Summary
In large-scale bioreactors inadequate mixing may impose a continually changing environment to a microbial culture. How the culture will response to such conditions can be studied by means of well designed laboratory-scale experiments. In a two-fermentor-system the influence of continually changing glucose concentrations on the fed-batch baker's yeast production was investigated. Experiments were carried out at different circulation rates and different ratios of the fermentor volumes. The imperfect mixing of the system caused a reduction of the biomass yield and an increase in the ethanol formation. Acetic acid and glyerol were produced as well, but no clear relationship between the circulation rate and the amount of metabolites formed could be observed. The difference in performance of the culture in both fermentors was exposed clearly by the respiration quotient and the (maximum) specific oxygen consumption rate.
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Abbreviations
- C i :
-
concentration (kg/m3)
- DOT:
-
dissolved-oxygen tension (% air saturation)
- F cir :
-
circulation flow (m3/s)
- F s :
-
substrate flow to the fermentor (m3/s)
- K i :
-
saturation constant (kg/m3)
- m s :
-
maintenance coefficient (kg/(kg DW·h))
- Q max :
-
(maximum) specific consumption (kg/(kg DW·h)) or production rate
- RQ :
-
respiration quotient (mol CO2/mol O2)
- TFS:
-
two-fermentor-system
- t :
-
time (s)
- t cir :
-
circulation time (s)
- V :
-
volume (m3)
- Y ij :
-
yield of componentj oni (kg/kg)
- μ:
-
specific growth rate (h-1)
- τ:
-
residence time
- τ:
-
gas flow rate (m3/h)
- 0:
-
value att=0
- 1:
-
smallest, uppermost fermentor
- 2:
-
biggest, lowest fermentor
- e :
-
ethanol
- f :
-
feed concentration
- i :
-
componenti
- j :
-
componentj
- lim:
-
oxidation capacity
- O:
-
O2, oxygen
- s :
-
substrate, glucose
- x :
-
biomass
- ox:
-
oxidation
References
Käppeli O, Gschwend-Petrik M, Fiechter A (1985) Transient responses ofSaccharomyces uvarum to a change of the growth-limiting nutrient in coninuous culture. J Gen Microbiol 131:47–52
Moser A (1985) Special cultivation techniques. In: Rehm H-J, Reed G (eds) Biotechnology Vol 2. VCH Verlagsgesellschaft, Weinheim, pp 311–347
Oosterhuis NMG (1984) Scale-up of bioreactors: a scale-down approach, PhD. Thesis, Delft University of Technology
Rieger M, Käppeli O, Fiechter A (1983) The role of limited respiration in the incomplete oxidation of glucose bySaccharomyces cerevisiae. J Gen Microbiol 129:653–661
Sokolov DP, Lirova SA, Sokolova EA (1983) Effect of cyclical changes in culturing conditions on the growth kinetics and physiological characteristics of yeasts. Microbiologiya 52:909–916
Sonnleitner B, Käppeli O (1986) Growth ofSaccharomyces cerevisiae is controlled by its limited respiration capacity: formulation and verification of a hypothesis. Biotechnol Bioeng. 28:927–937
Sweere APJ, Luyben KChAM, Kossen NWF (1987) Regime analysis and scale-down: tools to investigate the performance of bioreactors. Enz Microb Technol 9:386–398
Sweere APJ, Mesters JR, Kossen NWF, Luyben KChAM (1986) Regime analysis of the baker's yeast production. Proc Int Conf Bioreactor Fluid Dynamics, BHRA, Cambridge 15–17 April, pp 217–230
Sweere APJ, Janse L, Kossen NWF, Luyben KChAM (1987b) Experimental simulation of oxygen profiles and their influence on the baker's yeast production; Part II: Two-fermentor-system. Biotechnol Bioeng (in press)
Sweere APJ, Mesters JR, Janse L, Luyben KChAM, Kossen NWF (1987c) Experimental simulation of oxygen profiles and their influence on the baker's yeast production; Part I: One-fermentor-system. Biotechnol Bioeng (in press)
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Sweere, A.P.J., Matla, Y.A., Zandvliet, J. et al. Experimental simulation of glucose fluctuations. Appl Microbiol Biotechnol 28, 109–115 (1988). https://doi.org/10.1007/BF00694297
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DOI: https://doi.org/10.1007/BF00694297