摘    要二氯甲烷（DCM）是使用和排放量大的氯代有机化合物（COCs）之一，具有较强的生物累积毒性，对生物安全性构成威胁，被认为是COCs污染中毒性较大的氯代有机物，环境中DCM超过10 mg/L浓度时即可对人体生理过程造成不同程度的干扰，具有“三致”效应，且已成为全球性问题。DCM的毒性主要是源于其氯元素的引入，若将DCM中的氯离子脱除，可显著降低其生物毒性，有利于后续的生物法彻底处理或作为能源进行回收利用。本文旨在通过对二氯甲烷脱氯重组菌的培养和产酶诱导表达，进而将获得的脱氯酶进行提取纯化，纯酶液进行二氯甲烷脱氯实验，通过离子色谱测定各时间段的水样中Cl-浓度变化验证脱氯效果。结果显示，实验组水样Cl-浓度平均值在3h内呈上升趋势，最高达到0。125mM；3-10h取样时间内维持在0。12mM左右达到平衡。对照组水样Cl-浓度在1。5h内上升，最高达到0。016mM；在1。5-10h取样时间内下降后维持在0。01mM左右达到平衡。该结果说明，二氯甲烷脱氯酶确实可以将DCM中的氯离子脱除，降低其生物毒性，但脱除效果在3h后达到饱和。3h以后，即使随着反应时间的增加，水样中的Cl-浓度也不再发生明显变化。综上所述，二氯甲烷脱氯酶确实可以将二氯甲烷中的氯离子脱除，从而降低其生物毒性。89766

毕业论文关键词：二氯甲烷；产酶诱导；粗酶提纯；脱氯

Abstract Dichloromethane (DCM) is one of the widely used chlorinated organic compounds (COCs) with strong bioaccumulative toxicity and poses a threat to biosafety。 It is considered to be a highly toxic chlorinated organism                              in COCs pollution Organic matter。 When the concentration of DCM exceeds 10 mg / L in the environment, it can cause different degrees of interference to human physiological processes and has "three" effect, and has become a global problem。 The toxicity of DCM is mainly due to the introduction of its chlorine element。 If the chloride chloride in DCM can be removal, its biological toxicity can significantly be reduced and is conducive to the subsequent biological treatment or as a source of energy for recycling。 The aim of this paper was to culture the dichloromethane dechlorination recombinant bacteria and Induce enzyme production, then the obtained dechlorination enzyme was subjected to extraction and purification。 The pure enzyme solution was subjected to dichloromethane dechlorination test。 The dechlorination effect was verified by ion chromatographic determination of Cl-concentration in the water samples of each time period。 The results showed that the average concentration of Cl-concentration in the experimental group increased within in the first 3h, reaching a maximum of 0。125mM, and maintain the balance about 0。12mM in the 3-10h。 The concentration of Cl-concentration in the control group increased within 1。5h, reaching a maximum of 0。016mM。 After that, in the 1。5-10h sampling time, the concentration of Cl-concentration declined to 0。01mM to maintain balance。 The results of this experiment described that dichloromethane dechlorination can indeed remove chloride ions from DCM and reduce its biotoxicity。 But the removal effect reached saturation after 3h。 After 3h, the concentration of Cl- in the water sample will no longer change significantly as the reaction time increases。 In summary, dichloromethane dechlorination can indeed remove the chloride ions from DCM and reduce its biological toxicity。

Keyword: Dichloromethane; enzyme induction; crude enzyme purification; dechlorination 

目    录

摘    要 1

Abstract