Department of Food, Agricultural and Biological Engineering, The Ohio State University, Ohio Agricultural Research and Development Center, 1680 Madison Ave., Wooster, OH 44691, USA.
Bioresour Technol. 2013 May;136:574-81. doi: 10.1016/j.biortech.2013.02.073. Epub 2013 Mar 5.
Reactor performance and microbial community dynamics were investigated during solid state anaerobic digestion (SS-AD) of corn stover at mesophilic and thermophilic conditions. Thermophilic SS-AD led to faster and greater reductions of cellulose and hemicelluloses during the first 12 days compared to mesophilic SS-AD. However, accumulation of volatile fatty acids (VFAs) was 5-fold higher at thermophilic than mesophilic temperatures, resulting in a large pH drop during days 6-12 in the thermophilic reactors. Culture-based enumeration revealed 10-50 times greater populations of cellulolytic and xylanolytic microbes during thermophilic SS-AD than mesophilic SS-AD. DGGE analysis of PCR amplified 16S rRNA genes showed dynamic shifts, especially during the thermophilic SS-AD, of bacterial and archaeal communities over the 38 days of SS-AD as a result of acclimation of the initial seed microbial consortia to the lignocellulosic feedstock. The findings of this study can guide future studies to improve efficiency and stability of SS-AD.
在中温和高温条件下进行玉米秸秆固态厌氧消化（SS-AD）时，研究了反应器性能和微生物群落动态。与中温 SS-AD 相比，高温 SS-AD 在前 12 天内导致纤维素和半纤维素更快、更大幅度的减少。然而，高温时挥发性脂肪酸（VFAs）的积累比中温时高 5 倍，导致高温反应器中在第 6-12 天 pH 值大幅下降。基于培养的计数显示，高温 SS-AD 中纤维素分解菌和木聚糖分解菌的数量比中温 SS-AD 高 10-50 倍。PCR 扩增 16S rRNA 基因的 DGGE 分析显示，由于初始种子微生物群落对木质纤维素原料的适应，在 38 天的 SS-AD 过程中，细菌和古菌群落发生了动态变化，尤其是在高温 SS-AD 期间。本研究的结果可以指导未来的研究，以提高 SS-AD 的效率和稳定性。
