中文摘要：

对分离筛选到1株能以二氯甲烷（DCM）为唯一碳源和能源生长的菌株Methylobacterium rhodesianum H13进行降解特性研究.在初始菌体浓度0.82 mg.L-1、pH 7.0和温度30℃的条件下,M.rhodesianum H13能够于23 h内将5 mmol.L-1DCM完全降解,细胞得率（细胞/DCM）为0.136 g.g-1.随着DCM的降解,溶液中的Cl-浓度逐渐升高（释放的Cl-浓度约为DCM的2倍）,溶液pH值降至6.75,呈弱酸性.通过摇瓶实验考察了温度、pH、DCM浓度、Cl-等因素对菌株H13降解DCM性能的影响,获得其较适宜的生长和降解条件为：温度30℃、pH值7.0.研究还发现M.rhodesianum H13降解DCM的最适浓度为5 mmol.L-1,高浓度的DCM会抑制其降解.研究成果对高效处理环境中的DCM污染具有重要的应用价值.

英文摘要：

A dichloromethane-degrading bacterium Methylobacterium rhodesianum H13 which utilized the DCM as the sole carbon and energy source was isolated.According to the research,M.rhodesianum H13 could completely degrade 5 mmol.L-1 DCM in 23 h with the initial cell concentration of 0.82 mg.L-1,pH 7.0,30℃,and the cell yield rate was about 0.136 g.g-1 DCM.With the degradation of DCM,Cl-concentration gradually raised（the release of Cl-concentration was about 2 times higher as the DCM）,pH value dropped to 6.75,and the solution was weakly acidic.Temperature,pH,DCM concentration,Cl-concentration and other factors were investigated through the shake flask experiments,and the optimal conditions for DCM degradation were： temperature 30℃,pH 7.0.The study also indicated that 5 mmol.L-1 of DCM was the optimum concentration for M.rhodesianum H13 and high levels of DCM could inhibit the degradation.The research has an important application value for the DCM environmental pollution.