Bioreactor control

Observer and filtering techniques Anaerobic bioreactor control [86]... 

Several interesting parameter-control models or systems have been reported in recent years. These are a five-state mathematical model for temperature control by Bailey and Nicholson [106], a mathematical-model description of the phenomenon of light absorption of Coffea arabica suspension cell cultures in a photo-culture vessel by Kurata and Furusaki [107], and a bioreactor control system for controlling dissolved concentrations of both 02 and C02 simultaneously by Smith et al. [108]. 

Identifying an environment that avoids induction of undesired enzymes and repression of desired ones and implementing bioreactor control systems that maintain these desired conditions in a bioprocess are subjects of future importance. For example, accumulation of a product in the cell environment can often repress synthesis of some of the enzymes required for production of that compound. Product repression and inhibition phenomena have motivated special interest recently in combined bioprocessing operations which accomplish separation simultaneously with bioreaction. By continuously removing a product that inhibits its own synthesis, production of that material is improved. Development of new selective membranes and other process strategies for accomplishing these separations is an important area for future research. 

II. BRIEF OVERVIEW OF CURRENT CONTROL METHODS A. Bioreactor Control... 

A key problem in bioreactor control is the difficulty in obtaining reliable sensors and consequently of reliable on-line process information. Demands for product consistency and process productivity produce requirements for more process information.13 Especially in the case of fermentors, rapid, accurate on-line measurement of process variables is often a complex task. As a result, much research effort has focused on methods for quantitatively estimating compositions within reactors and on using model-based control techniques. 

Glacken MW (1991) Bioreactor control and optimization. In Ho CS Wang DIC (eds) Animal Cell Bioreactors, pp. 373-404. Butterworth-Heinemann, Oxford. 

Schugerl K (1988) Measurement and bioreactor control. In Durand G, Bobichon L Florent J (eds). Proceedings of 8th International Biotechnology Symposium, Paris, 1988, pp. 547-562. Societe Frangaise de Microbiologie, Paris, Cedex 15. 

The measurement of analyte concentration is a critical part of successful bioreactor monitoring. Although strategies exist for measuring the majority of relevant analytes, industrial online bioreactor control is carried out primarily by measurement and control of temperature, pH, d02, CO2, and, in some cases, cell density. This is because the available technology cannot be easily and inexpensively adapted to measure the analyte in an aseptic manner and measurement is not often achieved in real time so that online control is challenging. Biosensors for a variety of applications for... 

The long range goal continues to be to relate the metabolic activities of cell cultures to bioreactor control. Early studies focused on measuring the respiration quotient and rate of ammonia addition for pH control and combining these measurements with elemental and microscopic balances to predict behavior of batch, fed-batch, and continuous yeast cultures. Cybernetic models continue to be studied with the goal of using these models to control bioreactors. ... 

Reddy, G.P, and Chidambaram, M. (1995), Near-optimalproductivity control of a continuous bioreactor, / Control Theory and Applications, 142(6) 633-637. 

AdhaT, AyqhD, puuC, dhaB123, gdrAB 5-1 fed-batch bioreactor controlled DO 5% >28.0... 

Mahadevan, R., S. K. Agrawal, and F. J. Doyle III, Differential Flatness Based Nonlinear Predictive Control of Fed-Batch Bioreactors, Control Eng. Prac., 9, 889 (2001). 

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