| Using the indoor simulating method of dynamic and static exposure respectively,the toxic effects of TBBPA on the antioxidant enzyme defense systems and Glutathione-S-transferase(GST) activity of tubifex Monopylephorus limosus were examined.The activity of superoxide dismutase (SOD) and catalase (CAT) with time was also examined.The results showed that after an 8 d exposure,the SOD activity was enhanced at first and then inhibited gradually,at last enhanced again.The highest activity of SOD (p<0.01) was examined under 0.05mg/L concentration of TBBPA.And the activity of SOD was much higher than that of control (1.5-7.8 times more than that of the control).The activity of CAT showed a tendency of induction firstly and then inhibition,then induction again and at last inhibition,reached the highest value under 0.5 mg/L of TBBPA.Furthermore,the CAT activity was higher than that of the control (1.1-1.9 times more than that of the control) except that under 0.005 mg/L and 0.25 mg/L of TBBPA.Moreover,the highest activity of GST (p<0.01) was observed under 0.25 mg/L of TBBPA.The activity of GST was enhanced gradually at first and then inhibited.As the same as SOD,the activity of GST was induced significantly (p<0.05).The changes in the SOD activity showed an “M" trend,while that in the CAT activity showed an “N" trend.And the activity of SOD is steadier than that of CAT.Thus,changes in the activity of SOD and GST,especially SOD,can better reflect the toxic effects of pollutants on tubifex. |
