Response of Azotobacter beijerinckii C4 to oxidative stress of Cd~(2+),acetochlor and their association

The activity response of the antioxidant enzymes of Azotobacter beijerinckii C4(G~-) following exposure to Cd~(2+),acetochlor and their associations was investigated.Results showed that activities of SOD,CAT and ATPase in the bacterium were induced positively and obviously by Cd~(2+) or acetochlor,especially at the beginning time after treatment.The associated pollution of Cd~(2+) and acetochlor had different impacts on the activity of the antioxidant enzymes with different concentrations and treatment time.SOD and ATPase activities by the associations appeared stronger than each of their single factor,and the activities were consistent with each of their single factor finally.It presented induced or inhibited actions on CAT activity by various concentration associations,and appeared inhibiting effect ultimately.