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

Benzo( a) pyrene-Degrading Microbial Diversity & Degradation Ability in Coal Mine Polluted Soil

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。

Soil microbes from coal mining areas of Lucaogou coal mine in Xinjiang was studied with medium supplemented with benzo（ a） pyrene（ 50 mg / L） as the sole carbon source training for three generations（ 60 days per generation）; PCR-DGGE approach was adopted to understand benzo（ a） pyrene-degrading microbial taxa features and diversity from the different level of polluted soil samples collected from the mining areas; High performance liquid chromatography（ 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 generation of stress culture samples with benzo（ a） pyrene. Among them the culture of heavily polluted soil had the most abundant 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） pyrene 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 Lucaogou coal mine in Xinjiang may store benzo（ a） pyrene degradable microbial resources.