水产品批发市场中抗生素抗性基因的污染分析

Research of the Pollution of Antibiotic Resistance Genes in Aquatic Products Wholesale Market

为了探究待售水产品中抗生素抗性基因(Antibiotic resistance genes,ARGs)在水产品批发市场中的扩散污染情况,选取上海市3个大型水产品批发市场作为研究对象,采用PCR的方法,对市场内部和市场附近的排污沟表层淤泥中5大类(4种磺胺类、8种四环素类、6种β-内酰胺类、5种氯霉素类、4种链霉素类)共27种ARGs进行了检测,并利用PCR-DGGE技术分析了细菌种群多样性。结果显示共有17种ARGs在批发市场淤泥中被检出,其中磺胺类、四环素类和链霉素类ARGs的检出率较高且检出种类较多,表明水产品批发市场含有种类丰富的ARGs,水产品以磺胺类、四环素类和链霉素类ARGs污染为主。对市场外围的检测显示市场外围区域ARGs的种类分布略低于市场内部,表明水产品批发市场中ARGs的存在会通过污水排放途径扩散到周边环境。DGGE图谱的分析结果显示,3个批发市场污泥样品细菌种类差异性较大,表明环境中ARGs的种类分布与细菌的种类并无直接关联。本研究表明水产品携带的ARGs会扩散到水产品批发市场中,导致水产品批发市场成为ARGs的重要储存库,以此造成的污染会进一步传播到周边环境,此外,这些种类丰富的ARGs重新扩散到待售水产品中的风险很大,需引起人们足够的重视。

In order to investigate the dissemination of antibiotic resistance genes （ARGs） from contaminated aquatic products in aquatic products wholesale market,this study targeted three large-scale aquatic products wholesale markets as research object and collected mixed sewage ditch sediment in and around the three markets separately as test samples. With the help of PCR, this study detected five categories, （four kinds of sulfonamides,eight kinds of tetracyclines, six kinds of β-lactams, five kinds of chloramphenicol,and four kinds of streptomycin） , in which there is a total of twenty seven kinds of ARGs. Moreover,PCR-DGGE technique was utilized to analyze the diversity of bacteria community in the sample. The results showed that seventeen kinds of ARGs were detected in aquatic products wholesale markets and they all contained multiple types of tetracyclines, sulfonamides, and streptomycin ARGs, which accounted for the conclusion that there was a great variety of ARGs types in aquatic products wholesale market and these three kinds of ARGs were major ones in aquatic products. Sample testing of sewage ditch sediment near the markets showed that ARGs in surrounding place was slightly lower than ARGs in markets, indicating that the occurrence of ARGs in markets would pollute surrounding environment by sewage discharge. Analysis of the results of DGGE profiles showed that though ARGs distributed in three aquaculture markets shared similarities, the distribution of bacterial types between three markets were great different, displaying that there was no direct relationship between the types of ARGs and bacterial types. This work noted that aquatic products wholesale market has became a important receiver of ARGs through the dissemination of ARGs from contaminated aquatic products, and thisreceiver would not only pollute surrounding environment by sewage discharge to some extent, particularly, resulting a huge risk to pollute aquatic products again, hence needing more attention.