Hoefel Daniel, Grooby Warwick L, Monis Paul T, Andrews Stuart, Saint Christopher P
The Cooperative Research Centre for Water Quality and Treatment, Australian Water Quality Centre, SA Water Corporation, Salisbury, South Australia 5108, Australia.
J Microbiol Methods. 2003 Dec;55(3):585-97. doi: 10.1016/s0167-7012(03)00201-x.
Maintaining optimal conditions in catchments or distribution systems relies heavily on water authorities having access to rapid and accurate water quality data, including an indication of bacteriological quality. In this study, the BacLight bacterial viability kit and carboxyfluorescein diacetate (CFDA) were coupled with flow cytometry (FCM) for rapid detection of physiologically active bacteria from raw and potable waters taken from various locations around South Australia. Results were compared to the direct viable count (DVC) and quantitative DVC (qDVC), in addition to the culture-based methods of the heterotrophic plate count (HPC) and a commercial SimPlate technique. Raw and potable water analysis revealed that DVC and culture-based techniques reported significantly fewer viable bacteria compared to the number of physiologically active bacteria detected using the rapid FCM assays, where this difference appeared to be nonlinear across different samples. Inconclusive results were obtained using qDVC as a viability assay. In particular, HPC results were 2-4 log orders of magnitude below that reported by the FCM assays for raw waters. Few bacteria in potable waters examined were culturable by HPC, even though FCM assays reported between 5.56 x 10(2) and 3.94 x 10(4) active bacteria ml(-1). These differences may be attributed to the presence of nonheterotrophic bacteria, sublethal injury or the adoption of an active but nonculturable (ABNC) state.
在集水区或供水系统中维持最佳条件在很大程度上依赖于水务部门能够获取快速且准确的水质数据，包括细菌学质量指标。在本研究中，将BacLight细菌活力检测试剂盒和羧基荧光素二乙酸酯（CFDA）与流式细胞仪（FCM）相结合，用于快速检测从南澳大利亚各地采集的原水和饮用水中的生理活性细菌。除了基于培养的异养平板计数（HPC）方法和一种商业SimPlate技术外，还将结果与直接活菌计数（DVC）和定量DVC（qDVC）进行了比较。原水和饮用水分析表明，与使用快速FCM检测法检测到的生理活性细菌数量相比，DVC和基于培养的技术报告的活菌数量明显较少，而且这种差异在不同样本中似乎是非线性的。使用qDVC作为活力检测方法得到的结果不明确。特别是，对于原水，HPC结果比FCM检测法报告的结果低2至4个对数数量级。尽管FCM检测法报告每毫升饮用水中有5.56×10²至3.94×10⁴个活性细菌，但通过HPC可培养的饮用水中的细菌很少。这些差异可能归因于非异养细菌的存在、亚致死损伤或处于活性但不可培养（ABNC）状态。
