Optimal fed‐batch control of induced foreign protein production by recombinant bacteria

Abstract

Optimal control strategies for maximizing the production of induced foreign protein by recombinant bacteria were sought by the optimal control theory. Nutrient and inducer feeding rates were selected as key control variables. Since the problem is linear in the control variables, the optimal control is bang-bang or singular. Singular solutions are shown to exist. The optimal control theory showed that the specific growth rate with respect to nutrient concentration must be kept in its maximum phase and that there exist both a cell growth period and a protein production period. The optimal control theory calculates exactly the growth and production periods. The glucose concentration is controlled along a singular arc to give a maximum specific growth rate. The inducer level is controlled along a separate singular arc.

Optimization of fed-batch fermentation processes using the Backtracking Search Algorithm

“…The second case study involves induced foreign protein production by recombinant bacteria, 325 firstly proposed by Lee and Ramirez (1994). The problem was later modified by Tholudur and 326 Ramirez ( (17) 333 The PI is defined as: 339…”

Control of fermenters – a review

“…The optimal control policy for maximization of secreted protein in a fed-batch reactor was found to consist of multiple singular arcs and an iterative strategy was developed to ®nd the optimal transitions between such arcs on the basis of minimum principle of Pontryagin [62]. Lee and Ramirez [63] derived singular control solutions for maximizing production of induced foreign protein by recombinant bacteria using nutrient and inducer feeding rates as control variables and compared the performance with bang-bang control solution and concluded that for the example considered, best bang-bang control is nearly equivalent to the optimal singular control.…”

Dynamic Optimization in Chemical Processes Using Region Reduction Strategy and Control Vector Parameterization with an Ant Colony Optimization Algorithm

“…The main disadvantage of this method is that the algorithm may converge to local minima in many cases [3]. In addition, Lee and Ramirez [5] found an analytical solution for industrial foreign protein production by recombinant bacteria. Their problem had two control variables, and the algorithm was difficult to implement.…”