Bacterial Consortium in the Biodegradation of Polycyclic Aromatic Hydrocarbons-Phenanthrene

作     者：John Farmer 

作者单位：东北师范大学 

学位级别：硕士

导师姓名：Xingzhi Wang

授予年度：2010年

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 07[理学] 08[工学] 09[农学] 0903[农学-农业资源与环境] 0713[理学-生态学] 

主      题：biodegradation Phenanthrene waste water pH Optical Density (OD) pure clones Genetic DNA biosurfactant emulsion clear zones 

摘      要：Many aromatic hydrocarbons are known to be toxic and carcinogenic to humans and their contamination of soils and water bodies is of great environmental concern. Hence microbial degradation of these hydrocarbons to less toxic compounds has become a vital tool in making the environment safe for humans as well as other life forms. In this study, industrial waste water samples were randomly collected from three different locations in Shuangyang local brewery. These samples were designated by the letters: HY, YY and WS. The waste water samples were used to isolate bacterium species using LB liquid medium. These bacterium cultures were transferred to a fresh media containing a concentration of Phenanthrene. The pH and Optical Density (OD) readings were measured and recorded on daily basis for a period of one week and this was the first transfer. This was done in other to ascertain the biodegradation capability of the bacterium strains in the Phenanthrene medium and the pH at which these strains degrade the pollutant- Phenanthrene. However, this process was repeated for another four consecutive weeks (five transfers). Meanwhile, from the fifth transfer the aliquot culture MSM-PHE medium was again transferred to a fresh liquid LB media and allowed to grow overnight. The bacterial cultures were again transferred to a solid MSM agar medium to obtain single colonies of bacterial strains. These cultures were transferred to a liquid MSM medium for 24 hrs and transferred again to the solid medium. This process was repeated for another three weeks to isolate pure clones. Pure clones were isolated with distinct colors and morphologies. The genetic DNA of these pure colonies was extracted, purified and two primers were used for the PCR analysis and the isolates were identified by blast analysis. These single isolates were later inoculated in a liquid MSM-PHE culture medium and their densities (biomass) were measured and recorded for a week. The isolates were also inoculated on