Recirculating immunomagnetic separation and optimal enrichment conditions for enhanced detection and recovery of low levels of Escherichia coli O157:H7 from fresh leafy produce and surface water.

The objective of this study was to develop a rapid, simple method for enhanced detection and isolation of low levels of Escherichia coli O157:H7 from leafy produce and surface water using recirculating immunomagnetic separation (RIMS) coupled with real-time PCR and a standard culture method. The optimal enrichment conditions for the method also were determined. Analysis of real-time PCR data (C(T) values) suggested that incubation of lettuce and spinach leaves rather than rinsates provides better enrichment of E.