华北某油田石油降解菌的筛选及降解特性

以石油为唯一碳源，从华北某油田污染土壤中筛选出石油降解菌12株。其中5株菌有较强降解能力，分别编号为z-3、z-6、z-7、z-8和z-b，在30℃，160 r/min摇床培养10 d后，菌株对石油降解率分别为63.8%、34.2%、44.8%、50.5%和42.3%。通过生理生化和分子生物学鉴定，确定这5株菌分别属于假单胞菌属（Pseudomonas）、根瘤菌属（Rhizobium）、假黄单胞菌属（Pseudoxanthomonas）、假单胞菌属（Pseudomonas）、鞘氨醇单胞菌属（Sphingomonas）。通过对这5株菌生物量、脱氢酶及邻苯二酚 2，3-双加氧酶活性的监测，发现生物量及酶活性与石油降解能力具有直接关系。最后，对5株菌的生长条件进行优化，其中z-3、z-6、z-7和z-b菌株对石油降解率较优化前提高10%左右。

Isoloating of petroleum degrading strains and biodegrading characteristics in an oil field of northern China

Twelve petroleum degrading becterial strains were isoloated from oil-contaminated soil in northern China,which can use oil as the sole carbon nutrition for their growth.Five strains named as z-3,z-6,z-7,z-8 and z-b,had strong oil degradation activity,and their degradation rates were 63.8%,34.2%,44.8%,50.5% and 42.3%,respectively at 30℃,160 r/min for 10 days.Based on the results of physiological and biochemical characteristics as well as molecular biological analysis,the five strains were identified as Pseudomonas sp., Rhizobium sp.,Pseudoxanthomonas sp., Pseudomonas sp.,and Sphingomonas sp.The test for growth of five strains and activity of dehydrogenase and C230a showed that the petroleum biodegradation ability was relevant to oxidase activity and microbial biomass.After optimizing the growth conditions of five strains,the oil degradation rates of z-3,z-6,z-7 and z-b were 10% higher than before.