生食蔬菜模拟污染米饭样本中蜡样芽胞杆菌和呕吐毒素基因分布状况研究  

Distribution of Bacillus cereus and vomiting toxin gene in cooked rice samples which simulated contaminated by raw vegetables

作　　者：李颖[1,2] 全菲[1,2] 崔涓涓 王园园[1,2] 王苗[1,2] 荆红波[1,2] 刘盛田[1,2] 彭涛[1] 逄波 LI Ying;QUAN Fei;CUI Juanjuan;WANG Yuanyuan;WANG Miao;JING Hongbo;LIU Shengtian;PENG Tao;PANG Bo(Shunyi District Center for Disease Control and Prevention,Beijing 101300,China;Workstation for Microbial Infectious Disease,Beijing 101300,China;Baotou Medical College,Inner Mongolia Baotou 010040,China;National Institute for Communicable Disease Control and Prevention,Beijing 102206,China)

机构地区：[1]北京市顺义区疾病预防控制中心,北京101300 [2]北京市顺义区疾病预防控制中心微生物感染性疾病检测工作站,北京101300 [3]包头医学院,内蒙古包头010040 [4]中国疾病预防控制中心传染病预防控制所,北京102206

出　　处：《中国食品卫生杂志》2024年第4期440-444,共5页Chinese Journal of Food Hygiene

基　　金：基于病原细菌基因组的传染病网络化监测技术体系研究(2018ZX10714-002-001)。

摘　　要：目的分析被生食蔬菜模拟污染的米饭样本中蜡样芽胞杆菌(Bc)和呕吐毒素基因(ces)的分布状况,为Bc食物中毒科学防控提供基础数据。方法采集生食蔬菜样本50件,每件样本用0.85%生理盐水盥洗后污染“新煮熟米饭”,置于30℃、70%RH培养箱中放置24 h。对生食蔬菜和“污染米饭”进行Bc的定量计数、荧光PCR检测和数字PCR检测。对基于不同采集地点、不同蔬菜类型分组的生食蔬菜样本和及被其污染的“污染米饭”的各项检出率指标进行统计学分析。结果生食蔬菜样本中Bc检出率为80.00%(40/50),ces基因和Bac16s RNA基因检出率分别为0(0/50)和10.00%(5/50);“污染米饭”样本Bc检出率为94.00%(47/50),ces基因和Bac16s RNA基因检出率分别为14.00%(7/50)和90.00%(45/50)。采集自农贸市场和农户土地的2组生食蔬菜中Bc检出率差异有统计学意义(χ^(2)=11.063,P=0.00088校正),被上述2组生食蔬菜类污染的“污染米饭”Bac16s RNA基因检出率和ces基因检出率差异均有统计学意义(χ^(2)=3.926,P=0.0475校正;χ^(2)=5.444,P=0.0196校正)。7件“污染米饭”基于荧光PCR检测ces基因阳性,Ct值介于24.12~37.73,数字PCR结果介于6.8 copes/μL~6.2×10^(6)copes/μL。结论被生食蔬菜模拟污染的米饭样本可具有导致Bc食物中毒风险的病原学特征。Objective To analyze the distribution of Bacillus cereus(B.cereus)and vomiting toxin gene(ces)in cooked rice samples which simulated contaminated by raw vegetables,and provide basic data for prevention of food poisoning caused by B.cereus.Methods Fifty raw vegetable samples were collected in this study.Simulate method was as contaminated“freshly cooked rice”with 0.85%physiological saline solution from washing raw vegetables,and then place it in a 30℃70%RH environment for 24 h to prepare a sample of“contaminated rice”.Plate counting,real time PCR and digital PCR were performed for raw vegetable and“contaminated rice”samples.Statistical analysis was performed on the detection rates grouped by different vegetable types for raw vegetable samples and“contaminated rice”contaminated with them.Results The detection ratios of B.cereus,ces gene and Bac16s RNA gene in raw vegetables was 80.00%(40/50),0(0/50)and 10.00%(5/50).The detection ratios of B.cereus,ces gene and Bac16s RNA gene in“contaminated rice”was 94.00%(47/50),14.00%(7/50)and 90.00%(45/50).There was significant difference in the detection ratio of B.cereus between raw vegetables collected from agricultural markets and farmland(χ^(2)=11.063,P=0.00088 correction),and the difference in the detection rates of Bac16s RNA gene and ces genes in“contaminated rice”contaminated with the two groups of raw vegetables mentioned above is statistically significant(χ^(2)=3.926,P=0.0475 correction;χ^(2)=5.444,P=0.0196 correction).Seven“contaminated rice”were tested positive for the ces gene using real time PCR,with Ct values ranging from 24.12 to 37.73,and digital PCR results ranging from 6.8 copes/μL-6.2×10^(6)copes/μL.Conclusion Cooked rice samples which simulated contaminated by raw vegetables might be has the etiology characteristics that lead to a risk of food poisoning caused by B.cereus.

关 键 词：蜡样芽胞杆菌 米饭 生食蔬菜 呕吐毒素 

分 类 号：R155[医药卫生—营养与食品卫生学]