Rapid protocol (5.25 H) for the detection of Escherichia coli O157 : H7 in raw ground beef by an immuno-capture system (Pathatrix) in combination with Colortrix and CT-SMAC

摘要

A same day protocol for the detection of Escherichia coli O157:H7 by Pathatrix (a novel immuno-capture method) and Colortrix (a rapid ELISA test) was developed. This study indicated that Pathatrix system, which circulated the pre-enriched (4.5 h) samples over paramagnet beads with antibodies (0.5 h), increased the concentration of E. coli 0157:H7 by 1.2-2.6 log CFU/25 g in 0.5 h from enrichment broth (modified EC broth with novobiocin or buffered peptone water). Colortrix, a rapid ELISA system, was used to detect the pathogens in another 0.25 h. Excellent correlation (100%) between positive Pathatrix/Colortrix (5.25 h system) results and positive Pathatrix/plating method with cefixime tellurite sorbitol-MacConkey agar, with initial concentration of 0.7 to 2.1 log CFU/25 g was obtained. This new protocol offers a significant benefit to the meat industry allowing compliance with a "test" and "hold" program for E. coli 0157: H7 in ground beef.