title: [Denature gradient gel electrophoresis of stratal bacteria activation in oilfield under different pressure conditions].
abstract: OBJECTIVE
  To study the structure change of dominant microbial population during activation of stratal microflora under atmospheric pressure (1 MPa) and higher pressure (10 MPa) conditions.
  
  
  METHODS
  The water sample was from Zhan 3 x 24 well produced water in Shengli Oilfield. We activated the bacteria in the water sample under atmospheric pressure and higher pressure, and collected samples at different time intervals. These samples were analyzed by denature gradient gel electrophoresis (DGGE).
  
  
  RESULTS
  Based on the analysis of the number and lightness of DGGE bands, we studied the change of the microbial community diversity activation of stratal bacteria. The species number and total quantity of dominant microbial population were not abundant under oil reservoir conditions. After injecting activation agent, some bacteria grew and reproduced quickly along with the enhancement of nutrition condition, and the structure of dominant microbial population changed.
  
  
  CONCLUSIONS
  Compared to atmospheric pressure condition, the number of DGGE bands was fewer under higher pressure condition, which indicated that only a few microbial species adapted high pressure conditions. The delayed increase of DGGE bands occurred apparently under higher pressure conditions. In late activation period, the change of DGGE bands was slight, which indicated that, the structure of dominant microbial population readjusted successfully and reached a new dynamic balance. This paper lays the foundation for explaining the relationship between laboratory study and field effect evaluation of microbial flooding.
authors.affiliation: Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China. mtbao@mail.ouc.edu.cn
authors.forename: Mutai
authors.initials: M
authors.lastname: Bao
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.forename: Qingguo
authors.initials: Q
authors.lastname: Chen
authors.forename: Guangjun
authors.initials: G
authors.lastname: Gao
authors.forename: Ximing
authors.initials: X
authors.lastname: Li
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D004275:DNA, Ribosomal / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D010578:Petroleum; D011312:Pressure
chemical_list: D004275:DNA, Ribosomal; D010578:Petroleum