title: Continuous ethanol production from sugarcane molasses using a newly designed combined bioreactor system by immobilized Saccharomyces cerevisiae.
abstract: Continuous ethanol fermentation using polyvinyl alcohol (PVA), immobilized yeast, and sugarcane molasses (22 and 35°Bx) with 8 g/L urea was run in a combined bioreactor system consisting of three-stage tubular bioreactors in series. The effect of the dilution rate (D) at 0.0037, 0.0075, 0.0117, 0.0145, 0.018, and 0.0282 H(-1) on continuous ethanol fermentation was investigated in this study. The results showed that D had a significant effect on fermentation efficiency, sugar-utilized rate, ethanol yield, and ethanol productivity in this designed continuous fermentation system. The D had a linear relationship with residual sugar and ethanol production under certain conditions. The highest fermentation efficiency of 83.26%, ethanol yield of 0.44 g/g, and the lowest residual sugar content of 6.50 g/L were achieved at 0.0037 H(-1) in the fermentation of 22°Bx molasses, indicating that the immobilization of cells using PVA, sugarcane pieces, and cotton towel is feasible and the established continuous system performs well.
authors.affiliation: School of Bioscience and Bioengineering, South China University of Technology, Panyu, Guangzhou, People's Republic of China.
authors.forename: Wanxia
authors.initials: W
authors.lastname: Xu
authors.forename: Lei
authors.initials: L
authors.lastname: Liang
authors.forename: Zhentao
authors.initials: Z
authors.lastname: Song
authors.forename: Mingjun
authors.initials: M
authors.lastname: Zhu
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D018914:Cells, Immobilized / Q000166:cytology / Q000378:metabolism; D000431:Ethanol / Q000737:chemistry / Q000378:metabolism*; D008965:Molasses; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism*; D031786:Saccharum / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000431:Ethanol
keywords: continuous fermentation; dilution rate; ethanol; immobilization; sugarcane molasses