惠州市熟肉制品中金黄色葡萄球菌污染状况及PFGE分型

目的 研究惠州市熟肉制品中金黄色葡萄球菌(Staphylococcus aureus, SA)污染状况及脉冲场凝胶电泳（pulsed-field gel electrophoresis, PFGE）分型及分布特点,建立本地区SA的PFGE分型数据库。为开展食品安全风险评估和预防控制相关食源性疾病提供科学依据。方法 按照GB 4789.10《食品安全国家标准食品微生物学检验金黄色葡萄球菌检验》方法,对惠州市熟肉制品进行SA检测并对检出的菌株进行葡萄球菌肠毒素测定;应用PFGE分型技术对检出的菌株进行电泳分析获得指纹图谱,并用BioNumerics软件进行聚类分析。结果 惠州市2014—2017年共监测572份熟肉制品,检出金黄色葡萄球菌污染41份,检出率7.17%,其中含葡萄球菌肠毒素17株,检出率为41.46%;41株SA经聚类分析得到34个PFGE型别,菌株间相似性系数在51.70%~100.00%之间。结论 惠州市熟肉制品存在一定程度SA污染,且SA的PFGE分型型别较多,菌型分散,部分菌株之间存在一定程度的相关性,未发现单个型别的菌株流行的迹象。PFGE对SA同源性分析,评价SA的流行趋势、分布特点和相关食源性疾病的溯源工作具有重要的意义。

Contamination of Staphylococcus aureus in cooked meat products and molecular typing by PFGE in Huizhou

Objective Tounderstand the contamination of Staphylococcus aureus (SA) in cooked meat products and the classification and distribution of SA by pulsed-field gel electrophoresis (PFGE), and to establish the PFGE typing database of SA in this area so as to provide an evidence for the risk assessment of food safety and the prevention and control of foodborne diseases. Methods According to “Food microbiological examination of national food safety standard for Staphylococcus aureus” (GB 4789-10), the cooked meat products were tested for SA,and then SA enterotoxin(SE) was detected. The PFGE typing technique was used to analyze the strains to obtain fingerprints, and the clustering analysis of which was performed by BioNumerics software. Results A total of 572 cooked meat products were detected in Huizhou City from 2014 to 2017, and 41 strains of SA were isolated with the total detection rate of 7.17%, and 17 strains of which contained SE, with the detection rate of 41.46%. Totally 34 PFGE types were obtained by the cluster analysis among 41 strains of SA, and the similarity coefficient among the strains was 51.70%-100.00%. Conclusion sThere is a certain degree of SA pollution in cooked meat products in Huizhou City, and the PFGE typing of SA in cooked meat products is fairy abundant with many different molecular type categories, and the bacteria type is dispersed and some strains have some correlation. No signs of prevalence of individual strains are found.PFGE is a reliable method to analyze the homology of SA and it has great significance for the trend, distribution and traceability of related foodborne diseases.