一株苯并[a]芘高效降解真菌的筛选与降解特性  

Isolation of a fungal strain capable of degrading benzo [a] pyrene and its degradation characteristics

作　　者：顾平[1,2] 张倩茹[2] 周启星[2] 张颖[1] 杨肖娥[3] 

机构地区：[1]东北农业大学资源与环境学院,哈尔滨150030 [2]中国科学院沈阳应用生态研究所,中国科学院陆地生态过程重点实验室,沈阳110016 [3]浙江大学环境与资源学院,污染环境修复与生态健康教育部重点实验室,杭州310029

出　　处：《环境科学学报》2010年第2期354-360,共7页Acta Scientiae Circumstantiae

基　　金：国家高技术研究发展计划(863)项目(No.2006AA06Z386);污染环境修复与生态健康教育部重点实验室开放基金(No.EREH0710);教育部科技创新工程重大项目培育资金项目(No.707011)~~

摘　　要：从长期受多环芳烃(PAHs)污染的土壤中分离出一株能够降解苯并[a]芘(B[a]P)的真菌,经鉴定为绿色木霉(Trichoderma viride)(命名为BF-1),并对其以B[a]P为唯一碳源进行反复驯化,考察了B[a]P浓度、不同重金属和培养基对其降解能力的影响.结果表明,菌株BF-1在B[a]P浓度为5mg.L-1,32℃振荡培养约6d的条件下,降解速度最快,B[a]P的降解率达68.28%.BF-1在B[a]P浓度分别为10与25mg.L-1,32℃振荡培养6d的条件下,B[a]P的降解率分别为73.29%与87.36%.Cu2+(50mg.L-1)基本不影响BF-1对B[a]P的降解率;Cd2+(100mg.L-1)、Pb2+(300mg.L-1)对BF-1降解B[a]P有一定影响,但仍表现出较高的耐受能力;而Zn2+(200mg.L-1)对BF-1有明显的抑制作用.选用含5mg.L-1B[a]P的土豆葡萄糖液体培养基,6d后B[a]P的降解率为71.31%.对比前述实验结果表明,培养基对B[a]P降解率的影响并不明显.因此,BF-1的应用价值较高.A fungal strain,BF-1,with optimal degradation ability for the polycyclic aromatic hydrocarbon （PAH） benzo[a]pyrene （B[a]P） was isolated from long-term PAH-contaminated soil.The strain was identified as Trichoderma viride.The effects of B[a]P concentration,various heavy metals and culture media on the degradation ability of the fungal strain were further studied using repeated subcultures in liquid medium with B[a]P as the only carbon source.The highest degradation rate of 5 mg·L^-1 B[a]P by BF-1 was 68.28% after a 6-day culture at 32 ℃.After a 6-day oscillating culture at 32 ℃,the degradation rates of 10 and 25 mg·L^-1 B[a]P in the culture medium were 73.29% and 87.36%,respectively.Addition of Cu^2＋（50 mg·L^-1） could appreciably inhibit the biodegradation of B[a]P by BF-1,and Pb^2＋ （300 mg·L^-1） and Cd^2＋ （100 mg·L^-1） also affected the rate of degradation,but the strain had strong tolerance to Pb2＋ （300 mg·L^-1） or Cd^2＋ （100 mg·L^-1 ）.In particular,there was an obvious inhibitory effect of Zn2＋ （200 mg·L^-1） on the rate of degradation.After inoculation in potato dextrose broth culture media,BF-1 could degrade 5 mg·L^-1 B[a]P at a rate of 71.31% in 6 days,and compared with the results above,it was concluded that the culture media had minimal effect on the degradation of B[a]P.Therefore,fungal strain BF-1 should be valuable in degrading B[a]P because it can tolerate a wide range of culture conditions.

关 键 词：污染土壤 苯并[a]芘(B[a]P) 绿色木霉 生物修复 降解作用 

分 类 号：X172[环境科学与工程—环境科学]