矿泉水和山泉水中铜绿假单胞菌污染调查及分离菌株毒力基因与耐药性分析

The pollution survey of Pseudomonas aeruginosa in mineral water and spring water and the analyses of virulence genes and antibiotic resistance of the isolates

【目的】初步掌握全国矿泉水和山泉水生产过程中铜绿假单胞菌(Pseudomonas aeruginosa)的污染情况。分析矿泉水与山泉水中铜绿假单胞菌的致病性与耐药性。【方法】研究通过对广西、湖北、云南等全国9个省36家水厂进行采样,共采集108个样本,并根据《饮用天然矿泉水检测方法》国家标准(GB/T 8538-2008)检测其铜绿假单胞菌的污染率、污染水平。对分离出的铜绿假单胞菌菌株进行毒力基因与药敏实验。【结果】全国矿泉水水源水、活性碳过滤后水、成品水的污染率分别为16.7%、16.7%、0,污染水平分别为3.7、2.0、0 CFU/250 m L。全国山泉水水源水、活性碳过滤后水、成品水的污染率分别为66.7%、83.3%、5.6%,污染水平分别为5.1、7.3、2.0 CFU/250 m L。对所分离出的36株铜绿假单胞菌进行毒力基因检测和药敏试验显示:exo U、exo S、phz M、tox A、las B检出率分别为25.0%、75.0%、100%、88.8%、100%,但对美国国家临床实验室标准化委员会标准中14种抗生素均无耐药性。【结论】山泉水水源水、活性碳过滤后水、成品水污染率明显高于矿泉水,但污染水平均较低,无大于40.0 CFU/250 m L样品检出。山泉水活性碳过滤后污染率最高,表明大部分企业在活性碳过滤环节存在污染问题。毒力基因exo U、exo S、phz M、tox A、las B在分离到的36株铜绿假单胞菌检出率高,但分离到的菌株对所选取的14种抗生素均无耐药性。

[Objective] This experiment was made to obtain a preliminary understanding of pollution of Pseudomonas aeruginosa in the production process of mineral water and spring water. Pathogenicity and antibiotic resistance ofP. aeruginosa of mineral water and spring water were analyzed. [Methods] This experiment based on 108 samples from 36 mineral water and spring water factories in 9 provinces. According to the methods for examination of drinking natural mineral water （GB/T8538-2008）, the pollution rates and pollution levels ofP. aeruginosa had been obtained. The tests of virulence gene and antibiotic resistance were tested on collected P. aeruginosa isolates. [Results] The pollution rates of source water, activated carbon filtered water and finished products of mineral water were 16.7%, 16.7%, 0 respectively. The pollution levels of source water, activated carbon filtered water and finished products of mineral water were 3.7, 2.0, 0 CFU/250 mL respectively. The pollution rates of source water, activated carbon filtered water and finished products of spring water were 66.7%, 83.3% and 5.6% respectively. The pollution levels of source water, activated carbon filtered water and finished products of spring water were 5.1, 7.3, 2.0 CFU/250 mL respectively. The virulence gene and antibiotic resistance tests of 36 P. aeruginosa isolates showed that the detection rates of exoU, exoS, phzM, toxA and lasB were 25.0%, 75.0%, 100%, 88.8%, 100% respectively; 36 P. aeruginosa strains were sensitive to 14 kinds of antibiotics which were selected according National Committee for Clinical Laboratory Standards of The United States of America. [Conclusion] The pollution rates of source water, activated carbon filtered water and finished products of spring water were significantly higher than mineral water. Both the pollution levels of 2 kinds of water samples were relatively low and there was no greater than 40.0 CFU/250 mL of the sample. The activated carbon filtered water of spring water was the highest pollution rate among all samples, which indicated that most of the factories had some microbial pollution in the activated carbon filter link. The high detection rates of virulence genes, including exoU, exoS, phzM, toxA and lasB in 36 strains of collected P. aeruginosa were analysed. All 36 isolates of collected P. aeruginosa were sensitive to 14 kinds of antibiotics.