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.
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.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2013年第9期3613-3619,共7页
Environmental Science
基金
国家高技术研究发展计划(863)项目(2012AA063102)
国家自然科学基金项目(51178430)
浙江省创新团队项目(20110150)
关键词
二氯甲烷
生物降解
甲基杆菌
分离鉴定
降解性能
dichloromethane
biodegradation
methylobacterium
isolation and identification
degradation characteristics
