Industrial wastes often contain a mixture of recalcitrant compounds as well as easily biodegradable compounds. Investigation of biodegradation of recalcitrant pollutants in the presence of nontoxic, easily biodegradable organic compounds is a real topic for waste treatment engineers and scientists. In this paper, the kinetics of co-metabolism of quinoline and glucose by Burkholderia pickettii, a quinoline-degrading bacterium isolated from acclimated activated sludge, was studied. The experimental results demonstrated that both quinoline and glucose could be degraded simultaneously. The results also showed that the biodegradation rate of quinoline was accelerated by the presence of glucose, while glucose degradation was inhibited by the presence of quinoline. At relatively low concentration of quinoline (50 mg l(-1)) and glucose (34, 60, 110 mg l(-1)), biodegradation kinetics of both quinoline and glucose could be described by first-order reaction kinetics model. It was also found that at higher substrates concentrations (quinoline 300 mg l(-1); glucose 110, 320, 690 mg l(-1)), quinoline biodegradation did not follow either first- or zero-order reaction kinetics model. When glucose concentration was 110 mg l(-1), its degradation followed the first-order reaction kinetics model, however with the increase of glucose concentrations to 320 and 690 mg l(-1), the biodegradation of glucose followed the zero-order reaction kinetics equation. (C) 2002 Elsevier Science Ltd. All rights reserved.