title: Real-time viable-cell mass monitoring in high-cell-density fed-batch glutathione fermentation by Saccharomyces cerevisiae T65 in industrial complex medium.
abstract: An on-line monitoring of viable-cell mass in high-cell-density fed-batch cultivations of Saccharomyces cerevisiae grown on an industrial complex medium was performed with an in situ capacitance probe fitted to a 50-l fermentor. Conventional off-line biomass determinations of several parameters, including dry cell weight (DCW), optical density at 600 nm wavelength (OD(600)), packed mycelial volume (PMV) and number of colony forming units (CFU), were performed throughout the bioprocess and then compared with on-line viable-cell concentrations measured using a capacitance probe. Capacitance versus viable biomass and all off-line biomass assay values were compared during glutathione fermentation in industrial complex culture media. As a result, the relationship between the number of colony forming units and capacitance with a correlation coefficient (R) of 0.995 was achieved. Simultaneously, compared with those determined by at-line indirect estimation methods including oxygen uptake rate (OUR) and carbon dioxide evolution rate (CER), the specific growth rates estimated by on-line capacitance measurement could be more reliable during glutathione fermentation. Therefore, it is concluded that a capacitance probe is a practical tool for real-time viable biomass monitoring in high-cell-density fed-batch cultivation in a complex medium.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237 Shanghai, P.R. China.
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Xiong
authors.forename: Mei-Jin
authors.initials: MJ
authors.lastname: Guo
authors.forename: Yuan-Xin
authors.initials: YX
authors.lastname: Guo
authors.forename: Ju
authors.initials: J
authors.lastname: Chu
authors.forename: Ying-Ping
authors.initials: YP
authors.lastname: Zhuang
authors.forename: Si-Liang
authors.initials: SL
authors.lastname: Zhang
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D003470:Culture Media / Q000737:chemistry*; D005285:Fermentation; D005978:Glutathione / Q000737:chemistry*; D007218:Industrial Microbiology / Q000295:instrumentation / Q000379:methods; D012441:Saccharomyces cerevisiae / Q000254:growth & development*
chemical_list: D003470:Culture Media; D005978:Glutathione