Direct Detection of Bacillus cereus and its Enterotoxigenic Genes in Meat and Meat Products by Polymerase Chain Reaction

Abstract

This study was conducted to standardize a method to directly detect B. cereus (gyrB) and its enterotoxigenic genes (hblDAC, nheABC, cytK and entFM) from the meat and meat products by PCR, without going for isolation and identification procedures. The method employed was compared with the standard microbiological procedures to determine its efficacy. Among the 150 food samples (raw meats and meat products) analyzed, 60 (40%) were positive for isolation and 59 (39.33%) turned out positive by direct PCR (targeting sequence within gyrB gene). Food samples screened directly by multiplex-PCR showed almost similar enterotoxin gene profile as of isolates from these samples. Among the positive samples, only two samples from the meat products showed different enterotxigenic gene pattern compared to isolates from these samples. The incidences of various enteroxigenic genes hblD, hblA, hblC, nheA, nheB, nheC, cytK and entFM was 66.10%, 66.10%, 67.78%, 96.61%, 96.61%, 93.22%, 67.78% and 100%, respectively. Therefore, the current method can be employed for the direct detection of B. cereus and its enterotoxigenic genes in the meat and meat products without going for isolation and identification procedures and the method can be extended to other foods as well.