Quantitative and Microbial Composition of Dehalococcoides sp. from Chloroethene-Contaminated Groundwater in Taiwan

• Main Authors: Kai-Ting Chang, 張凱婷
• Other Authors: 洪俊雄
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/w68gp6

碩士 === 國立中興大學 === 環境工程學系所 === 101 === Chlorinated solvents are widely used in dry cleaning processes, degreasing agent, semiconductor manufacture, and insecticides. Improper discharge of contaminants is likely to result in critical environmental damage. In year 2000, the Taiwanese government enforced the Soil and Groundwater Remediation Act, issuing detailed regulations on the prevention, control, and treatment of soil and groundwater. Bioremediation is commonly deemed as a cost-effective way in dealig with the issues of environmental remediation. Molecular biology is applied in this study to analyze the Dehalococcoides sp. that exists in the chlorinated solvents found in contaminated sites. Gene database is used in the pairwise of Dehalococoides sp. primaers, which can be applied to target the Dehalococcoides sp. at a specific site. It can also be used to estimate the species’s quantity. The analytical results are further processed with the use of PCR-DGGE and Real-time PCR to obtain the data with regard to the species’s population and quantity. The species can also be used to assess the degradation of chlorinated solvents at the sites. The study also monitored the co-culture between Dehalococcoides sp. and other microorganisms to discuss the biological interactions during the course of bioremediation. The growth of Dehalococcoides sp. serves the role of the benchmark on which the treatment is based. Samples from fourteen sites are chosen in the study for investigation. The microorganisms species found in different sites yielded different analytical results, despite the identical contaminants. The subclasses of Dehalococcoides sp., including strain ANAS2, 195, VS, and MB, were found in some sites in the middle region of Taiwan. Among the subclasses, strain 195 was also found at another untreated site in the same area, which indicates that with the existence of contaminants, substrate, and electron acceptors, Dehalococcoides sp. is likely to survive without any bioremediation. Other microorganisms that can coexist with Dehalococcoides sp. include Alcaligenes faecalis、Rubellimicrobium、Paracoccus alcaliphilus、Serratia marcescens、 Lactobacillus sp.、Lactobacillus farraginis、Olsenella sp.and Desulfovibrio sp.. The molecular biology methods established in the study is confirmed to be able to track down in-situ changes and enhance the effects of biological treatment.