Biodegradation of ketoprofen using a microalgal-bacterial consortium

To test the toxicity of ketoprofen (a commonly-used NSAIDs) using two microalgal strains and Artemia sp. following the isolation of bacterial and microalgal strains and testing their ability to biodegrade and tolerate ketoprofen. Chlorella sp. was the most resistant to ketoprofen. A defined bacterial consortium (K-2) degraded 5 mM ketoprofen as a sole carbon source both in the dark or continuous illumination. Ketoprofen did not undergo photodegradation. In the dark, biodegradation was faster with a lag phase of 10 h, 41% COD removal and 82 % reduction in toxicity. The consortium degraded up to 16 mM ketoprofen. The consortium was composed of four bacterial isolates that were identified. MS/MS analysis suggested a ketoprofen biodegradation pathway that has not been previously reported. Combining Chlorella sp. and the K-2 consortium, ketoprofen was degraded within 7 days under a diurnal cycle of 12 h light/12 h dark. The feasibility of using a microalgal-bacterial system to treat pharmaceutical wastewater is promising for the reduction of the process cost and providing a safer technology for pharmaceutical wastewater treatment.