Quantitative Detection of E.coli O157:H7 in Ground Beef

Escherichia coli O157:H7 is recognized as a major human enteropathogen. A direct spectrophotometric immune agglutination - the first assay had ever published - was developed for quantitation of specific Escherichia coli O157 IgG. A new cell lysis solution designated TZ was also developed and found superior to a variety of cell lysing methods prior to PCR. A 6-fold increase of extracted E. coli 0157:H7 cells from seeded in ground beef was achieved via developing a differential extraction procedure. Highest amplification of E. coli O157: H7 was achieved with the aid of TZ lysis solution, extraction procedures and the optimization of PCR procedure; resulted in the detection of 100 cells of SLT-1 and 50 cells with SLT-2 per 10 grams of ground beef.