Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water

Zhi Xuan Li; Wei Ma; Yi Jun Kong; Sin Neng Chio; Chang Li Zhang; Chi Tou Lei; She Xia Zhan

doi:doi:10.11648/j.ajep.20221102.14

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Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water

Zhi Xuan Li, Wei Ma, Yi Jun Kong, Sin Neng Chio, Chang Li Zhang, Chi Tou Lei, She Xia Zhan

Published in American Journal of Environmental Protection (Volume 11, Issue 2)

Received: 23 March 2022 Accepted: 8 April 2022 Published: 25 April 2022

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Abstract

The evaluation of measurement uncertainty (MU) is an important method for quantitative determinations derived by microbial cultivation, thus it could further improve the result accuracy. In this study, we aimed to evaluate the MU in total bacteria counts (TBC) in water. Experiments were carried out using Pour Plate Method. The bottom-up approach was used to access the MU of TBC and different mathematical models were set up based on microbial growth principles and test process. Two geometric and five non-geometric progression factors derived from fishbone diagram were selected in these models, especially considering the influence of the bacteria binary fission. The results showed that the calculated value of expanded uncertainty was between 82 and 120CFU/mL when the test result was 100CFU/mL with the 95% confidence level. The geometric progression factor had a greater impact on MU evaluation with almost 80% of contribution, whilst non-geometric progression factor dedicated 60%. Experimental procedures such as sample repeatability, reproducibility and inoculation time should be drawn more attention, thus the accuracy of results could be improved. These innovative models not only reasonable and reliable, but also easy to use. The achievements of this study illustrated that the MU evaluation method could also be applied for analyzing other microbial indicators in water.

Published in	American Journal of Environmental Protection (Volume 11, Issue 2)
DOI	10.11648/j.ajep.20221102.14
Page(s)	32-38
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Measurement Uncertainty, Total Bacteria Count, Geometric Progression, Pour Plate Method

References

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APA Style

Zhi Xuan Li, Wei Ma, Yi Jun Kong, Sin Neng Chio, Chang Li Zhang, et al. (2022). Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water. American Journal of Environmental Protection, 11(2), 32-38. https://doi.org/10.11648/j.ajep.20221102.14

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ACS Style

Zhi Xuan Li; Wei Ma; Yi Jun Kong; Sin Neng Chio; Chang Li Zhang, et al. Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water. Am. J. Environ. Prot. 2022, 11(2), 32-38. doi: 10.11648/j.ajep.20221102.14

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AMA Style

Zhi Xuan Li, Wei Ma, Yi Jun Kong, Sin Neng Chio, Chang Li Zhang, et al. Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water. Am J Environ Prot. 2022;11(2):32-38. doi: 10.11648/j.ajep.20221102.14

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@article{10.11648/j.ajep.20221102.14,
  author = {Zhi Xuan Li and Wei Ma and Yi Jun Kong and Sin Neng Chio and Chang Li Zhang and Chi Tou Lei and She Xia Zhan},
  title = {Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water},
  journal = {American Journal of Environmental Protection},
  volume = {11},
  number = {2},
  pages = {32-38},
  doi = {10.11648/j.ajep.20221102.14},
  url = {https://doi.org/10.11648/j.ajep.20221102.14},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajep.20221102.14},
  abstract = {The evaluation of measurement uncertainty (MU) is an important method for quantitative determinations derived by microbial cultivation, thus it could further improve the result accuracy. In this study, we aimed to evaluate the MU in total bacteria counts (TBC) in water. Experiments were carried out using Pour Plate Method. The bottom-up approach was used to access the MU of TBC and different mathematical models were set up based on microbial growth principles and test process. Two geometric and five non-geometric progression factors derived from fishbone diagram were selected in these models, especially considering the influence of the bacteria binary fission. The results showed that the calculated value of expanded uncertainty was between 82 and 120CFU/mL when the test result was 100CFU/mL with the 95% confidence level. The geometric progression factor had a greater impact on MU evaluation with almost 80% of contribution, whilst non-geometric progression factor dedicated 60%. Experimental procedures such as sample repeatability, reproducibility and inoculation time should be drawn more attention, thus the accuracy of results could be improved. These innovative models not only reasonable and reliable, but also easy to use. The achievements of this study illustrated that the MU evaluation method could also be applied for analyzing other microbial indicators in water.},
 year = {2022}
}

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TY  - JOUR
T1  - Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water
AU  - Zhi Xuan Li
AU  - Wei Ma
AU  - Yi Jun Kong
AU  - Sin Neng Chio
AU  - Chang Li Zhang
AU  - Chi Tou Lei
AU  - She Xia Zhan
Y1  - 2022/04/25
PY  - 2022
N1  - https://doi.org/10.11648/j.ajep.20221102.14
DO  - 10.11648/j.ajep.20221102.14
T2  - American Journal of Environmental Protection
JF  - American Journal of Environmental Protection
JO  - American Journal of Environmental Protection
SP  - 32
EP  - 38
PB  - Science Publishing Group
SN  - 2328-5699
UR  - https://doi.org/10.11648/j.ajep.20221102.14
AB  - The evaluation of measurement uncertainty (MU) is an important method for quantitative determinations derived by microbial cultivation, thus it could further improve the result accuracy. In this study, we aimed to evaluate the MU in total bacteria counts (TBC) in water. Experiments were carried out using Pour Plate Method. The bottom-up approach was used to access the MU of TBC and different mathematical models were set up based on microbial growth principles and test process. Two geometric and five non-geometric progression factors derived from fishbone diagram were selected in these models, especially considering the influence of the bacteria binary fission. The results showed that the calculated value of expanded uncertainty was between 82 and 120CFU/mL when the test result was 100CFU/mL with the 95% confidence level. The geometric progression factor had a greater impact on MU evaluation with almost 80% of contribution, whilst non-geometric progression factor dedicated 60%. Experimental procedures such as sample repeatability, reproducibility and inoculation time should be drawn more attention, thus the accuracy of results could be improved. These innovative models not only reasonable and reliable, but also easy to use. The achievements of this study illustrated that the MU evaluation method could also be applied for analyzing other microbial indicators in water.
VL  - 11
IS  - 2
ER  -

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Author Information

Zhi Xuan Li

Laboratory and Research Centre, The Macao Water Supply Company Limited, Macao SAR, China
Wei Ma

Laboratory and Research Centre, The Macao Water Supply Company Limited, Macao SAR, China
Yi Jun Kong

Laboratory and Research Centre, The Macao Water Supply Company Limited, Macao SAR, China
Sin Neng Chio

Laboratory and Research Centre, The Macao Water Supply Company Limited, Macao SAR, China
Chang Li Zhang

Laboratory and Research Centre, The Macao Water Supply Company Limited, Macao SAR, China
Chi Tou Lei

Laboratory and Research Centre, The Macao Water Supply Company Limited, Macao SAR, China
She Xia Zhan

Laboratory and Research Centre, The Macao Water Supply Company Limited, Macao SAR, China

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APA Style

Zhi Xuan Li, Wei Ma, Yi Jun Kong, Sin Neng Chio, Chang Li Zhang, et al. (2022). Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water. American Journal of Environmental Protection, 11(2), 32-38. https://doi.org/10.11648/j.ajep.20221102.14

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ACS Style

Zhi Xuan Li; Wei Ma; Yi Jun Kong; Sin Neng Chio; Chang Li Zhang, et al. Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water. Am. J. Environ. Prot. 2022, 11(2), 32-38. doi: 10.11648/j.ajep.20221102.14

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AMA Style

Zhi Xuan Li, Wei Ma, Yi Jun Kong, Sin Neng Chio, Chang Li Zhang, et al. Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water. Am J Environ Prot. 2022;11(2):32-38. doi: 10.11648/j.ajep.20221102.14

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@article{10.11648/j.ajep.20221102.14,
  author = {Zhi Xuan Li and Wei Ma and Yi Jun Kong and Sin Neng Chio and Chang Li Zhang and Chi Tou Lei and She Xia Zhan},
  title = {Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water},
  journal = {American Journal of Environmental Protection},
  volume = {11},
  number = {2},
  pages = {32-38},
  doi = {10.11648/j.ajep.20221102.14},
  url = {https://doi.org/10.11648/j.ajep.20221102.14},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajep.20221102.14},
  abstract = {The evaluation of measurement uncertainty (MU) is an important method for quantitative determinations derived by microbial cultivation, thus it could further improve the result accuracy. In this study, we aimed to evaluate the MU in total bacteria counts (TBC) in water. Experiments were carried out using Pour Plate Method. The bottom-up approach was used to access the MU of TBC and different mathematical models were set up based on microbial growth principles and test process. Two geometric and five non-geometric progression factors derived from fishbone diagram were selected in these models, especially considering the influence of the bacteria binary fission. The results showed that the calculated value of expanded uncertainty was between 82 and 120CFU/mL when the test result was 100CFU/mL with the 95% confidence level. The geometric progression factor had a greater impact on MU evaluation with almost 80% of contribution, whilst non-geometric progression factor dedicated 60%. Experimental procedures such as sample repeatability, reproducibility and inoculation time should be drawn more attention, thus the accuracy of results could be improved. These innovative models not only reasonable and reliable, but also easy to use. The achievements of this study illustrated that the MU evaluation method could also be applied for analyzing other microbial indicators in water.},
 year = {2022}
}

Copy | Download

TY  - JOUR
T1  - Evaluation of Measurement Uncertainty from Pour Plate Method in Bacterial Enumeration in Water
AU  - Zhi Xuan Li
AU  - Wei Ma
AU  - Yi Jun Kong
AU  - Sin Neng Chio
AU  - Chang Li Zhang
AU  - Chi Tou Lei
AU  - She Xia Zhan
Y1  - 2022/04/25
PY  - 2022
N1  - https://doi.org/10.11648/j.ajep.20221102.14
DO  - 10.11648/j.ajep.20221102.14
T2  - American Journal of Environmental Protection
JF  - American Journal of Environmental Protection
JO  - American Journal of Environmental Protection
SP  - 32
EP  - 38
PB  - Science Publishing Group
SN  - 2328-5699
UR  - https://doi.org/10.11648/j.ajep.20221102.14
AB  - The evaluation of measurement uncertainty (MU) is an important method for quantitative determinations derived by microbial cultivation, thus it could further improve the result accuracy. In this study, we aimed to evaluate the MU in total bacteria counts (TBC) in water. Experiments were carried out using Pour Plate Method. The bottom-up approach was used to access the MU of TBC and different mathematical models were set up based on microbial growth principles and test process. Two geometric and five non-geometric progression factors derived from fishbone diagram were selected in these models, especially considering the influence of the bacteria binary fission. The results showed that the calculated value of expanded uncertainty was between 82 and 120CFU/mL when the test result was 100CFU/mL with the 95% confidence level. The geometric progression factor had a greater impact on MU evaluation with almost 80% of contribution, whilst non-geometric progression factor dedicated 60%. Experimental procedures such as sample repeatability, reproducibility and inoculation time should be drawn more attention, thus the accuracy of results could be improved. These innovative models not only reasonable and reliable, but also easy to use. The achievements of this study illustrated that the MU evaluation method could also be applied for analyzing other microbial indicators in water.
VL  - 11
IS  - 2
ER  -

Copy | Download