| Summary: | 碩士 === 東吳大學 === 微生物學系 === 104 === With huge advances in chemical technology in passed decades, human life becomes more convenient. On the other hand, the problems of environment pollution become more serious due to some of harmful chemicals had been disposed. Most of the rivers in Taiwan are suffering the pollution of bromine compounds. The bromine compounds are major materials used for flame retardants in furnitures, electronic products, etc.. They are also major parts of the persistent organic pollutants of our environment. The purpose of this study is to remove three major bromine compounds; decabromodiphenyl ether (BDE-209), tetrabromobisphenol A (TBBPA) and dibromo diphenyl ether (BDE-15) by biogradation , and to identify the difference of bacterial community between the sediments of Tamsui river from Guandu (關渡) and Bali(八里).
The results indicated sediment with zero valent iron exhibit enhanced debromination of BDE-209 and TBBPA in anaerobic conditims. Moreover, both TBBPA and BDE-15 degradation in aerobic sediments with enzyme extract were enhanced. The reductive intermediate products resulting from the debromination of BDE-209 were nona-BDE (BDE-206, 207), octa-BDEs (BDE-196, 197), hepta-BDEs (BDE-183, 184, 191), hexa-BDEs (BDE-138,153 , 154, 156), penta-BDEs (BDE-85, 99, 100, 119, 126), tetra-BDEs (BDE-47, 49, 66, 77), tri-BDEs (BDE-17, 28), di-BDEs (BDE15) .
Analysis pyrosequencing results and degradation curves revealed that the BDE-209 can be degraded by bacterial genera Actibacter and Paracasoccus. TBBPA can be degraded by bacterial genera Anaeromyxobacter, Altererythrobacter, Parvularcula, Methylobacterium, Phycisphaera, Pelagibius, Gp23, Methylobacillus and Sulfurimonas. The BDE-15 can be degraded Bacillus sp., Lysinibacillus sp., Rhodococcus aetherivorans,
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Lysobacter sp and Micrococcus yunnanensis. Especially, Lysinibacillus sp. can degrade 70% BDE-15 within two weeks.
Our results suggest that bromine compounds can be biodegraded by bacterialstrains mentioned above that isolated from sediment in river of Tamsui as well as bacterial communities are different in terms of locations and seasons.
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