Molecular characterization of Bacillus cereus toxigenic strains isolated from different food matrices in Jordan

Bacillus cereus is increasingly recognized as one of the causative agents of food poisoning in different parts of the world. In this study, molecular characterization of B. cereus toxigenic strains isolated from food in Jordan was performed. A total of 202 food samples were collected from local markets and restaurants. B. cereus was found in 23.3% (47) of the food samples. The hemolytic enterotoxin hblA, hblC, and hblD were detected in 40.4%, 36.5%, and 75% of the isolates, respectively. Combination of all three hbl genes was detected in 19 isolates (36.5%). The nonhemolytic enterotoxin nheA, nheB, and nheC were detected in 61.5%, 92.3%, and 92.3% of the isolates, respectively. All three nhe genes were detected in 27 isolates (51.9%). The six enterotoxin genes (hemolysin BL [HBL] and NHE complexes) were detected in 25% of isolates. The cytK gene was detected in 53.8% of B. cereus isolates, whereas the bceT gene was detected in 69.2%. Only four emetic toxin-producing isolates were found to carry all the three genes of NHE complex, but none of the HBL complex ones. The B. cereus Enterotoxin-Reversed Passive Latex Agglutination assay results were strongly correlated with molecular detection of the L(2) part of the HBL complex (p≤0.01). This study demonstrated the occurrence of potentially enterotoxic and emetic toxic B. cereus isolates in the food samples analyzed from Jordan.