南京市4个污水处理厂的活性污泥中细菌的分离鉴定和抗生素耐药性分析

通过16S rDNA序列分析对南京CN、CE、JN和JM这4个污水处理厂的活性污泥中分离的细菌进行鉴定,采用Kirby-Bauer纸片琼脂扩散法分析细菌的抗生素耐药性,目的是阐明该地区污水处理厂活性污泥中细菌抗生素耐药性现状,探索污水及污泥的潜在环境风险.4个污水处理厂分别分离到7、9、8和11株菌落形态不同的细菌,上述35株细菌分属25个种,17个属.抗生素耐药性分析显示,97.1%的菌株具有抗生素耐药性,80%菌株具有多重耐药性.分离菌株对氨苄西林、卡那霉素、氯霉素、链霉素、庆大霉素、四环素、红霉素和大观霉素的耐药率分别为71.4%、37.1%、37.1%、57.1%、34.3%、68.6%、94.3%和65.7%.结果表明活性污泥中细菌耐药性严重;不同菌株间的耐药性分析显示,危害水产养殖业的病原菌气单胞菌具有严重的多重耐药性,所有芽孢杆菌对氯霉素、链霉素和庆大霉素敏感;污水处理厂应加强出水的消杀工作,避免二次污染.

Isolation and Identification of Bacteria in the Activated Sludge from Four Sewage Treatment Plants in Nanjing City and Its Antibiotic Resistance Analysis

Bacteria were isolated from the activated sludge of CN, CE, JN and JM Sewage Treatment Plants (STPs) in Nanjing city and identified by 16S rDNA sequence analysis. The antibiotic resistance analysis of the isolated bacteria was conducted by Kirby-Bauer Disc Agar Diffusion Method. The objective of this study is to clarify the current state of bacteria antibiotic resistance from the four STPs and analyze the potential environmental risk of the produced waste water and the sludge. The 7, 9, 8 and 11 bacterial strains with different morphology were respectively isolated from the above four sample sites, which belonged to 25 species and 17 genera. Antibiotic resistance analysis indicated that 97.1% of isolates had antibiotic resistance and 80% of isolates had multi-antibiotic resistance. The drug resistance rates were 71.4%, 37.1%, 37.1%, 57.1%, 34.3%, 68.6%, 94.3% and 65.7% of ampicillin(AM), kanamycin(KAN), chloromycetin(CHL), streptomycin(STR), gentamicin(GEN), tetracycline(TET), erythromycin(EM) and spectinomycin(SPE), respectively. It indicated that the activated sludge from the four STPs had high antibiotic resistance. The drug resistance analysis between different bacteria indicated that the genus Aeromonas, an aquacultural pathogen, had multi-antibiotic resistance, while all of Bacillus were sensitive to CHL, STR and GEN. The STPs should enhance the sterilization of effluent water to avoid the second pollutions.