Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Diagonal 643, 08028 Barcelona, Spain; Bluephage S.L., Gavà 4, 08820, El Prat de Llobregat, Barcelona, Spain; The Water Research Institute, University of Barcelona, Montalegre 6, 08001 Barcelona, Spain.
Bluephage S.L., Gavà 4, 08820, El Prat de Llobregat, Barcelona, Spain.
Sci Total Environ. 2022 Sep 10;838(Pt 3):156381. doi: 10.1016/j.scitotenv.2022.156381. Epub 2022 May 31.
In the last decade coliphages have been included in many water quality regulations as viral faecal indicators. However, the standardised methods used to detect and quantify coliphages differ in bacterial host strains, culture media and techniques. In this comparative study, 100 mL samples of mineral drinking water, river water and wastewater were analysed with International Organization for Standardization (ISO) standard methods, with United States-Environmental Protection Agency (U.S. EPA) based methods as well as commercial kits combining a single agar layer (SAL) assay with ISO bacterial host strains. The three methods gave similar counts (p-value>0.05) for somatic and total coliphages in the matrices with less than 100 PFU/100 mL, whereas for F-specific coliphages, the U.S. EPA method provided statistically significant lower numbers (p-value<0.05) than the other two protocols, possibly because it uses a different bacterial host strain (Escherichia coli HS (pFamp) R vs. the ISO strain Salmonella enterica serovar Typhimurium WG49). In samples with more than 100 PFU/100 mL, the ISO method yielded higher counts of somatic coliphages than the other two protocols (p-value<0.05). As the three methods provided similar results in clean water, the approach combining a SAL assay with the ISO bacterial host strain could be a useful option for coliphage analysis in this type of sample, as it does not require a concentration step.
在过去的十年中，噬菌体已被纳入许多水质法规，作为病毒粪便指示物。然而，用于检测和定量噬菌体的标准化方法在细菌宿主株、培养基和技术方面存在差异。在这项比较研究中，用国际标准化组织（ISO）标准方法、美国环保署（U.S. EPA）基于方法以及将单一琼脂层（SAL）测定法与 ISO 细菌宿主株相结合的商业试剂盒，对 100 毫升矿化饮用水、河水和废水样本进行了分析。三种方法在低于 100 PFU/100 毫升的基质中对体细胞和总噬菌体的计数相似（p 值>0.05），而对于 F 特异性噬菌体，U.S. EPA 方法提供的数量明显低于其他两种方案（p 值<0.05），可能是因为它使用了不同的细菌宿主株（大肠杆菌 HS（pFamp）R 与 ISO 菌株沙门氏菌肠亚种 Typhimurium WG49）。在高于 100 PFU/100 毫升的样本中，ISO 方法比其他两种方案得出的体细胞噬菌体计数更高（p 值<0.05）。由于三种方法在清洁水中提供了相似的结果，因此将 SAL 测定法与 ISO 细菌宿主株结合的方法可能是这种类型样本中噬菌体分析的一种有用选择，因为它不需要浓缩步骤。
