Ali Shah Fayyaz, Mahmood Qaisar, Maroof Shah Mohammad, Pervez Arshid, Ahmad Asad Saeed
Department of Environmental Sciences, COMSATS Institute of Information Technology, Abbottabad 22060, Pakistan.
ScientificWorldJournal. 2014 Feb 19;2014:183752. doi: 10.1155/2014/183752. eCollection 2014.
Anaerobic digestion is the method of wastes treatment aimed at a reduction of their hazardous effects on the biosphere. The mutualistic behavior of various anaerobic microorganisms results in the decomposition of complex organic substances into simple, chemically stabilized compounds, mainly methane and CO2. The conversions of complex organic compounds to CH4 and CO2 are possible due to the cooperation of four different groups of microorganisms, that is, fermentative, syntrophic, acetogenic, and methanogenic bacteria. Microbes adopt various pathways to evade from the unfavorable conditions in the anaerobic digester like competition between sulfate reducing bacteria (SRB) and methane forming bacteria for the same substrate. Methanosarcina are able to use both acetoclastic and hydrogenotrophic pathways for methane production. This review highlights the cellulosic microorganisms, structure of cellulose, inoculum to substrate ratio, and source of inoculum and its effect on methanogenesis. The molecular techniques such as DGGE (denaturing gradient gel electrophoresis) utilized for dynamic changes in microbial communities and FISH (fluorescent in situ hybridization) that deal with taxonomy and interaction and distribution of tropic groups used are also discussed.
厌氧消化是一种废物处理方法，旨在减少其对生物圈的有害影响。各种厌氧微生物的共生行为导致复杂有机物质分解为简单的、化学稳定的化合物，主要是甲烷和二氧化碳。由于四类不同微生物（即发酵细菌、互营细菌、产乙酸细菌和产甲烷细菌）的协同作用，复杂有机化合物才能转化为CH4和CO2。微生物采用各种途径来规避厌氧消化器中的不利条件，例如硫酸盐还原菌（SRB）和产甲烷菌对同一底物的竞争。甲烷八叠球菌能够利用乙酸裂解途径和氢营养途径产生甲烷。本综述重点介绍了纤维素微生物、纤维素结构、接种物与底物比例、接种物来源及其对甲烷生成的影响。还讨论了用于微生物群落动态变化的分子技术，如变性梯度凝胶电泳（DGGE），以及用于处理分类学、营养群体的相互作用和分布的荧光原位杂交（FISH）技术。
