中文摘要：

从青海花土沟油田分离出两株高效原油降解混合菌bios2-1，bios2-2，经细菌的生理生化和16SrDNA基因序列鉴定，发现bios2-1与土壤短芽孢杆菌（Brevibacillus agri）的相似性为99％，bios2-2与短芽孢杆菌属中的Brevibacillus levickii的相似性为95％，认为是短芽孢杆菌属中的一个新种。当以花土沟原油为惟一碳源时，培养7d后，混合菌对原油的降解率可达70％左右。气相色谱和族组分分析表明，混合菌作用后，原油的轻质组分含量明显增加，重质组分含量明显降低，同时原油的粘度也降低了30．26％，凝固点降低了7．5℃。

英文摘要：

Two crude oil degradation bacillus of bios2-1 and bios2-2 were isolated and screened from Qinghai Huatugou Oilfield. The experimental results of the morphological structure, physiological characteristics and the comparison of its whole sequence of 16SrDNA with the type strains in Genebank show that 16SrDNA of the stain bios2-1 and that of Brevibacillus agri was more than 99 percent of homogenous. But the bios2-2 and that of Brevibacillus tevickii was only 95 percent of homogenous, which is regarded as a new strain of bacillus. Using Huatugou oil as the sole carbon source, the mixed strains have high degrading capacity for crude oil with degradation rate about 70% after culturing 7 d. The gas chromatography and the group composition analysis indicate that the light portions of the crude oil obviously increase, meanwhile, the weight portions obviously decrease after the mixed strains action. And the viscosity decreases 30.26% , the freezing point decreases 7.5 ℃.