原油降解菌的筛选及降油率比较

Screening of Crude Oil Degrading Bacteria and Comparison of Oil Degrading Rate

经牛肉膏蛋白胨液体培养基驯化、固体培养基分离纯化,从长庆油田措施废液集中处理后残渣中筛选出了5株具有较强降解石油能力的微生物菌株,将其分别编号为D1、D2、D3、D4、D5。通过形态学和生理生化实验对分离得到的纯种菌株进行鉴定,结果表明D1属于芽孢杆菌属(Bacillus sp.),D2属于链球菌属(Streptococcus sp.),D3属于黄杆菌属(Flavobacterium Bergey sp.),D4属于微球菌属(Micrococcus Cohn sp.),D5属于产碱菌属(Alcaligenes sp.)。将得到的5株纯菌株在牛肉膏蛋白胨液体培养基中培养3 d,分别按单株菌株5 mL、2种菌株以1:1的比例各5 mL、3种菌株以1:1:1的比例各5 mL的接种量,分别接种到原油液体培养基中培养,7 d后,按照《CJ/T 57-1999》标准测定原油降解率。比较原油降油率,得到2种菌株组合接种的降油率高于3种菌株组合高于单菌菌株。其中D1、D4按照1:1比例,各5 mL的接种量接种到原油液体培养基中得到的降油率最高,为89.39%。

Through cultivation and acclimation in the beef paste peptone liquid culture medium, separation and purification, 5 strains of microorganisms with strong petroleum degradation capacity were selected from the residue after concentrated treatment of Changqing oilfield wastewater, and they were numbered as D1, D2,, D3, D4, D5. The isolated strains were identified by morphology and physiological and biochemical tests. The results showed that D1 belonged to Bacillus sp., D2 belonged to Streptococcus sp., and D3 belonged to Flavobacterium sp., D4 belongs to Micrococcus Cohn sp. and D5 belongs to Alcaligenes sp. The obtained 5 strains of pure strain were cultured for 3 days in the beef paste peptone liquid culture medium. 5 m L of each strain, two strains of each strain at 1:1 ratio of 5 m L, and three strains at 1:1:1 ratio of 5 m L were inoculated in crude oil liquid medium. After 7 days, the degradation rate of crude oil was measured according to 'CJ/T 57-1999' standard. Comparing the crude oil degrading rate, the oil degradation rate of the 2 strains inoculated was higher than that of the 3 strains, and was also higher than that of the single strain. Among them, the oil degradation rate of D1 and D4 inoculated into crude oil liquid medium in the ratio of1:1 and the inoculation amount of each 5 m L was the highest, 89.39%.