Contamination Status and Genotype Detection of Emetic Toxin Gene of Bacillus cereus in Ready-to-eat Food Imported from Yunnan Border Trade

In order to investigate the contamination status and the genotype carrying of emetic toxin gene of Bacillus cereus in the imported ready-to-eat foods from border trade in Yunnan,224 commercial samples were collected from the distribution points of import food trade(borders,farmers’ markets,import and export product stores,etc.)imported from various ports on the Yunnan border. The isolated Bacillus cereus was identified by VITEK 2 compact automatic microbial identification system and double real-time fluorescent polymerase chain reaction(Dual real-time PCR)technology,and the emetic toxin gene in the positive strains were detected. The results showed that,the detection rate of Bacillus cereus was 20.09%(45/224)in the collected samples,and the detection rate of Tianbao,Jinshuihe,Ruili and Wanding ports were all higher than 10%. Food categories with high detection rate were:Pickles 60%(3/5),condiments 50%(15/30),aquatic products and their products 46.67%(7/15). A total of 113 strains of Bacillus cereus were isolated from 45 positive samples,of which the carrying rate of emetic toxin gene cesB was 0.88%(1/113),and the carrying rate of emetic toxin gene was low,but the risk of contamination by Bacillus cereus could not be ignored. The results of this study would provide a theoretical basis for the safety and food-borne disease surveillance and prevention of imported food from border trade.