title: Effect of starch addition on the biological conversion and microbial community in a methanol-fed UASB reactor during long-term continuous operation.
abstract: The effect of starch addition on the microbial composition and the biological conversion was investigated using two upflow anaerobic sludge bracket (UASB) reactors treating methanolic wastewater: one reactor was operated with starch addition, and another reactor was operated without starch addition. Approximately 300 days of operation were performed at 30 kg COD/m(3)/d, and then, the organic load of the reactors was gradually increased to 120 kg COD/m(3)/d. Successful operation was achieved at 30 kg COD/m(3)/d in both reactors; however, the methanol-fed reactor did not perform well at 120 kg COD/m(3)/d while the methanol-starch-fed reactor did. The granule analysis revealed the granule developed further only in the methanol-starch-fed reactor. The results of the microbial community analysis revealed more Methanosaeta cells were present in the methanol-starch-fed reactor, suggesting the degradation of starch produced acetate as an intermediate, which stimulated the growth of Methanosaeta cells responsible for the extension of granules.
authors.affiliation: National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, Ibaraki 305-0053, Japan.
authors.forename: Takuro
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Feng
authors.initials: F
authors.lastname: Yan
authors.forename: Shintaro
authors.initials: S
authors.lastname: Takahashi
authors.forename: Yu-You
authors.initials: YY
authors.lastname: Li
mesh_terms: D001483:Base Sequence; D019149:Bioreactors; D015342:DNA Probes; D000432:Methanol / Q000008:administration & dosage*; D008855:Microscopy, Electron, Scanning; D010100:Oxygen / Q000737:chemistry; D013213:Starch / Q000008:administration & dosage*
chemical_list: D015342:DNA Probes; D013213:Starch; D010100:Oxygen; D000432:Methanol