Diuron degradation by a mixed culture of bacteria immobilized in rice straw

Abstract

Diuron has been widely applied to control weeds causing serious environmental pollution. In the current study, the mixed culture of three bacterial isolates, Bacillus subtilis DU1, Acinetobacter baumannii DU, and Pseudomonas sp. DUK, was investigated for diuron degradation in a packed reactor and soil. The immobilization of the bacteria mixture in rice straw increased the degradation. The specific degradation rates of diuron by bacteria immobilized in rice straw in batch cultures increased from 0.38 ± 0.03 mg/L at the first cycle to 0.98 ± 0.10 mg/L at the fourth cycle. The degradation using the reactor was also carried out in a continuous operation. Moreover, the introduction of bacteria into soil increased diuron degradation. This study shows the potential of diuron degradation in the reactor and in soil using the mixed bacterial culture immobilized in rice straw.