湛江水产品中大肠菌群的分离鉴定与分类研究

    Isolation, identification and classification of coliforms from aquatic products in Zhanjiang

    • 摘要: 水产品中大肠菌群超标现象较为常见,为了更好地控制水产品中微生物安全,对湛江部分水产品中的大肠菌群进行分离、鉴定和分类研究。2012 年11 月耀2013 年1 月,从湛江地区采集及获得的55 份大肠菌群阳性水产品样品中分离纯化得到65 株菌,通过常规生化鉴定和VITEK2 系统鉴定,最终确定63 株分别属于8 种大肠菌群,其中弗氏柠檬酸杆菌24 株、大肠埃希氏菌14 株、阴沟肠杆菌13 株、肺炎克雷伯氏菌7 株、其他大肠菌类型5 株,分别占菌株鉴定总数的38.10%、22.22%、20.63%、11.11%、7.93%,另有2 株细菌未鉴定出所属大肠菌类型。不同种类水产品均检出弗氏柠檬酸杆菌;冻罗非鱼片大肠菌群主要为弗氏柠檬酸杆菌和阴沟肠杆菌,占本样品检出菌株的77.27%;而鲜活对虾和贝类大肠菌群类型主要为弗氏柠檬酸杆菌和大肠埃希氏菌,占本类样品检出菌株的65.79%;对于冷冻水产品,均未检出大肠埃希氏菌,未经加工的水产品较加工水产品大肠菌群种类多。

       

      Abstract: Aquatic products are prone to be contaminated by coliforms. In order to better control the microbial safety of aquatic products, isolation, identification and classification of coliforms from aquatic products in Zhanjiang were conducted. 55 aquatic samples with coliforms in Zhanjiang from Nov 2012 to Jan 2013 were collected and 65 strains of coliforms were isolated and identified by biochemical test and VITEK2 system, 63 strains were confirmed to be 8 species of coliforms, in which 24 strains belonged to Citrobacter freundii, 14 strains belonged to Escherichia coli, 13 strains belonged to Enterobacter cloacae, 7 strains belonged to Klebsiella pneumoniae and 5 strains belonged to other types of bacteria, accounting for 38.10%, 22.22%, 20.63%, 11.11% and 7.93% of the totally isolated strains, respectively, and 2 strains were unknown. Accordingly, C. freundii was found in all kinds of those samples, and the frozen tilapia fillet mainly contained C. freundii and E. cloacae, totally taking 77.27% of the bacteria found, while the fresh white shrimp and shellfish were mainly contaminated by C. freundii and E.coli, totally taking 65.79% of the bacteria found, while E. coli was not found in all of the frozen aquatic products. And more species of coliforms were found in raw aquatic products than those in processed aquatic products.