Testing of a Chemiluminescence Enzyme Immunoassay for selective detection of E. Coli O157 from ground beef samples.
The aim of this study was to evaluate a Chemiluminescence Enzyme Immunoassay (CLIA) developed for the detection of E. coli O157:H7, using different E. coli O157 serotypes. The sensitivity and specificity of the kit were determined from the tenfold dilutions of the 24-hour broth cultures of the test strains. According to the results obtained in this trial, the sensitivity of the kit is 10(3)-10(4) cells ml-1, and it is specific for E. coli O157. Twenty-five g ground raw beef samples were prepared and inoculated with E. coli O157:H7 at different CFU g-1. The samples were incubated in 225 ml of modified E. coli broth with novobiocin (mEC + n) at 42 degrees C for 4 h and the immunoassays were performed following the instructions of the manufacturer. According to the results obtained by the CLIA test 10(1)-10(2) E. coli O157 g-1 can be detected from the sample. So this kit seems to be suitable for screening the samples before selective cultivation of E. coli O157:H7.
Kovács
H D
HD
National Food Investigation Institute, H-1465 Budapest 94, P.O. Box 1740, Hungary. oai@oai.hu
Rásky
K
K
D000818:Animals; D002417:Cattle; D019453:Escherichia coli O157 / Q000145:classification / Q000201:enzymology / Q000302:isolation & purification*; D005511:Food Handling; D005516:Food Microbiology / Q000592:standards; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods / Q000592:standards*; D008163:Luminescent Measurements; D008460:Meat / Q000382:microbiology*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity