1. Canary in the coliform mine: Exploring the industrial application limits of a microbial respiration alarm system
- Author
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Marthinus J. Booysen, Wendy Stone, Gideon M. Wolfaardt, and Tobi M. Louw
- Subjects
Canaries ,Marine and Aquatic Sciences ,030501 epidemiology ,Wastewater ,chemistry.chemical_compound ,Bioreactors ,Water Quality ,Natural Resources ,Anaerobiosis ,0303 health sciences ,Multidisciplinary ,Physics ,Classical Mechanics ,Eukaryota ,Contamination ,Pulp and paper industry ,Pollution ,6. Clean water ,Chemistry ,Carbon dioxide ,Physical Sciences ,Vertebrates ,Water Resources ,Medicine ,0305 other medical science ,Water Microbiology ,Anaerobic exercise ,Environmental Monitoring ,Research Article ,Freshwater Environments ,Science ,Partial Pressure ,12. Responsible consumption ,Birds ,03 medical and health sciences ,Rivers ,Surface Water ,Respiration ,Bioreactor ,Pressure ,Animals ,Ecosystem ,Bacteria ,030306 microbiology ,Drinking Water ,Ecology and Environmental Sciences ,Water Pollution ,Chemical Compounds ,Organisms ,Aquatic Environments ,Biology and Life Sciences ,Carbon Dioxide ,Bodies of Water ,Fecal coliform ,chemistry ,13. Climate action ,Greenhouse gas ,Biofilms ,Amniotes ,Earth Sciences ,Environmental science ,Water quality ,Hydrology ,Zoology - Abstract
Fundamental ecological principles of ecosystem-level respiration are extensively applied in greenhouse gas and elemental cycle studies. A laboratory system termed CEMS (Carbon Dioxide Evolution Measurement System), developed to explore microbial biofilm growth and metabolic responses, was evaluated as an early-warning system for microbial disturbances in industrial settings: in (a) potable water system contamination, and (b) bioreactor inhibition. Respiration was detected as CO2 production, rather than O2 consumption, including aerobic and anaerobic metabolism. Design, thresholds, and benefits of the remote CO2 monitoring technology were described. Headspace CO2 correlated with contamination levels, as well as chemical (R2 > 0.83–0.96) and microbiological water quality indicators (R2 > 0.78–0.88). Detection thresholds were limiting factors in monitoring drinking water to national and international standards (0 CFU/100 mL fecal coliforms) in both open- (>1500 CFU/mL) and closed-loop CO2 measuring regimes (>100 CFU/100 mL). However, closed-loop detection thresholds allow for the detection of significant contamination events, and monitoring less stringent systems such as irrigation water (2 fluctuations from chemical CO2 dynamics, to optimize this real-time, sustainable, low-waste technology, facilitating timeous responses to biological disturbances in bioreactors.
- Published
- 2020