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Characterizing Microbiome Dynamics – Flow Cytometry Based Workflows from Pure Cultures to Natural Communities
Published on: July 12, 2018
Flow-cytometric total bacterial cell counts as a descriptive microbiological parameter for drinking water treatment
Frederik Hammes1, Michael Berney, Yingying Wang
1Swiss Federal Institute of Aquatic Science and Technology (Eawag), P.O. Box 611, Uberlandstr. 133, CH-8600 Dübendorf, Switzerland.
Water Research
|July 31, 2007
Summary
Total bacterial cell counting using flow cytometry (FCM) offers a rapid and sensitive method for assessing drinking water quality. This approach accurately tracks microbial changes during ozonation, granular active carbon filtration, and ultrafiltration processes.
Area of Science:
- Environmental microbiology
- Water treatment technologies
- Analytical chemistry
Background:
- Conventional heterotrophic plate counts (HPCs) underestimate microbial populations in drinking water.
- Total bacterial cell concentrations are not routinely monitored due to a lack of rapid quantification methods.
- Existing data gaps hinder the demonstration of total cell counts as a practical water quality parameter.
Purpose of the Study:
- To evaluate quantitative flow cytometry (FCM) for rapid and accurate total bacterial cell enumeration in drinking water.
- To assess the impact of ozonation, granular active carbon (GAC) filtration, and ultrafiltration (UF) on microbial populations.
- To compare FCM with traditional HPCs and adenosine tri-phosphate (ATP) measurements.
Main Methods:
- Utilized fluorescence staining with SYBR Green I for microbial cell detection.
- Employed quantitative flow cytometry (FCM) to determine total cell concentrations.
- Analyzed water samples from a pilot drinking water treatment plant employing ozonation, GAC filtration, and UF.
Main Results:
- FCM accurately described the effects of ozonation (cell destruction), GAC filtration (microbial regrowth), and UF (cell removal).
- FCM detected 1-2 log units more cells than conventional HPCs.
- ATP measurements showed interference from extracellular ATP after ozonation.
Conclusions:
- Total cell concentration measured by FCM is a rapid, easy, and sensitive parameter for drinking water analysis.
- FCM provides a descriptive understanding of microbial dynamics throughout key drinking water treatment steps.
- FCM offers a superior alternative to HPCs for comprehensive microbial quality assessment in drinking water.
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