Analysis of nitrifying bacteria growth on two new types of biomass carrier using respirometry and molecular genetic methods

• Published in: Ecotoxicology and environmental safety 2021-12, Vol.225, p.112795-112795, Article 112795
• Main Authors: Havlíček, Karel, Nechanická, Magda, Lederer, Tomáš, Kolčavová Sirková, Brigita
• Format: Article
• Language: English
• Subjects: Biofilm; Biomass carriers; Molecular genetic methods; Nitrification; Nitrifying bacteria; Respirometry
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2021.112795

This work addresses the testing of two newly produced biomass carriers (micro- and nanofibers) and one commercially available AnoxKaldnes™ K3 carrier in a laboratory post-nitrification reactor. The carriers were prepared under parameters suitable for high-quality biomass adhesion to their surface, and each was characterized by its specific structures. As part of the evaluation of the biofilms using respirometry and molecular genetic methods, the carriers were assessed in terms of their effectiveness and comparability. The rate of biofilm development was dependent on the structure and surface properties of the individual carriers. The results showed that the biofilm most strongly adhered to nanofiber carriers, where nitrating bacteria's slower but more abundant development occurred. Microfiber carriers were more stable, but a diverse internal structure may be unsuitable in a populated carrier's early stages. The AnoxKaldnes™ K3 carriers showed the slowest growth of biofilm, but the monitored nitrifying bacteria were abundant after an extended time. AOB representatives are likely to prefer an environment with a high amount of biomass and a large active area. Conversely, NOB representatives thrive better in a slowly forming biofilm. The methods used to monitor biofilm are challenging to compare directly, but they do complement each other, which aids in verifying the individual test results. Developing new types of biomass carriers with the potential for high-quality adhesion of microorganisms is a prerequisite for the expansion of highly efficient biotechnological processes, especially for wastewater treatment. [Display omitted] •Biofilm formation on newly developed micro- and nanofiber biomass carriers•High ammonia nitrogen removal efficiency from the simulated post-nitrification system•Very tightly bound biofilm on nanofiber carriers•Zoogloea bacteria as an indicator of biofilm formation•Assessment of biofilm on carriers using a combination of various modern methods