一株采油用地衣芽孢杆菌厌氧生长代谢

Study on anaerobic growth metabolism of a Bacillus licheniformis strain

关键词:  芽孢杆菌  微生物采油  厌氧生长代谢  电子受体

Key words:  Bacillus  MEOR  anaerobic growth metabolism  electron acceptor

摘要:

为提高采油用外源菌油藏适应性和采油能力,以一株采油用地衣芽孢杆菌(Bacillus licheniformis)为对象,对其厌氧生长代谢和采油功能进行研究。结果表明:该菌株为兼性微生物,分别可以在好氧和厌氧条件下生长代谢,在好氧条件下生长较快,10 h到达峰值期,而厌氧条件下需要95 h,通过厌氧连续传代驯化后菌株厌氧生长代谢速率提高2.5倍;厌氧条件下提供电子受体可以提高菌株的乳化和产气能力,该菌株厌氧乳化指数达到100％,乳化剂产率为0.25 g/g底物,所产乳化剂为相对分子质量26 000的蛋白多糖类大分子复合物;该菌株厌氧代谢过程中同时产生二氧化碳气体和挥发性脂肪酸,随营养体系中电子受体含量增加产气量增加,而脂肪酸产物质量浓度降低;该菌株物模评价水驱基础上提高采收率达到16.0％。

Abstract:

In order to improve the adaptability and ability of oil recovery for exogenous microorganism, the anaerobic growth metabolism and recovery ability of one strain of the rmophilic Bacillus licheniformis was studied. It is found that this strain belongs to facultative bacteria, which could grow and metabolize under both aerobic and anaerobic conditions. Under aerobic conditions it grows rapider, which reaches the peak at 10 hours. Meanwhile, under anaerobic conditions it needs 95 hours to reach the peak. Its growth rate is 2.5 times higher than before after subcultivation and acclimationin anaerobic condition. Lectron acceptor could improvethe emulsification and gas production capacityofstrainsunder anaerobicconditions.The strain of anaerobic emulsification index reaches 100％, in which the emulsifier yield is 0.25 g/g of substrate. And the emulsifier production is about 26 000 large molecules produced by emulsifier glycoprotein compound; This strain of anaerobic metabolic process also produces carbon dioxide and volatile fatty acids, in which the gas production increases with the increase of electron acceptors, while the concentration of fat acid reduces. On the basis of water flooding, oil recovery of this strain can reach 16.0％.