【作者】 房苗苗；

【导师】 张秀霞；

【作者基本信息】 中国石油大学 ， 环境工程， 2007， 硕士

【摘要】 本文以筛选含氮杂环化合物高效降解菌并应用于石油污染土壤的生物修复为目标,进行了含氮杂环化合物吡啶、喹啉降解菌的筛选实验,对所筛高效降解菌进行环境优化实验,自然富集培养物的驯化和人工构建混合菌群,利用固定化技术构建微生物反应器,最终将微生物反应器应用于石油污染土壤的生物修复实验。通过大量实验,最终筛选出4株吡啶和喹啉高效降解菌,进行了形态特征、生理生化特征和DNA鉴定。对影响菌株生长和降解的主要因素,如pH值、温度、转速、接种量、碳氮源利用性、底物浓度等进行单因素、正交实验考察。自然富集菌群对吡啶和喹啉的降解效果和单菌株相当,且驯化时间短,操作更为简单。人工构建的优势菌群结构简单,降解效果不理想。采用固定化技术强化菌株降解效果和提高菌株对环境的适应性。对所选载体材料,及相应的包埋剂、交联剂种类浓度、pH值和交联时间等因素进行考察,以构建微生物反应器。实验证明,微生物反应器对环境条件有较宽适应性和较强降解能力;其反应速率和降解率远优于未固定菌株;对于高浓度底物,仍表现出理想的降解效果,且重复使用效果稳定。应用微生物反应器进行东营石油污染土壤生物修复模拟试验,20d吡啶降解完全,40d喹啉降解96.5%,效果理想。更多还原

【Abstract】 In order to screening strains with high biodegradation efficiency of nitrogenous heterocylic compounds and applying strains to oil contaminated soil, optimizing the conditions of stains, construction mix culture and domesticating strains, utilizing immobilization technology for bioreactor were investigated in this thesis.Quinoline and pyridine degrading bacterias were isolated by enrichment from 45 soil samples from various areas of China, especially polluted site by petroleum. Four high efficiency strains were selected for the biodegradation study. An alignment of the DNA sequences of the 16S rRNA gene of the bacterium with DNA sequences, available in GenBank database indicates that strain 2-13 is closest designated as Flexibacter giganteus, strain 4-11 is designated as Thiobacillus intermedius, strain Q5 is designated as Lactobacillus fermentum, strain Q24 is designated as Arthrobacter flavescens. The primary conditions were reviewed, such as pH value, temperature, rotation speed, inoculum size, carbon and nitrogen sources, the concentration of target etc.The initial mix culture after domesticated had excellent degradation as single strains, but shorter domestication period and easy manipulation. Artificial constructed mixed strains don’t have ideal effect, only 43.2%~57.1%.After immobilizing, the strains capacity of degradation was extremely enhanced. Compared with the untreated, the immobilized strains have a wide range on pH value and temperature, and higher degradability. At initial concentration 1500mg?L-1 of quinoline, the degrading rate in the bioreactor Q5 in 70 hours treatment coulde reach to 86.5%, and had steady effect.Bioreactor Q5 were appled to biodegradate oil contaminated soil in Shengli Oilfield, pyridine was biodegradated completely after 20ds, and the degradation rate of quinoline reach to 96.5% after 40d.更多还原