煤矿污染土壤降解苯并（a）芘微生物多样性及降解能力研究

摘要

Soil microbes from coal mining areas of Lucaogou coal mine in Xinjiang was studied with medium supple-mented with benzo(a)pyrene (50 mg/L) as the sole carbon source training for three generations (60 days per genera-tion);PCR-DGGE approach was adopted to understand benzo( a) pyrene-degrading microbial taxa features and diver-sity from the different level of polluted soil samples collected from the mining areas;High performance liquid chroma-tography ( HPLC) was used to measure degradation ability of benzene( a) pyrene of every generation of stress training microbial group.The PCR-DGGE results showed that: there are differences in microbial aroma and thickness index ( H) , abundance ( S) , and evenness ( E) from different pollution levels of the original samples and the third genera-tion of stress culture samples with benzo( a) pyrene.Among them the culture of heavily polluted soil had the most a-bundant benzo( a) pyrene degradable microbial cluster.Clones of dominant bands mainly belong to Proteobacteria, Bacteroidetes, and Actinobacteria.It was found through HPLC determination that the degradation rate of benzo(a)py-rene by cluster microbe from heavily polluted sample obviously higher than those from lightly and/or moderate polluted samples, the gap was as high as 78.4%.The studies suggested that the polluted soil in coal extractive area in Lucao-gou coal mine in Xinjiang may store benzo( a) pyrene degradable microbial resources.%以苯并（a）芘（50 mg／L）为唯一碳源，对新疆芦草沟煤矿开采区土壤微生物进行3代胁迫培养（每代60 d）；采用PCR-DGGE方法了解不同污染程度土样中降解苯并（ a）芘的微生物类群和多样性特点；利用高效液相色谱（ HPLC）测定胁迫培养每代培养物混合菌群对苯并（ a）芘的降解能力。 PCR-DGGE结果显示：不同污染程度原始样品与苯并（a）芘胁迫培养第3代培养物的微生物香浓指数（H）、丰度（S）和均匀度（E）有所不同，其中重度污染培养物降解苯并（ a）芘的微生物类群最丰富。对优势条带进行克隆，其主要归属于变形菌门（ Proteobacteria）、拟杆菌门（ Bacteroidetes）和放线菌门（ Actinobacteria）。经HPLC检测发现重度污染样品中的群体微生物对苯并（a）芘的降解率明显高于轻度和中度污染样品，达到78．4％。研究表明新疆芦草沟煤矿开采区污染的土壤中可能蕴藏着降解苯并（ a）芘的微生物资源。