Heterogeneous bioprocesses

Substituting these equations into the full equation for the effective rate in the S phase for a three-phase heterogeneous bioprocess at steady state... 

Figure 5.70. Kinetics of heterogeneous bioprocess Diagram of the specific rate of substrate use, as a function of the substrate concentration, s, varying the thickness of the biocatalytically active mass, d, for floe and film geometries. Monod kinetics appear as the boundary case at low d. Unrealistic cases are indicated with dashed lines. (Adapted from Atkinson, 1974 with permission of Pion, London.)...

Brognaux, A., Francis, F., Twizere, J.C., Thonart, P., and Delvigne, F. (2014) Scaie-down effect on the extracellular proteome of Escherichia coli correlation with membrane permeability and modulation according to substrate heterogeneities. Bioprocess Biosyst. Eng, 37 (8), 1469-1485. 

Al-Rubeai M Spier R (1989) Use of the MTT assay for the study of hybridoma cells in homogeneous and heterogeneous cultures. In Spier RE, Griffiths J, Stephenne J and Crooy P (eds) Advances in Animal Cell Biology and Technology for Bioprocesses, pp. 143-155. Butterworth, London. 

The process-engineering comparison between simple fermentation and a complex bioprocess such as that used for waste water treatment, shown in detail in Table 1.2, brings out the problems involved in quantifying practices used in complex cases multiple substrate kinetics operating in either sequential or parallel form mixed populations dependence on pH and temperature the influence of homogeneous or heterogeneous reactor operation in discontin-... 

Figure 1.4. Flow chart sheet of the strategy of bioprocess kinetic analysis for different process situations stationary/instationary, homogeneous/heterogeneous, differential/ integral, and true dynamic/balanced (frozen) reactor operation, rds, rate-determining step qss, quasi-steady-state, (From Moser, A. 1983.)...

Another application of the principle of separation is the case of truly heterogeneous processes (see Sects. 4.5, 6.6, and 6.7). Here, cases of external and internal transport limitation of a bioprocess must be distinguished from the case where the physical transport may be enhanced by the biological reaction. A simplified treatment in all these cases is possible through introduction of the concept of efficiency defined by... 

Pseudokinetic phenomena become evident only when process kinetic analysis is carried out with mathematical models. Most bioprocesses are basically heterogeneous systems. Generally, pseudohomogeneous rates measured in L phase analyses are used, because they are thought to reflect directly the intrinsic reaction rate of metabolism in the solid phase (biomass). Even under steady-state conditions, however, this assumption is not necessarily valid. 

Recently, the application of fluidized beds to bioprocessing stimulated the modeling of FBBRs. In this complex case, however, models of the hydraulics must be combined with a model of biofilm kinetics, including mass transport-affected substrate conversion. This truly heterogeneous case of reactor operation will be presented here. 

Yue CJ, Zhong JJ (2008) Manipulation of ginsenoside heterogeneity of Panax notoginseng cells in flask and bioreactor cultivations with addition of phenobarbital. Bioprocess Biosyst Eng 31(2) 95-100... 

Delvigne, F. and Gofim, P. (2014) Microbial heterogeneity affects bioprocess robustness dynamic single-cell analysis contributes to understanding of microbial populations. Biotechnol. J, 9 (1), 61-72. 

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