| Abbreviations | 第4-5页 |
| Abstract | 第5-6页 |
| Chapter I Introduction | 第9-20页 |
| 1.0 Background | 第9-10页 |
| 1.1 Polycyclic aromatic hydrocarbons (PAHs) | 第10-11页 |
| 1.2 Aromatic hydrocarbons in the Environment-sources and fate | 第11-12页 |
| 1.3 Pathways and enzymes involved in PAHs degradation | 第12-13页 |
| 1.4 Microorganisms involved in PAHs degradation | 第13-14页 |
| 1.5 Microbial production of biosurfactant | 第14-15页 |
| 1.6 Principles of bioremediation | 第15-16页 |
| 1.7 Microbial metabolism of pollutants | 第16-18页 |
| 1.7.1 Variations on basic metabolism of pollutants | 第17-18页 |
| 1.7.2 Secondary utilization and Co-metabolism | 第18页 |
| 1.8 Incomplete degradation of contaminants | 第18-19页 |
| 1.8.1 Inability to Remove Contaminants to Low Concentrations | 第19页 |
| 1.9 Petroleum Hydrocarbons and Derivatives | 第19-20页 |
| Chapter II | 第20-26页 |
| 2.0 Materials and methods | 第20页 |
| 2.1 Chemicals and culture media | 第20页 |
| 2.2 Waste water sample | 第20-21页 |
| 2.3 PHE degradation experiments | 第21页 |
| 2.3.1. Bacterial strains and cultivation | 第21页 |
| 2.4 Isolation and identification of pure cultures | 第21-22页 |
| 2.5 Identification of bacterial species through molecular biology | 第22-24页 |
| 2.5.1 Extraction of Genetic DNA | 第22-23页 |
| 2.5.2 Gel Electrophoresis | 第23页 |
| 2.5.3 PCR amplification | 第23-24页 |
| 2.6 Determination of PHE degradation by individual bacterial isolates | 第24页 |
| 2.7 Low and High Molecular weight degradation by individual bacterial isolates | 第24页 |
| 2.8 Formation of catechol as intermediate for gene-encoding enzyme produced by individual bacterial isolates | 第24-25页 |
| 2.9 Experiments on biosurfactants | 第25-26页 |
| 2.9.1 Haemolytic activity of bacterial strains | 第25页 |
| 2.9.2 Emulsification measurement | 第25-26页 |
| Chapter III | 第26-38页 |
| 3.0 Results | 第26页 |
| 3.1. Biodegradation of Phenanthrene by bacterium consortia | 第26-29页 |
| 3.2. Isolates of pure bacterial colonies from three samples (HY, YY and WS) | 第29-31页 |
| 3.3. Taxonomic nomenclature of the six bacterial isolates | 第31-32页 |
| 3.4. Degradation of PHE by bacterial isolates | 第32页 |
| 3.5. Degradation of Low and High Molecular Weight hydrocarbons by bacterial isolates | 第32-33页 |
| 3.6. Catechol as an intermediate of the gene encoding enzyme-an enzyme degrading pollutants | 第33页 |
| 3.7. Screening of biosurfactant-producing bacterial isolates | 第33-38页 |
| Chapter IV | 第38-43页 |
| 4.0 Discussion and Conclusion | 第38页 |
| 4.1 Discussion | 第38-41页 |
| 4.2 Conclusion | 第41-43页 |
| References | 第43-47页 |
| Acknowledgements | 第47-49页 |
| Appendix | 第49-50页 |
