Isolation, Conventional and Molecular Identification of Bacillus Cereus and its Incidence in Beef Samples

Abstract

The current study was conducted to examine the presence of Bacillus cereus in beef samples. B. cereus was isolated from 50 samples among them 29 (58 %) of the samples were positive. A huge number of bacterium was observed in beef samples. Isolates were analyzed through different biochemical tests like catalase, citrate utilization, glucose/galactose fermentation, oxidase, motility and Gram staining. A number of isolates were discovered positive when checked by biochemical tests as well as through PCR (Multiplex polymerase chain reaction). Major degree of genetic similarity is found in the group of Bacillus cereus bacteria. Thus, to efficiently identify and differentiate the Bacillus cereus group, a multiplex polymerase chain reaction method was suggested for immediate detection using the groEL and gyrB gene as diagnostic markers. For B. cereus group groEL gene of 400 bp and 475 bp amplicon size for gyrB gene of the B. cereus was yielded. In result the multiplex PCR is proved efficient, simple and rapid for the immediate identification of B. cereus group bacteria in beef samples.