Cometabolic Degradation of Anti-Inflammatory and Analgesic Pharmaceuticals by a Pentane Enrichment Culture

Pharmaceutically active compounds (PhACs) are common contaminants found in surface and groundwaters, often due to their inefficient removal from wastewater treatment plants. One way in which these compounds can be removed is via aerobic cometabolism, a process that involves oxygenases produced by microorganisms. Limited work has been done examining the efficacy of cometabolism in the removal of PhACs. Therefore, the aim of this work was to investigate the use of an alkane (pentane) in the aerobic cometabolic transformations of paracetamol, ibuprofen, naproxen, diclofenac, and nimesulide. Both paracetamol and ibuprofen (single aromatic compounds) were readily transformed, with net specific biodegradation rates equal to 1.6 and 3.2 μmol/gcell/day, respectively. Conversely, the two aromatic ring PhACs showed slower (naproxen and nimesulide) or no transformation (diclofenac). In addition, four of the tested PhACs (ibuprofen, paracetamol, naproxen and nimesulide) did not inhibit pentane uptake