Study On The Type And Properties Of Surfactants Produced By Microbial Strain

Microbial Enhanced Oil Recovery (MEOR) was the way of oil exploitation technology which was designed to drive residual oil by microbe and their metabolic production. Among the total, utilization of surfactants which enhanced oil recovery is focal point.Bacterium which would produce biosurfactant were isolated and purified from aquifer stratum and pedotheque in DaQing oil field. The 3 high biosurfactant strains (HD-322-2,T10-3, S6-1) were initially screened by blood plate and excluding oil cycle. The results of thin-laver chromatography showed that biosurfactants were lipopeptid. The types of biosurfactants which were further analyzed by infrared spectrum were lipopeptid. Among the total, the strain which output of biosurfactant was highest was HD-322-2 and the output was 312mg/L. The results showed that biosurfactant had good thermal stability,well range of pH and find tolerance of concentration of NaCI through the study of physico-chemicial property on biosurfactant generated from strain HD-322-2.The strain was confirmed Bacillus subilis strain by appearance observation, the nature determination of physiology and biochemistry and analysis of 16S rDNA. Moreover, the analysis of 16S rDNA showed that strain HD-322-2 was conformed to Bacillus subilis strain CD-25 and the rate was 99%.