三环唑特效降解菌的筛选鉴定和表征_毕业论文

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三环唑特效降解菌的筛选鉴定和表征

摘要三环唑作为一种防治稻瘟病菌的农药,具有高生物毒性,光稳定性和热稳定性强,自然条件下半衰期很长。本实验筛选出一株新型三环唑降解菌NJUST37,并对其进行鉴定和表征,研究其生物降解的特性。该降解菌是目前已知的第一株以三环唑为唯一碳源,氮源和硫源的细菌。菌株降解三环唑最佳条件为温度30ºC、pH= 7。与此同时,本文还探究了外加碳源和氮源对特效菌降解作用的影响,结果表明:(1)三种不同浓度的酵母浸出液都对特效菌降解三环唑有极大促进作用,蔗糖和葡萄糖对特效菌的降解在起始阶段有促进作用,而后逐渐变为抑制作用,且抑制作用随着浓度的增高而加大;(2)大部分无机氮源的加入对三环唑降解有明显促进作用,而只有高浓度亚硝酸根离子(10mM/L)的加入完全抑制降解。此外,研究表明,NJUST37菌对100mg/L三环唑溶液的TOC和COD去除率均可达到60%左右。本实验通过测定三环唑的降解中间产物,提出了一条可能的三环唑生物降解机理。78504

毕业论文关键词    三环唑  特效菌  生物降解  降解路径

毕业设计说明书外文摘要

Title      Study on isolation, identification and characteristic of tricyclazole degreding strain

                                         

Abstract Tricyclazole, which is refractory, photostable and thermostable, is a kind of pesticide for preventing Pyricularia oryzae。 Tricyclazole has a long half life under nature conditions。 A new tricyclazole degrading strain is isolated, identified and characterized in the study。 The characterization of the strain and its incubation condition for degradation of tricyclazole are investigated in this paper。 The new strain is the first tricyclazole degrading strain which can utilize tricyclazole as the sole carbon, nitrogen and sulphur source。 The optimum incubation temperature and initial pH for tricyclazole degradation are 30℃and pH7, respectively。 At the same time, the influence of additional carbon and nitrogen source on tricyclazole degradation is investigated。 The results is as follows: (1)Tricyclazole degradation could be remarkably accelerated by the addition of Yeast extract。 The degradation of tricyclazole can be accelerated by additional glucose and sucrose at first, while inhibition is occured at later phase。(2)The degradation of tricyclazole is remarkably accelerated by additional inorganic nitrogen。 And the degradation is inhibited completely by high concentration of NO2-(10mM/L)。 Besides, the removal rate of TOC and COD is about 60% in solution which containing 100mg/L tricyclazole。 And a possible pathway of degradation is proposed in this study。 

Keywords  Tricyclazole  Specific bacteria  biodegradation  characterization

目   次

1  引言 1

1。1  三环唑简介 1

1。2  三环唑结构与性质 1

1。3  三环唑的应用 2

1。4  三环唑的危害 2

1。5  三环唑废水治理研究现状 2

1。6  课题研究目标及意义 5

材料与方法 6

2。1  实验材料 6

2。2  实验方法 7

3  结果与讨论 11 (责任编辑:qin)