固定化酶修复阿特拉津污染土壤效果及土壤细菌多样性动态变化分析

Effect of atrazine-contaminated soil by immobilization enzyme and dynamic variation of soil microbial

采用固定化处理和游离态降解酶修复阿特拉津污染土壤,在考查修复效果基础上,研究分析修复过程中其对土壤细菌多样性影响情况,评价固定化酶修复方法的可行性及其生态安全性。按1%(V/W)和5%(V/W)的投加量分别将固定化酶和游离酶施入阿特拉津浓度为100 mg·kg-1土壤中,于投加后第7、14、21和28天取样,测定阿特拉津降解。结果表明,投加量为1%(V/W)和5%(V/W)的游离酶降解率分别为32.38%和39.37%;而投加量为1%(V/W)和5%(V/W)的固定化酶降解率分别为72.84%和79.22%。在上述过程中采用PCR-DGGE技术研究不同处理土壤细菌群落组成的变化情况。结果显示,在整个修复过程中,添加游离酶、固定化酶及污染处理土壤中的微生物图谱所显示的优势种属几乎没有变化,各处理样品细菌多样性组成没有显著差异。结合固定化酶对土壤中阿特拉津的去除效果,说明所采用修复方法具有较好的生态安全性。

In order to evaluate the available and safety of immobilized enzyme, the immobilized and free enzyme was applied on bioremediaUon of atrazine-contaminate soil, based on the removal concentration, and the dynamic changes of soil microbial in contamination soil. The concentration of immobilized and free enzyme were all in 1% and 5% fertilized into the atrazine contaminated soil with the atrazine Content of 100 mg. kg1. After 7th, 14th, 21th, and 28th sampling, calculating the atrazine degradation. The results showed that the degradation rate of 1% （V/W）, and 5% （V/W） of the free enzyme and immobilized enzyme were 32.38%, 39.37%, 72.84% and 79.22%, respectively. Dynamicchanges of bacterial communities of different treatments were obtained by PCR-DGGE technology. The results as following in the remediation, the dominate species of microorganisms almost no change, and each sample had no significant difference in bacterial diversity under free enzyme and immobilized enzyme. The conclusion was that immobilized enzyme had the ability of degrading atrazine with high level, and put no effects on ecological safety.