Changes of bacterial and archaeal communities in glycerol-fed anaerobic digester on operation time
1Dept. of Microbiology, Pusan National University, 2EnvironSoft Co., Ltd. , 3Dept. of Environmental Engineering, Pusan National University
Glycerol can be produced as a byproduct on the process of biodiesel production, and the utilization of glycerol should be developed with industrialization of bioenergy production. The samples used in this study were harvested from a single stage anaerobic digester of 15.4 liter, which was operated to investigate the effect of mixing glycerol-containing wastewater into anaerobic digestion, on methane gas production rate. The wastewater contains 5% glycerol content (v/v) and the wastewater was fed as much as 15% of the total working volume (v/v). Biomass samples were harvested on 0, 1, 8, 17, 23, and 34-d after operation of the anaerobic digester, and the bacterial and archaeal communities in the samples were analyzed by using 454 pyrosequencing technique. On operation time, methane production rate increased from 0.49 L-CH3/removed g-COD to 0.55 L-CH3/removed g-COD compared with the case of which only food wastewater was supplied without glycerol-containing wastewater as the input-substrate for anaerobic digestion. “Chloroflexi” and “Firmicutes” were identified as the main bacterial phyla, but there was slight decrease of “Chloroflexi” group and slight increase of “Firmicutes” group on operation time. The result on archaeal community showed that the abundance of hydrogenotrophic methanogen such as “Methanospirillaceae” increased on operation time even thought there was acetoclastic methanogen such as “Methanosaetaceae” as the highest abundant group. According to the above results, glycerol-fed anaerobic digestion can recovery energy more from a waste of bioenergy production process by promoting methane production anaerobic digestion which can be desirable to accelerate the development of bioenergy production.
keywords:glycerol,anaerobic digestion,pyrosequencing,bacterial communigy,archaeal chomunity