ESEL Paper Review_20140324

By Hong Guo

Mail: hongguo@gist.ac.kr

Phone: (+82) (0)10 82276568

1, Title and Author

Title: Unstructured Model for L-Lysine Fermentation under Controlled Dissolved

Journal: Biotechnology

Authors:

Semsi Ensari*,†, Joon Ha‡ , and Henry C.Lim‡

Biotechnology Development, Schering-Plough Research Institute, 1011 Morris Avenue, U-14-2-20,Union, New Jersey 07083

Department of Chemical Engineering and Materials Science, University of

California-Irvine, Irvine, California 92697

2. Summary of Paper

? In this study, an unstructured model was developed for batch cultivation of Corynebacterium lactofermentum under controlled dissolved oxygen.

? The specific rates developed using batch culture data are adapted for fed-batch cultures and an intuitive optimization technique is used to show through simulation superiority of fed-batch operation

3. Results

? The overall cell yield drops significantly at high initial glucose concentrations, while the overall product yield appears total level off .

? The productivity of the continuous culture is 60% higher than the batch culture, and both the cell and the product yields are comparable to batch data.

? While low productivity is inherent in comparing batch against continuous cultures, batch culture produced a higher amount of product due to almost complete consumption of residual substrate.

? Fed-Batch Culture.

? Finally, to simulate fed-batch culture, the initial conditions were set to 0.1 g/L cell, optimal substrate concentration, S* ) 17.1 g/L, no product, and a bioreactor volume of 3 L. The feed substrate concentration, SF, final bioreactor volume, Vf, and maximum flow rate, Fmax, were set to 400 g/L, 10 L and 360 mL/h, respectively.

? The simulations were stopped when the substrate concentration was reduced to less than 1 g/L. Total cultivation times for batch and fed-batch cultivations were found to be 284 and 243 h, respectively.

? In comparison to batch culture with a high initial substrate concentration, fed-batch culture with a high initial substrate concentration, fed-batch culture displays a rapid increases in cell and product concentration.

? Compared to batch culture, the overall cell yield decreases and the product yield increases.

4. Contribution:

This research would be fully studied and applied to the research of reactor modelling, which is related to the our current class- Environmental Systems Engineering.

5. Contact (Mail address): semsi.ensari@spcorp.com.