources and food products.
authors: Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620-7115, United States.
authors: Dawn M
authors: DM
authors: Hunter
authors: Stephaney D
authors: SD
authors: Leskinen
authors: Sonia
authors: S
authors: Magaña
authors: Sarah M
authors: SM
authors: Schlemmer
authors: Daniel V
authors: DV
authors: Lim
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis*; D001431:Bacteriological Techniques / Q000379:methods*; D019453:Escherichia coli O157 / Q000737:chemistry / Q000302:isolation & purification*; D018189:Immunomagnetic Separation / Q000379:methods*; D008163:Luminescent Measurements; D050296:Microbial Viability; D014462:Ultrafiltration / Q000379:methods*; D014871:Water Microbiology
chemical_list: D000255:Adenosine Triphosphate