Abstract—This study explores the role of Comammox
Nitrospira (CMX) in ammonia-nitrogen removal from synthetic
municipal wastewater, with a focus on key operational
parameters: initial ammonia concentration (N₀), COD/N ratio,
and pH. A Full Factorial Design (FFD) of Experiments was
implemented to systematically evaluate the effects of these
factors on nitrification efficiency. Microbial population
dynamics were assessed using DNA and rRNA qPCR analyses,
providing insights into the relative abundance and activity of
CMX in comparison to Ammonia Oxidizing Bacteria (AOB).
The experimental results suggest that CMX plays a dominant
role in ammonia oxidation, as indicated by minimal nitrite
accumulation across all conditions. The optimal experimental
condition (N₀ = 60 mg/L, COD/N = 0.5, pH = 8.6) was identified
through a prediction profiler function. Statistical modeling
confirmed that ammonia removal was significantly influenced
by the tested parameters (p = 0.0124, F-ratio = 3797.377),
whereas nitrate formation exhibited less variation and was not
statistically significant (p = 0.4121, F-ratio = 3.0531). These
findings contribute to a deeper understanding of complete
ammonia oxidation and its implications for optimizing
biological nitrogen removal in wastewater treatment systems.
Keywords—Comammox Nitrospira, nitrification, biological
nitrogen removal, ammonia oxidation, Full Factorial Design,
microbial population dynamics, qPCR analysis
Cite: Tristan Roy L. Panaligan, Yi-Ju Wu, Bonifacio T. Doma, Jr., and Liang-Ming Whang, "Correlation Analysis of COMAMMOX Nitrospira Relative to AOB Activity in Biological Nitrogen Removal from Synthetic Municipal Wastewater Using Full Factorial Design," International Journal of Environmental Science and Development vol. 16, no. 4, pp. 243-252, 2025.
Copyright © 2025 by the authors. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).