title: Nanofiltration concentration of extracellular glutathione produced by engineered Saccharomyces cerevisiae.
abstract: This study aimed to optimize extracellular glutathione production by a Saccharomyces cerevisiae engineered strain and to concentrate the extracellular glutathione by membrane separation processes, including ultrafiltration (UF) and nanofiltration (NF). Synthetic defined (SD) medium containing 20 g L(-1) glucose was fermented for 48 h; the fermentation liquid was passed through an UF membrane to remove macromolecules. Glutathione in this permeate was concentrated for 48 h to 545.1 ± 33.6 mg L(-1) using the NF membrane; this was a significantly higher concentration than that obtained with yeast extract peptone dextrose (YPD) medium following 96 h NF concentration (217.9 ± 57.4 mg L(-1)). This higher glutathione concentration results from lower cellular growth in SD medium (final OD600 = 6.9 ± 0.1) than in YPD medium (final OD600 = 11.0 ± 0.6) and thus higher production of extracellular glutathione (16.0 ± 1.3 compared to 9.2 ± 2.1 mg L(-1) in YPD medium, respectively). Similar fermentation and membrane processing of sweet sorghum juice containing 20 g L(-1) total sugars provided 240.3 ± 60.6 mg L(-1) glutathione. Increased extracellular production of glutathione by this engineered strain in SD medium and subsequent UF permeation and NF concentration in shortend time may help realize industrial recovery of extracellular glutathione.
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: Kiyotaka Y
authors.initials: KY
authors.lastname: Hara
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: D019149:Bioreactors; D003470:Culture Media / Q000737:chemistry; D005110:Extracellular Space / Q000378:metabolism*; D005285:Fermentation; D005374:Filtration / Q000379:methods*; D005818:Genetic Engineering; D005947:Glucose / Q000378:metabolism; D005978:Glutathione / Q000096:biosynthesis / Q000302:isolation & purification*; D036103:Nanotechnology / Q000379:methods*; D010461:Peptones / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics* / Q000378:metabolism*; D045868:Sorghum / Q000737:chemistry; D014462:Ultrafiltration / Q000379:methods
chemical_list: D003470:Culture Media; D010461:Peptones; D005978:Glutathione; D005947:Glucose
keywords: Extracellular glutathione; Nanofiltration; Saccharomyces cerevisiae; Synthetic defined medium; Yeast extract peptone dextrose medium