Rapid detection of emetic toxin producing Bacillus cereus strains using triple-primer polymerase chain reaction (PCR) assay

Abstract

Emetic toxin producing Bacillus cereus can cause emetic food poisoning. In this study, an improved triple-primer polymerase chain reaction (PCR) assay was developed as a reliable and rapid identification method for the detection of emetic toxin producing B. cereus strains based on the unique gene sequences of the CER, ces and groEL. Specificity and sensitivity of the primers was confirmed using conventional PCR and gel electrophoresis. In addition, detection limit was determined in pure culture, rice and milk. In brief, sensitivity in pure culture was 10 fold or more higher than artificially inoculated food samples in improved triple-primer PCR detection limit assay. The primers did not react with genes from enterotoxin producing B. cereus or other non-target strains. The presented PCR assay is a useful tool for the rapid screening and diagnosis of emetic toxin producing B. cereus strains in food.   Key words: Triple-primer polymerase chain reaction (PCR), Bacillus cereus, emetic toxin, food poisoning.