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Evaluation of an Instrument to Monitor Microbial Contamination of Recovered Water
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Abstract
NASA-Marshall Space Flight Center (MSFC) has an interest in an automated in-line monitor that can detect the presence of microbial contamination in recovered water. Ideally, this system should also be able to identify and enumerate the microbial contaminant. The Viable Microbial Monitor (VM2) is based on conductance microbiology which depends on the well documented ability of microorganisms to change the electrochemical properties of their growth medium during incubation. The VM2 is intended for the rapid detection of bacterial or fungal contamination in water and other samples.
From October 1992 to July 1993, NASA-MSFC sponsored a Microbial In-line Monitor (MIM) study to evaluate the VM2 for its ability to detect ten microorganism species (9 bacteria and 1 yeast) recovered from Water Recovery Tests (WRT) conducted at MSFC. These WRT isolates may represent the microbes that have potential to contaminate a water recovery system. Three temperatures (30, 35, and 40°C) and three media (m-Plate Count Broth [HPC], 1/2 strength Tryptic Soy Broth [½TSB], and R2A Broth) were used for the evaluation. The final outcome of this study was to select 3 of the 10 microbes for further study.
Results showed that Klebsiella oxytoca, Staphylococcus epidermidis, and Corynebacterium xerosis gave the greatest overall response. Detection time ranged from approximately 5.4 hours (K. oxytoca) to 15.8 hours (C. xerosis). The change in conductance ranged from 143 μSiemens (K. oxytoca) to 20 μSiemens (C. xerosis). For each microbial species selected, reproducible results were obtained more rapidly than that obtained by conventional assays. Significantly different conductance growth patterns were observed which may permit subsequent identification.
Data and graphs representing microbial detection, growth rates, growth patterns, and reproducibility will be presented. In addition, thoughts on future research and applications will be considered.
Citation
Snyder, G., O'Leary, J., Pyle, B., Roman, M. et al., "Evaluation of an Instrument to Monitor Microbial Contamination of Recovered Water," SAE Technical Paper 941389, 1994, https://doi.org/10.4271/941389.Also In
References
- Boehm, A.M. Colling, A.K. Jr. Heldmann M.J. Steel J.W. Shaw R.G. 1992 Space Station water processor: Current flight design SAE Technical Paper Series 921112 . 22nd International Conference on Environmental Systems Seattle, WA July 13-16 1992
- Niu, W. Burchfield D. Snyder G. Conklin K. 1990 Development of a Water Quality Monitor for Space Station Freedom life support system SAE Technical Paper Series 901426 . 20th International Conference on Environmental Williamsburg, VA July 9-12 1990
- Snyder, G. O'Leary J.D. Mount B. Pyle B. 1992 Microbial screening of water supplies for spaceflight missions. AIAA 92-1605 American Institute of Aeronautics and Astronautics Space Programs and Technologies Conference Huntsville, AL March 24-27 1992
- Snyder, G. O'Leary J.D. 1992 Instrumentation for microbial monitoring of decontamination of biocide system effectiveness SAE Technical Paper Series 921233 . 22nd International Conference on Environmental Systems Seattle, WA July 13-16 1992
- Snyder, G. Niu W. Burchfield D. 1991 Water quality monitoring on Space Station Freedom Proceedings of the Marchem '91 Workshop on Marine Chemistry 1991 Office of the Chief of Naval Research Arlington, VA June 1992
- Coombs, P. 1990 Detecting Salmonella by conductance 241 242 Food technology international Europe 1990
- Baynes, N.C. Comrie J. Prain J.H. 1983 Detection of bacterial growth by the Malthus conductance meter Medical Laboratory Sciences 40 149 158
- Cady, P. 1975 Rapid automated bacterial identification by impedance measurements 73 79 Heden C.G. Illeni T. In New approaches to the identification of microorganisms Wiley New York
- Easter, M.C. Gibson D.M. 1989 Early detection of microorganisms by electrical measurements 57 100 26 Adams M.R. Hope C.F.A. In Rapid methods in food microbiology: Progress in industrial microbiology Elsevier Amsterdam
- Hadly, W.K. Senyk G. 1975 Early detection of microbial metabolism and growth by measurement of electrical impedance 12 21 Schlessinger D. In Microbiology - 1971 American Society for Microbiology Washington, D.C
- Richards, J.C.S. Jason A.C. Hobbs G. Gibson D.M. Christie R.H. 1978 Electronic measurement of bacterial growth Journal of Physics 11 560 568
- Ur, A. Brown D.F.J. 1975 Monitoring of bacterial activity by impedance measurements 61 71 In New approaches to the identification of microorganisms Wiley New York
- Wheeler, T.G. Goldschmidt M.C. 1975 Determination of bacterial cell concentrations by electrical measurements Journal of Clinical Microbiology 1 25 29
- Snyder, G. O'Leary J.D. 1992 Test report: Evaluation of a Microbial In-line Monitor Perkin-Elmer Pomona
- Snyder, G. O'Leary J.D. Pyle B.H. 1993 Microbial In-line Monitor (MIM) task 1: Characterize ten representative water recovery test candidate microorganisms Marshall Space Flight Center Orbital Sciences Corporation Pomona, CA
- Snyder, G. Pyle B.H. O'Leary J. Liu K. Roman M.C. 1993 Early detection of microbes from prototype water recovery system samples using real time conductivity instrumentation Sae Technical Paper Series 932179 . 23rd International Conference on Environmental Systems Colorado Springs, CO July 12-15 1993