红三叶草根际区石油降解菌的筛选及降解性能

从石油污染的土壤红三叶草（nifoliumrepensLinn）根际修复区中分离筛选得到4株以原油作为惟一碳源和能源进行生长繁殖的高效石油降解菌。通过菌落形态、显微镜个体形态观察、生理生化鉴定以及菌株16SrDNA序列分析，初步鉴定4株优势降解菌分别为动性杆菌、藤黄微球菌、蜡状芽孢杆菌和短小芽孢杆菌。采用气相色谱／质谱（GC／MS）法分析4株混合菌对石油烃的降解性能。结果表明：在摇床培养条件下，混合菌54d对总石油烃的生物降解率达到90．50％，较对照高67．72％。随着生物降解时间的延长，石油组分中的正构烷烃、异构烷烃及环烷烃相对总量均呈减小趋势，而芳香烃和其他醇类、醛和酸类的相对含量则有所增加。

Screening of oil degrading strains in Trifolium repens Linn rhizosphere and its biodegrading characteristics

Four high-efficient oil-degrading strains were isolated from the petroleum-contaminated soil which collected from Trifolium repens Linn rhizosphere for petroleum containment soil and with crude oil as sole carbon source. The strains were identified as Planomicrobium chinense (T), Micrococcus luteus, Bacillus cereus and Bacillus pumilus based on their morphology, physio-biochemical characteristics and sequence analysis by 16S rDNA. The oil degrading capacities of four strains were analyzed by GC/MS. The results indicated that the oil degradation rate could reach 90.50% after 54 d by mixed strain, which was 67.72% higher than the control. The relative contents of the normal alkanes, isomerization alkane and cycloparafin hydrocarbon decreased with the biodegradation time prolonged. The relative contents of aromatic hydrocarbons, alcohols, aldehydes and acids increased.