title: Development of a novel integrated process for co-production of β-galactosidase and ethanol using lactose as substrate.
abstract: A novel integrated process was developed successfully for co-production of β-galactosidase and ethanol using lactose as substrate, containing fermentation (Kluyveromyces lactis), isolation, permeabilization (a new recycling process) and spray drying. Firstly, a new fed-batch strategy optimized co-produced β-galactosidase at 105.91U/mL and ethanol at 32.16mg/mL, 4.40-fold and 10.82-fold increase over the results from initial conditions, respectively. Then a new mathematic model for the recycling permeabilization was established successfully. As expected, the total cells sediment from isolation of the fed-batch culture was permeabilized completely by distilled ethanol from broth supernatant. More amazedly, the specific activity of β-galactosidase product by spray drying the permeabilized cells reached 2.61U/mg, meeting the demand of commercial products. Furthermore, the ethanol product at 33.8% (v/v) was obtained from the novel integrated process, which could be applied for various applications. To conclude, the novel integrated process might be a feasible strategy to scale up for industrialization.
authors.affiliation: Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China.
authors.forename: Shengping
authors.initials: S
authors.lastname: You
authors.affiliation: Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China.
authors.forename: Jianye
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China.
authors.forename: Qingdian
authors.initials: Q
authors.lastname: Yin
authors.affiliation: Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China; State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, PR China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, PR China; Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, PR China. Electronic address: qiwei@tju.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Qi
authors.affiliation: Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China; State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, PR China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, PR China; Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, PR China.
authors.forename: Rongxin
authors.initials: R
authors.lastname: Su
authors.affiliation: Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China; State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, PR China.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: He
mesh_terms: D061249:Batch Cell Culture Techniques; D019149:Bioreactors / Q000382:microbiology; D002244:Carbon / Q000494:pharmacology; D002463:Cell Membrane Permeability / Q000187:drug effects; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007716:Kluyveromyces / Q000187:drug effects / Q000378:metabolism; D007785:Lactose / Q000378:metabolism*; D009584:Nitrogen / Q000494:pharmacology; D010100:Oxygen / Q000494:pharmacology; D013379:Substrate Specificity / Q000187:drug effects; D013997:Time Factors; D001616:beta-Galactosidase / Q000096:biosynthesis*
chemical_list: D000431:Ethanol; D002244:Carbon; D001616:beta-Galactosidase; D007785:Lactose; D009584:Nitrogen; D010100:Oxygen
keywords: Ethanol; Integrated process; Kluyveromyces lactis; Lactose; β-Galactosidase