Effect of photodegradated quinoline aqueous solutions on enzyme activities in activated sludge

Synthesized wastewater containing quinoline photocatalytic oxidized at 0, 30 and 60 min respectively were applied in flask cultivation of activated sludge to evaluate the changes of activities of dehydrogenase, protease and urease in activated sludge with reference is glucose. The experiment results showed that quinoline aqueous solution after photodegradation of 60 min appeared to inconspicuous influence on the activities of dehydrogenase and protease, while after photodegradation of 0 min or 30 min the effluents presented obviously inhabitation. However, the urease activity cultured in all photodegradated quinoline solutions was higher than that in glucose medium due to the effect of C-N bond induction. Under the tested conditions, the optimal pretreatment time of photocatalysis system was observed at 60 minutes, which suggested that enzyme activity in activated sludge was benefited to investigate the biodegradability of wastewater for evaluating the optimal reaction time for photocatalytic pretreatment system.