Research Article

Assessing the resilience of anammox bacteria to low-temperature stress in the presence of titanium dioxide nanoparticles

Number: 35 August 1, 2026

Assessing the resilience of anammox bacteria to low-temperature stress in the presence of titanium dioxide nanoparticles

Abstract

The objective of this study was to investigate the long-term effects of titanium dioxide (TiO2) nanoparticles (NPs) on the anammox process under low-temperature stress. In this context, two identical anammox bioreactors were subjected to varying temperatures starting from 35 °C and gradually decreased to 15 °C. The enrichment and test periods were completed in 210 days. The addition of TiO2 NPs enhanced nitrogen removal efficiency at the optimal temperature of 35 °C, increasing ammonium and nitrite removal efficiencies from 95.8 ± 1.2% to 97.2 ± 1.0% and from 94.2 ± 1.6% to 98.7 ± 0.5%, respectively. Moreover, TiO2 NPs addition significantly improved reactor performance under sub-optimal temperature conditions and provided stable operation at 25 °C with removal efficiencies of 86.5 ± 1.8% for ammonium and 92.3 ± 2.2% for nitrite. Since anammox systems are typically operated at temperatures around 30–35 °C to maintain high microbial activity, considerable heating energy is required in full-scale wastewater treatment plants. Therefore, the ability to sustain high treatment performance at lower temperatures provides a major operational advantage. As a result, the TiO2-modified anammox system reduced heating energy demand by 43.5% and demonstrated a cost-effective and sustainable strategy for improving nitrogen removal performance in wastewater treatment applications.

Keywords

Supporting Institution

This work was supported by the Scientific and Technological Research Council of Turkey [TUBITAK- Project No: 117Y214]; and Marmara University Scientific Research Committee [Project No: FEN-C-YLP-121218-0622].

Project Number

TUBITAK- Project No: 117Y214, Project No: FEN-C-YLP-121218-0622

References

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Details

Primary Language

English

Subjects

Nanobiotechnology, Bacteriology

Journal Section

Research Article

Publication Date

August 1, 2026

Submission Date

April 14, 2026

Acceptance Date

June 22, 2026

Published in Issue

Year 2026 Number: 35

APA
Akgül, D. (2026). Assessing the resilience of anammox bacteria to low-temperature stress in the presence of titanium dioxide nanoparticles. Biotech Studies, 35, 2008923. https://doi.org/10.38042/biotechstudies.2008923
AMA
1.Akgül D. Assessing the resilience of anammox bacteria to low-temperature stress in the presence of titanium dioxide nanoparticles. Biotech Studies. 2026;(35):2008923. doi:10.38042/biotechstudies.2008923
Chicago
Akgül, Deniz. 2026. “Assessing the Resilience of Anammox Bacteria to Low-Temperature Stress in the Presence of Titanium Dioxide Nanoparticles”. Biotech Studies, nos. 35: 2008923. https://doi.org/10.38042/biotechstudies.2008923.
EndNote
Akgül D (August 1, 2026) Assessing the resilience of anammox bacteria to low-temperature stress in the presence of titanium dioxide nanoparticles. Biotech Studies 35 2008923.
IEEE
[1]D. Akgül, “Assessing the resilience of anammox bacteria to low-temperature stress in the presence of titanium dioxide nanoparticles”, Biotech Studies, no. 35, p. 2008923, Aug. 2026, doi: 10.38042/biotechstudies.2008923.
ISNAD
Akgül, Deniz. “Assessing the Resilience of Anammox Bacteria to Low-Temperature Stress in the Presence of Titanium Dioxide Nanoparticles”. Biotech Studies. 35 (August 1, 2026): 2008923. https://doi.org/10.38042/biotechstudies.2008923.
JAMA
1.Akgül D. Assessing the resilience of anammox bacteria to low-temperature stress in the presence of titanium dioxide nanoparticles. Biotech Studies. 2026;:2008923.
MLA
Akgül, Deniz. “Assessing the Resilience of Anammox Bacteria to Low-Temperature Stress in the Presence of Titanium Dioxide Nanoparticles”. Biotech Studies, no. 35, Aug. 2026, p. 2008923, doi:10.38042/biotechstudies.2008923.
Vancouver
1.Deniz Akgül. Assessing the resilience of anammox bacteria to low-temperature stress in the presence of titanium dioxide nanoparticles. Biotech Studies. 2026 Aug. 1;(35):2008923. doi:10.38042/biotechstudies.2008923


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