title: Organic loading rate shock impact on operation and microbial communities in different anaerobic fixed-bed reactors.
abstract: For the fixed-bed reactors in this experiment, during 40 days of stable operation and under different organic loading shocks, biogas production remained stable at 21 L, effluent pH remained between 6.8 and 7.5, and chemical oxygen demand (COD) removal efficiency and the biogas methane content were greater than 80% and 75%, respectively. The community was analyzed using denaturing gradient gel electrophoresis (DGGE), 16S rRNA gene clone library screening, and quantitative PCR. Findings revealed that bacteria and methanogenic archaea were typically dominant in the adhering sludge. Methanomicrobiales was identified in carbon fiber carriers, they were breeding slowly, and attached easily. The 16S rRNA gene concentration of methanogenic archaea was higher in the adhering sludge than in the deposited sludge. Our results indicated that the colonization of the microorganism played a very important role in the carbon fiber carriers, as well as in the improvement of sludge activity and the shock resistance of the reactor.
authors.affiliation: College of Agronomy and Biotechnology/Center of Biomass Engineering, China Agricultural University, Beijing 100193, China. zhy@ybu.edu.cn
authors.forename: Hongyan
authors.initials: H
authors.lastname: Zhao
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Jiajia
authors.initials: J
authors.lastname: Li
authors.forename: Xufeng
authors.initials: X
authors.lastname: Yuan
authors.forename: Renzhe
authors.initials: R
authors.lastname: Piao
authors.forename: Wanbin
authors.initials: W
authors.lastname: Zhu
authors.forename: Hulin
authors.initials: H
authors.lastname: Li
authors.forename: Xiaofen
authors.initials: X
authors.lastname: Wang
authors.forename: Zongjun
authors.initials: Z
authors.lastname: Cui
mesh_terms: D000693:Anaerobiosis / Q000187:drug effects; D001419:Bacteria / Q000187:drug effects* / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D058645:Denaturing Gradient Gel Electrophoresis; D005232:Fatty Acids, Volatile / Q000032:analysis; D008697:Methane / Q000378:metabolism; D009930:Organic Chemicals / Q000494:pharmacology*; D010100:Oxygen / Q000494:pharmacology; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013997:Time Factors; D014865:Waste Disposal, Fluid
chemical_list: D005232:Fatty Acids, Volatile; D009930:Organic Chemicals; D012336:RNA, Ribosomal, 16S; D008697:Methane; D010100:Oxygen