Model Development for Lactic Acid Fermentation and Parameter Optimization Using Genetic Algorithm

  • LIN , JIAN-QIANG (State Key Lab of Microbial Technology, School of Life Science, Shandong University) ;
  • LEE, SANG-MOK (Department of Biological Engineering, ERC for Advanced Bioseparation Technology, Inha University) ;
  • KOO, YOON-MO (Department of Biological Engineering, ERC for Advanced Bioseparation Technology, Inha University)
  • Published : 2004.12.01

Abstract

An unstructured mathematical model is presented for lactic acid fermentation based on the energy balance. The proposed model reflects the energy metabolic state and then predicts the cell growth, lactic acid production, and glucose consumption rates by relating the above rates with the energy metabolic rate. Fermentation experiments were conducted under various initial lactic acid concentrations of 0, 30, 50, 70, and 90 g/l. Also, a genetic algorithm was used for further optimization of the model parameters and included the operations of coding, initialization, hybridization, mutation, decoding, fitness calculation, selection, and reproduction exerted on individuals (or chromosomes) in a population. The simulation results showed a good fit between the model prediction and the experimental data. The genetic algorithm proved to be useful for model parameter optimization, suggesting wider applications in the field of biological engineering.

Keywords

References

  1. Boonmee, M., N. Leksawasdi, W. Bridge, and P. L. Rogers. 2003. Batch and continuous culture of Lactococcus lactis NZ133: Experimental data and model development. Biochem. Eng. J. 14: 127-135
  2. Goldberg, D. E. 1989. Genetic Algorithm in Search, Optimization and Machine Learning. Addison Wesley, U.S.A
  3. Lin, J. Q., S. M. Lee, H. J. Lee, and Y. M. Koo. 2000. Modeling of typical microbial cell growth in batch culture. Biotechnol. Bioprocess Eng. 5: 382-385
  4. Luedeking, R. and E. L. Piret. 1959. A kinetic study of the lactic acid fermentation. J. Biochem. Microbiol. 1: 393-412
  5. Keller, A. K. and P. Gerhardt. 1975. Continuous lactic acid fermentation of whey to produce a ruminant feed supplement high in crude protein. Biotechnol. Bioeng. 17: 997-1018
  6. Kim, N.-J., I. S. Suh, B.-K. Hur, and C.-G. Lee. 2002. Simple monodimensional model for linear growth rate of photosynthetic microorganisms in flat-plate photobioreactors. J. Microbiol. Biotechnol. 12(6): 962-972
  7. Nielsen, J., K. Nikolajsen, and J. Villadsen. 1991. Structured modeling of a microbial system, part 1, 2. Biotechnol. Bioeng. 38: 1-10, 11-23
  8. Olmos-Dichara, A., F. Ampe, J. Uribelarrea, A. Pareilleux, and G. Goma. 1997. Growth and lactic acid production by Lactobacillus casei ssp. Rhamnosus in batch and membrane bioreactor. Biotechnol. Lett. 8: 709-714
  9. Suh, I. S. and S. B. Lee. 2003. Optimization of radiator position in an internally radiating photobioreactor: a model simulation study. J. Microbiol. Biotechnol. 13(5): 789-793
  10. Vickroy, T. B. 1985. Lactic acid, pp. 761-776. In: Blanch, H. W., Drew, S. and Wang, D. I. C. (eds.), The Practice of Biotechnology: Commodity Products. Pergamon Press, Elmsford, NY, U.S.A
  11. Wang, D., L. Gao, J. Q. Lin, Y. B. Qu, J. Q. Lin, and S. Y. Yu. 2002. Optimization of substrate feeding trajectory for fed-batch culture using genetic algorithm. Industr. Microbiol. 32: 40-43. (in Chinese)
  12. Youssef, C. B., V. Guillou, and A. Olmos-Dichara. 2000. Modeling and adaptive control strategy in a lactic acid fermentation process. Contr. Eng. Pract. 8: 1297-13