2023 Volume 79 Issue 25 Article ID: 23-25032
In this study, in order to control and reduce nitrous oxide (N2O) production by nitrifying bacteria, we focused on NO which is a precursor of N2O in nitrifier denitrification by Ammonia oxidizing bacteria (AOB) and a substance used by AOB in energy acquisition. We conducted an experimental validation to clarify the interrelationship between NO and N2O emission characteristics of nitrifying bacteria cultivated on artificial substrates. The results showed that temporal changes in NO production by nitrifying bacteria precede temporal changes in N2O production. Furthermore, abundant NO supply to AOB, indicated increases the rate of ammonia oxidation and decreases the conversion ratio to N2O from oxidized ammonia. Using NO as an engineering indicator, it may be possible to comprehensively predict and control N2O production and nitrification activity of nitrifying bacteria.
