Impact of organic load shock on the dynamic transition of microbial communities during the anaerobic start-up process

This study investigated the shifts of bacterial and archaea diversity suffering the organic load shocks during the start-up. To demonstrate the effects of organic load shock, six reactors was operated in different OLR for 31 days. The community was analyzed using denaturing gradient gel electrophoresis (DGGE) and quantitative PCR. Findings revealed that bacteria diversity was the poorest and archaea quantity was the fewest when suffering OLR shock. MST and MSC were found to the more vulnerable methanogenic arch aea groups during organic overloading. Our results explained why gradually increasing OLR is good for favoring the growth of an active biofilm and reactor successful startup quickly during the start-up from the perspective of microbial. (C) 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).