Bioenergy Group, Agharkar Research Institute, Pune, 411004, India.
National Centre for Cell Science, Ganeshkhind, Pune, 411007, India.
Environ Sci Pollut Res Int. 2021 Aug;28(30):40288-40307. doi: 10.1007/s11356-021-13666-3. Epub 2021 Apr 12.
Microbial activities within oil reservoirs have adversely impacted the world's majority of oil by lowering its quality, thereby increasing its recovery and refining cost. Moreover, conventional method of extraction leaves behind nearly two-thirds of the fossil fuels in the oil fields. This huge potential can be extracted if engineered methanogenic consortium is adapted to convert the hydrocarbons into natural gas. This process involves conversion of crude oil hydrocarbons into methanogenic substrates by syntrophic and fermentative bacteria, which are subsequently utilized by methanogens to produce methane. Microbial diversity of such environments supports the viability of this process. This review illuminates the potentials of abundant microbial groups such as Syntrophaceae, Anaerolineaceae, Clostridiales and Euryarchaeota in petroleum hydrocarbon-related environment, their genetic markers, biochemical process and omics-based bioengineering methods involved in methane generation. Increase in the copy numbers of catabolic genes during methanogenesis highlights the prospect of developing engineered biofuel recovery technology. Several lab-based methanogenic consortia from depleted petroleum reservoirs and microcosm studies so far would not be enough for field application without the advent of multi-omics-based technologies to trawl out the bottleneck parameters of the enhanced fuel recovery process. The adaptability of efficient consortium of versatile hydrocarbonoclastic and methanogenic microorganisms under environmental stress conditions is further needed to be investigated. The improved process might hold the potential of methane extraction from petroleum waste like oil tank and refinery sludge, oil field deposits, etc. What sounds as biodegradation could be a beginning of converting waste into wealth by recovery of stranded energy assets.
油藏中的微生物活动降低了世界上大多数石油的质量，从而增加了其回收和精炼成本，对其产生了负面影响。此外，常规的开采方法会使油田中近三分之二的化石燃料遗留下来。如果将工程化的产甲烷菌联合体适应将碳氢化合物转化为天然气，就可以提取出这些巨大的潜力。这个过程涉及到通过共生和发酵细菌将原油碳氢化合物转化为产甲烷底物，然后产甲烷菌利用这些底物产生甲烷。这些环境中的微生物多样性支持了这个过程的可行性。这篇综述阐述了丰富的微生物群体（如互营菌科、厌氧绳菌科、梭菌目和广古菌门）在石油碳氢化合物相关环境中的潜力，它们的遗传标记物、生化过程以及涉及甲烷生成的组学生物工程方法。在产甲烷过程中，代谢基因的拷贝数增加，这突显了开发工程生物燃料回收技术的前景。在多组学技术出现之前，从枯竭的石油储层和微宇宙研究中获得的几种基于实验室的产甲烷联合体还不足以应用于现场，因为这些技术可以挖掘出增强燃料回收过程的瓶颈参数。还需要进一步研究高效多功能烃类降解和产甲烷微生物联合体在环境胁迫条件下的适应性。改进后的工艺可能具有从石油废物（如油罐和炼油厂污泥、油田沉积物等）中提取甲烷的潜力。听起来像是生物降解的过程，可能是通过回收搁浅的能源资产将废物转化为财富的开始。
