title: Continuous butanol fermentation from xylose with high cell density by cell recycling system.
abstract: A continuous butanol production system with high-density Clostridium saccharoperbutylacetonicum N1-4 generated by cell recycling was established to examine the characteristics of butanol fermentation from xylose. In continuous culture without cell recycling, cell washout was avoided by maintaining pH>5.6 at a dilution rate of 0.26 h(-1), indicating pH control was critical to this experiment. Subsequently, continuous culture with cell recycling increased cell concentration to 17.4 g L(-1), which increased butanol productivity to 1.20 g L(-1) h(-1) at a dilution rate of 0.26 h(-1) from 0.529 g L(-1) h(-1) without cell recycling. The effect of dilution rates on butanol production was also investigated in continuous culture with cell recycling. Maximum butanol productivity (3.32 g L(-1) h(-1)) was observed at a dilution rate of 0.78 h(-1), approximately 6-fold higher than observed in continuous culture without cell recycling (0.529 g L(-1) h(-1)).
authors.affiliation: Laboratory of Microbial Technology, Division of Applied Molecular Microbiology and Biomass Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan. zhengjin2811@gmail.com
authors.forename: Jin
authors.initials: J
authors.lastname: Zheng
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Tashiro
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yoshida
authors.forename: Ming
authors.initials: M
authors.lastname: Gao
authors.forename: Qunhui
authors.initials: Q
authors.lastname: Wang
authors.forename: Kenji
authors.initials: K
authors.lastname: Sonomoto
mesh_terms: D061249:Batch Cell Culture Techniques / Q000295:instrumentation*; D019149:Bioreactors / Q000382:microbiology*; D000440:Butanols / Q000191:economics / Q000378:metabolism*; D002452:Cell Count; D003013:Clostridium / Q000378:metabolism*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005285:Fermentation; D059027:Recycling / Q000379:methods*; D012212:Rheology / Q000295:instrumentation*; D014994:Xylose / Q000191:economics / Q000378:metabolism*
chemical_list: D000440:Butanols; D014994:Xylose