title: Increased ethanol production from sweet sorghum juice concentrated by a membrane separation process.
abstract: The aim of this investigation was to attain high ethanol concentration by concentrating sweet sorghum juice using a two-step membrane separation process. Ultrafiltration permeation of the juice was used to remove residues, followed by nanofiltration concentration to increase the sugar concentration. The concentrated juice containing 180.0 g L(-1) sucrose, 59.3 g L(-1) glucose and 49.3 g L(-1) fructose supplemented with nitrogen sources (10 and 20 g L(-1) of yeast extract and polypeptone, respectively) was fermented by Saccharomyces cerevisiae BY4741 to produce 133.5 g L(-1) of ethanol (87.6% of theoretical yield) after 48 h fermentation. Importantly, the addition of lower concentrations of exogenous nitrogen sources (3 and 6 g L(-1) of yeast extract and polypeptone, respectively) or no exogenous nitrogen sources resulted in the production of 131.4 and 132.8 g L(-1) of ethanol (84.8% and 86.0% of theoretical yield), respectively, after 48 h fermentation.
authors.affiliation: Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 675-8501, Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Sasaki
authors.affiliation: Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 675-8501, Japan.
authors.forename: Yota
authors.initials: Y
authors.lastname: Tsuge
authors.affiliation: Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 675-8501, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Sasaki
authors.affiliation: Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Teramura
authors.affiliation: Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 675-8501, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Wakai
authors.affiliation: Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Kawaguchi
authors.affiliation: Bioscience and Biotechnology Center, Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Sazuka
authors.affiliation: Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Ogino
authors.affiliation: Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan; Biomass Engineering Program, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan. Electronic address: akondo@kobe-u.ac.jp.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kondo
mesh_terms: D001628:Beverages; D001709:Biotechnology / Q000379:methods*; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation / Q000187:drug effects; D007700:Kinetics; D008567:Membranes, Artificial; D036103:Nanotechnology; D009584:Nitrogen / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism; D045868:Sorghum / Q000737:chemistry*; D014462:Ultrafiltration
chemical_list: D008567:Membranes, Artificial; D000431:Ethanol; D009584:Nitrogen
keywords: Bioethanol; Nanofiltration; Saccharomyces cerevisiae; Sweet sorghum juice; Ultrafiltration