Degradation of quinoline and indole co-substrate under anaerobic denitrification and methanogenesis conditions

Bath experimrnts were conducted to study the degradation characteristics and microbial community of quinoline and indoles co-substrate under anaerobic denitrification and methanogenesis conditions, which were known as typical N-heterocyclic compounds. The results showed that the presence of quinolone could inhibit the degradation of indole, and the inhibition effect was enhanced with the increase of quinoline concentration; the presence of indole could promote the degradation of quinoline, but the high concentration of indole (150mg/L) inhibited the degradation of quinolone; the kinetics of quinoline and indole was followed the zero-order kinetics model; through GC-MS analyses, the intermediate metabolites of quinoline were 2-hydroxyquinoline and 2,8-dihydroxyquinoline; and metabolites of indole were oxindole and isatin. The high-throughput sequencing technology was used to analyze the microbial community structure, and results indicated that the functional bacterial were enriched in the anaerobic denitrification and methanogenesis system. The bacterial phylum was Proteobacteria, the dominant classes were Gammaproteobacteria and Betaproteobacteria, and the dominant genera were Acinetobacter, Candidimonas, Azospira, and Desulfomicrobium. © 2019, Editorial Board of China Environmental Science. All right reserved.