好氧反硝化细菌的分离鉴定及其脱氮性能的初步研究

发布时间：2018-05-01 23:33

  本文选题：好氧反硝化菌 + 分离鉴定　； 参考：《福建农林大学》2015年硕士论文

【摘要】：氮素是是引起水质恶化,导致水体富营养化的罪魁祸首之一,逐渐成为严重的全球性环境问题,因而如何有效对其治理已引起越来越广泛的关注。目前,被公认为最经济、有效、也是最有发展前途的处理方法是生物法。然而,传统生物脱氮途经一般要分别经过好氧自养硝化和缺氧异养反硝化两个完全独立的过程,导致处理过程相对较复杂。随着好氧反硝化菌的发现,硝化反硝化过程可同时在同一反应器内进行,不仅可减少用地,还大大降低了处理成本。本文从福建农林大学的观音湖中(富营养期)取样,对其中的好氧反硝化菌进行分离及鉴定,同时初步研究了其脱氮性能,以其为在氮素污染治理中的应用提供数据支撑与理论指导。一方面,利用BTB平板的显色反应初行初筛,再经过摇瓶复筛后得到三株具有较高好氧反硝化活性的细菌,并分别命名为HJH1、HJH2和HJH3。随后,通过菌种的扩大培养、提取DNA、采用PCR扩增三菌株的16SrDNA并测序分析表明,菌株HJH1与Pseudomonas putida strain A5.5的16SrDNA序列相似性为94%,最有可能是假单胞菌属,并用MP法构建了系统进化树。菌株HJH2与Klebsiella oxytoca strain IARI-NIAW2-11同源相似性达98%,最有可能是克雷伯菌属,命名为Klebsiella oxytoca strain HJH2;通过16SrDNA基因序列测定菌株HJH3初步鉴定为分散泛菌属。另一方面,研究了菌株的好氧反硝化特性、耐受亚硝态氮浓度以及对于该菌株反硝化作用的最适pH、温度、碳源。结果表明,三株菌株可以有效去除亚硝态氮,菌株HJH1亚硝态氮最大耐受浓度为70mg/L,菌株HJH2亚硝态氮最大耐受浓度为80mg/L,菌株HJH3亚硝态氮最大耐受浓度为500mg/L；菌株HJH1、 HJH2生长的最适pH为7,菌株HJH3生长的最适pH为10；菌株HJH1、HJH2最适温度为30℃,菌株HJH3的最适合的温度为37℃；当碳源初始浓度为0.1mol/L时,甘油为最合适的碳源；菌株HJH1最适合的碳源为甘油,菌株HJH2最适合的碳源为甘油,菌株HJH3最适合的碳源为丁二酸钠。
[Abstract]:Nitrogen is one of the main culprits that cause the deterioration of water quality and eutrophication of water, and it has gradually become a serious global environmental problem. Therefore, more and more attention has been paid to the effective management of nitrogen. At present, it is recognized as the most economical, effective, and the most promising treatment method is biological law. However, the traditional biological denitrification process usually goes through two completely independent processes of aerobic autotrophic nitrification and anoxic heterotrophic denitrification, which leads to the relatively complex treatment process. With the discovery of aerobic denitrifying bacteria, the nitrification and denitrification process can be carried out in the same reactor at the same time, which can not only reduce the land use, but also greatly reduce the treatment cost. In this paper, the aerobic denitrifying bacteria were isolated and identified from Guanyin Lake (eutrophic period) of Fujian Agriculture and Forestry University, and their denitrification properties were preliminarily studied. It provides data support and theoretical guidance for the application of nitrogen pollution control. On the one hand, three strains of bacteria with high aerobic denitrification activity were obtained by the initial screening of BTB plate color reaction and then by shaking flask rescreening, and were named HJH1, HJH2 and HJH3, respectively. The 16SrDNA of the three strains was amplified by PCR and sequenced. The results showed that the similarity of 16SrDNA sequence between HJH1 and Pseudomonas putida strain A5.5 was 94g, the most likely was Pseudomonas, and the phylogenetic tree was constructed by MP method. The homology of HJH2 and Klebsiella oxytoca strain IARI-NIAW2-11 was 98%, and the most likely was Klebsiella, named Klebsiella oxytoca strain HJH2, and identified as panbacterium by 16SrDNA gene sequencing. On the other hand, the characteristics of aerobic denitrification, tolerance to nitrite nitrogen concentration and the optimum pH, temperature and carbon source for denitrification of the strain were studied. The results showed that three strains could effectively remove nitrite nitrogen. The maximum tolerance concentration of nitrite nitrogen in strain HJH1 was 70 mg / L, the maximum tolerance concentration of nitrite nitrogen in strain HJH2 was 80 mg / L, the maximum tolerance concentration of nitrite nitrogen in strain HJH3 was 500 mg / L, the optimum pH for the growth of HJH2 was 7, the optimum pH for growth of HJH3 was 10, the maximum tolerance concentration of nitrite nitrogen in strain HJH1 was 70 mg / L, that of strain HJH2 was 80 mg / L, and that of strain HJH3 was 500 mg / L. The optimum temperature of HJH1 and HJH2 is 30 鈩，

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