title: Isolation, identification and utilization of thermophilic strains in aerobic digestion of sewage sludge.
abstract: Two representative thermophilic bacterial strains (T1 and T2) were isolated from a one-stage autothermal thermophilic aerobic digestion pilot-scale reactor. 16S rRNA gene analysis indicated that they were Hydrogenophilaceae and Xanthomonodaceae. These isolated strains were inoculated separately and/or jointly in sewage sludge, to investigate their effects on sludge stabilization under thermophilic aerobic digestion condition. Four digestion conditions were tested for 480 h. Digestion without inoculation and inoculation with strain T2, as well as joint- inoculation with strains T1 and T2, achieved 32.6%, 43.0%, and 38.2% volatile solids (VS) removal, respectively. Removal in a digester inoculated with stain T1 only reached 27.2%. For the first 144 h, the three inoculated digesters all experienced higher VS removal than the digester without inoculations. Both specific thermophilic strains and micro-environment significantly affected the VS removal. DGGE profiles revealed that the isolated strains T1 and T2 can successfully establish in the thermophilic digesters. Other viable bacteria (including anaerobic or facultative microbes) also appeared in the digestion system, enhancing the microbial activity.
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800, Dongchuan Rd., Shanghai 200240, China.
authors.forename: Shugen
authors.initials: S
authors.lastname: Liu
authors.forename: Nanwen
authors.initials: N
authors.lastname: Zhu
authors.forename: Loretta Y
authors.initials: LY
authors.lastname: Li
authors.forename: Haiping
authors.initials: H
authors.lastname: Yuan
mesh_terms: D000332:Aerobiosis; D001419:Bacteria / Q000235:genetics* / Q000302:isolation & purification*; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D058645:Denaturing Gradient Gel Electrophoresis; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000032:analysis; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology*; D013045:Species Specificity; D013696:Temperature; D013997:Time Factors; D014835:Volatilization
chemical_list: D012336:RNA, Ribosomal, 16S; D012722:Sewage; D009584:Nitrogen