四氯乙烯污染对小麦幼苗抗氧化酶系的影响

Effects on the antioxidant enzymes in wheat seedlings subjected to tetrachloroethylene

通过室内模拟试验,采用愈创木酚法、高锰酸钾滴定法、氮蓝四唑法分别测定了四氯乙烯(PCE)污染小麦幼苗的过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物岐化酶(SOD)等抗氧化物酶系,研究了PCE污染对植物生物学指标的影响,以评价土壤PCE污染的生态毒性效应,为土壤性质的变化趋势提供依据。结果表明,PCE浓度较低时,POD、SOD活性被激活,表现出明显的抗氧化能力,但PCE浓度过高时则抑制POD和SOD的活性诱导作用;小麦幼苗中CAT活性只有在PCE为0.10mg/kg时被激活,其他浓度时CAT活性均受到抑制;随着时间的延长,POD、CAT的活性均呈激活态势,而SOD活性在PCE浓度较低时呈降低趋势,在PCE浓度较高时,SOD活性升高。

Guaiacol, potassium permanganate titration and NBT-law were used to determine peroxidase（POD）, catalase（CAT）, superoxide dismutase（SOD） of wheat seedlings in soil polluted by PCE to evaluate effects of ecotoxicity and the amounts of microorganism in soil polluted by PCE and to provide a basis for changes of the soil nature. The results showed that, POD and SOD were activitied by lower pollution concentrations, and demonstrate significant antioxidant capacities, but induction was inhibited by higher concentration. CAT was activatied only when PCE was 0.10 mg/kg, and CAT was decreasing at other PCE concentrations. POD and CAT were all activitied with time, but SOD was decreasing at lower degree and increasing at higher degree.