Co-Degradation of Ofloxacin and its Impact on Solid Phase Denitrification with Polycaprolactone as Carbon Source

Solid-phase denitrification has been applied for advanced nitrogen removal of wastewater, which also has the potential to co-degrade emerging pollutants. Fluoroquinolones (FQs) as a broad spectral antibiotic are frequently detected in effluent of conventional wastewater treatment plants. Yet it is still unclear whether solid-phase denitrifying bacteria could remove FQs. Thus, this study investigated the removal capacity of Ofloxacin (OFX) as representative of FQs and the microbial community structures of denitrifying sludge acclimated by polycaprolactone (PCL) and OFX. Results indicated that OFX had significant effect on the denitrification performance. OFX could be degraded, and a possible pathway was revealed based on UPLC-QTOF-MS. The dominant genera of acclimated denitrifying sludge belong to Microbacterium, Simplicispira, Alicycliphilus, Reyranella, Sediminibacterium, Acidovorax and Thermomonas. Moreover, ABC transporters and cytochrome P450, relating to multi-drug resistance and drug metabolism, were observed to be highly expressed in the acclimated sludge. This study provides novel insights into antibiotics control