一株分离自大庆油田原油样品中的产生物表面活性剂菌株的筛选与鉴定

Isolation and Identification of a Biosurfactant-producing Strain from Daqing Crude Oil

从大庆油田原油样品中,经富集培养和梯度稀释平板法初步筛选得到3株具有乳化活性的菌株.采用血平板法和排油圈法对这3株菌进行表面活性测定,其中一株菌株的表面活性最强,命名为DQ-1.对菌株的性质进行分析,发现该菌株具有耐高温、耐碱的特性;经过16S rRNA序列分析和进化树构建等将DQ-1鉴定为铜绿假单胞菌(Pseudomonas aeruginosa).通过TLC和HPLC等技术方法分离纯化DQ-1所产生的生物表面活性剂.通过HPLC-MS技术,得到纯化获得的生物表面活性剂的荷质比(M/Z)分别为:333.09,503.18,504.18,531.20,649.20,据文献报道,可以初步确定DQ-1所产生的生物表面活性剂为鼠李糖脂.

Three strains with the ability of emulsification were initially isolated from crude oil of Daqing oil field via enrichment method and series dilution operations.Blood plate and oil displacement protocol were performed to further assay surface activity of these strains and the strain which of most emulsification was obtained and named DQ-1.16S rRNA alignment result revealed that DQ-1 was Pseudomonas aeruginosa.Characteristic assay showed that DQ-1 was heat-tolerant and alkaline-resistant.Biosurfactant which produced by DQ-1 was collected via centrifugation and acidification.Then biosurfacntant was separated and purified through TLC and HPLC methods.Furthermore,through HPLC-MS assay,M/Z value of this purified surfactant were 333.09,503.18,504.18,531.20 and 649.20.According to literatures,we concluded that the surfactant produced by DQ-1was rhamnolipid.