延长油田增油细菌的筛选及其降解特性研究

【目的】分离筛选可提高原油采收率的增油细菌。【方法】以原油为唯一碳源，利用富集培养和稀释平板法从延长油田油污土壤中分离增油菌株；通过排油能力测定、原油附着与乳化性能观察、代谢产物表面活性物质分析及原油降解试验，从分离的菌株中筛选增油性能较好的细菌菌株，并通过菌落形态观察、生理生化特性测定及16S rDNA全序列分析，对筛选的排油及乳化性能较好的细菌进行鉴定。【结果】①从原油及油污土壤中筛选出25株细菌，从中选择10株代谢产物中含有表面活性成分脂肽或糖脂的优势细菌用于后续试验，该10株菌均可导致原油物理化学性质发生变化，提高原油在油水发酵液中的乳化度，同时降低原油对瓶壁的附着度。②4株乳化及排油效果较好的菌株6-1、P₁H₁₃₂、AP₁H₁₁和6-3Y对原油的降解效果较好，与原油作用后，原油组分中有34.0%～55.3%的组分被细菌完全降解而消失。③4株细菌的鉴定结果为：6-1为Rhizobium pusense，P₁H₁₃₂为Zhihengliuella aestuarii，AP₁H₁₁为Bacillus licheniformis，6-3Y为B.aryabhattai。【结论】获得的10株增油细菌具有良好的增油潜力，其中已鉴定的4株细菌可用于进一步的增油试验，在微生物采油和原油污染处理方面具有应用潜力。

Isolation of bacteria for MEOR in the Yanchang oilfield and their biodegradation characteristics

【Objective】 The study was to separate and screen bacteria strains for MEOR.【Method】 Crude oil degrading strains isotaled by enrichment culture and direct plate-separation method using crude oil was used as the sole carbon source;Isolate bacteria strains were tested to see if they could make a big difference to improve oil production by determining ejecting capability,observing emulsion and adhesion of crude oil,and analysing surface-active components the culture broth and the changes of crude oil components.Four bacteria with good capability of ejecting oil and emulsion were identified by morphological and physiological-biochemical tests and 16S rDNA sequence analysis.【Result】 ①Ten bacteria strains which could produce surfactant contain glycolipid and lipopeptide were selected from 25 isolated bacteria strains;All ten of them could lead to the transformation of physical and chemical properties of petroleum and improve emulsion and adhesion of petroleum.②Four strains named 6-1,P1H132,AP1H11 and 6-3Y could effectively degrade the crude oil,34.0%-55.3% of components completely degraded by tested bacteria.③Four bacteria were identified as Rhizobium pusense(6-1),Zhihengliuella aestuarii(P1H132),Bacillus licheniformis(AP1H11),Bacillus aryabhattai(6-3Y).【Conclusion】 All ten isolated bacteria have potential to enhance the crude oil recovery,four of whom can be further applied to microbe flooding test and show a good potential for MEOR and bioremediation for oil-contaminated soil.