RESUMO
For understanding the mechanism of biodegradation in a SBR reactor treating nitrogen-containing aromatic wastewater, the reactor sludge samples were used for PCR-DGGE analysis. Meanwhile, 90 strains were isolated from the sludge sample after the start-up stage, 36 strains can degrade nitrogen-containing aromatic compounds. 5 strains nitrogen-containing aromatic degraders were further performed aromatic ring cleavage dioxygenase analysis. Result showed that bacterial diversity in the reactor were changed during the start-up stage, Acidobacteria (SBR1, SBR7), Actinobacteria (SBR4) and beta-Proteobacteria (SBR6) may play important role in biodegradation of nitrogen-containing aromatic compounds, among the isolates. Different bacterial diversity research method all have bias, and reflected different part of the bacterial structure. Among the isolates, Actinobacteria were the majority, by analysis the ring cleavage enzyme activity, further understood how the four nitrogen-containing aromatic compound were degraded in the reactor. The results provided valuable references for studying microbiological degradation mechanism in the reactor, and enriched microbial resources of nitrogen-containing aromatic degrader.