为探究云南省边贸进口即食食品中蜡样芽胞杆菌的污染状况及其呕吐毒素基因型携带情况,从云南边境各口岸进口食品贸易集散点(边民互市点、农贸市场以及进出口产品店等地)共采集市售包装样品224份。通过VITEK 2 compact全自动微生物鉴定系统和双重实时荧光聚合酶链式反应(Double real-time fluorescent polymerase chain reaction,Dual real-time PCR)技术对分离得到的蜡样芽胞杆菌进行鉴定,并对阳性菌株中的呕吐毒素基因进行检测。结果表明:蜡样芽胞杆菌在所采集样品中的检出率为20.09%(45/224),天保、金水河、瑞丽以及畹町各口岸检出率均高于10%。检出率较高的食品类别为:酱腌菜60%(3/5)、调味品50%(15/30)、水产及其制品46.67%(7/15);从45份阳性样品中共分离出113株蜡样芽胞杆菌,其中呕吐型毒素基因cesB的携带率为0.88%(1/113),呕吐型毒素基因携带率较低,但是蜡样芽胞杆菌的污染风险仍不可忽视。该研究结果对边贸进口食品安全、食源性疾病的监测及预防提供了理论依据。
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.