Assessment of the bacterial community for denitrifying removal of nitric oxide in a rotating drum biofilter by denaturing gradient gel electrophoresis.

Abstract The emission of nitric oxide (NO) to the atmosphere is a major environmental problem. To abate NO emission from the industrial flue gas, a rotating drum biofilter (RDB) was developed for the denitrifying removal of NO. After the start-up period, the RDB could effectively remove NO from the waste gas and the denitrifying removal efficiency could reach 85%. After the addition of CuII(EDTA) to the nutrients, the removal efficiency could increase to 99.1%. To improve the understanding of the relationship between the composition of bacterial population and the performance of the RDB, a denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction-amplified genes coding for 16S rRNA was used to analyze and determine the changes in bacterial communities in the RDB. Results showed that there was a slight change in microbial diversity after the addition of CuII(EDTA) to the nutrient solution, which led to an increase in NO removal efficiency. Eight major bands of 16S rRNA gene fragments obta...