Applied Biochemistry and Biotechnology

, Volume 28, Issue 1, pp 527–538 | Cite as

Enzymatic hydrolysis of starch in a fixed-bed pulsed-flow reactor

  • A. Sanromán
  • R. Chamy
  • M. J. Núñez
  • J. M. Lema
Session 4 Bioengineering Research


One of the most important problems in the design and operation of fixed-bed biological reactors is the control of the process rate by mass-transfer limitations. In order to overcome this problem, a new technology, based on the use of pulsed reactors, was developed. A new type of pulsing device, giving a see-saw-type of disturbance, was assayed. To quantify the possible improvement obtained, we have chosen as an example the hydrolysis of concentrated starch solutions by glucoamylase (fromAspergillus niger) immobilized on chitin slabs. The reactor has an internal diameter of 50 mm and a bed height of 200 mm. Temperature was controlled at 25°C, and the working hydraulic retention times were from 0.29 to 1.8 h. The results revealed that pulsation helps to lessen the diffusional difficulties, since the maximum reaction velocity increased 10%. Additional improvements, up to 20% in some cases, are achieved by recycling a part of partially converted feed.

Index Entries

Pulsed flow packed-bed starch hydrolysis immobilized glucoamylase chitin 



mean residence time h

So, S

initial and final substrate concentration g/L


hydrolysis rate g/L.min


maximum reaction rate g/L-min


Michaelis constant g/L


recirculation rate = return flow/out flow


time h


normalized time


axial dispersion coefficient m2/s


number of tanks in series


normalized tracer response to a pulse input


apparent viscosity kg/m.s

- dv/dr

velocity gradient s-1


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  1. 1.
    Srinikethan, G., Prabhakar, A., and Varma, Y. B. G. (1987),Bioprocess Eng. 2, 161–168.CrossRefGoogle Scholar
  2. 2.
    Finnigan, S. M. and Howell, J. A. (1989),Chem. Eng. Res. Des. 67, 278–282.Google Scholar
  3. 3.
    Hwang, K.-Y. and Brauer, H. (1987),Biotech Forum 4, 3, 118–130.Google Scholar
  4. 4.
    Etzold, M. and Stadlbauer, E. A. (1990),Bioprocess Eng. 5, 7–12.CrossRefGoogle Scholar
  5. 5.
    Hamamci, H. and Ryu, D. D. Y. (1988),Appl. Microbiol. Biotechnol. 28, 515–519.CrossRefGoogle Scholar
  6. 6.
    Ghommidh, C, Navarro, J. M, and Durand, G. (1982),Biotechnol. Bioeng. 24, 605–617.CrossRefGoogle Scholar
  7. 7.
    Baird, M. H., Vijayan, S., Rama Rao, N. V., and Rohatgi, A. (1989),Can. J. Chem. Eng. 67, 787–800.CrossRefGoogle Scholar
  8. 8.
    Murthy, V. V. P. S., Ramachandran, K. B., and Ghose, T. K. (1989),Process Biochem. 4, 77–83.Google Scholar
  9. 9.
    Navarro, J. M. and Goma, G. (1980),Nouveau dispositif de Mise en Oeuvre des Micro-Organismes. Brevet d’invention n°78 28572, Institut National de la Propriété Industrielle. Paris.Google Scholar
  10. 10.
    Bouzas, S., Casares, J. J., and Lema, J. M. (1988), Ingeniería Química234, 209–214.Google Scholar
  11. 11.
    Bouzas, S., Casares, J. J., and Lema, J. M. (1988), Ingenieria Quimica237, 115–120.Google Scholar
  12. 12.
    Bernfeld, D. P. (1951),Adv. Enzymol. 12, 379–427.Google Scholar
  13. 13.
    Bunday, B. D. (1984),Basic Optimization Methods (E. Arnold Pu, London).Google Scholar
  14. 14.
    Stanley, W. L., Watters, G. G., Kelley, S. H., and Olson, A. C. (1978),Biotechnol. Bioeng. 20, 135–140.CrossRefGoogle Scholar
  15. 15.
    Synowiecki, J., Sikorski, E., Naczk, M., and Piotrzkowska, H. (1982),Biotechnol. Bioeng. 24, 1871–1876.CrossRefGoogle Scholar
  16. 16.
    Miranda, M., Murado, M. A., Sanromán, A., and Lema, J. M.Enzyme Microb. Technol. (in press).Google Scholar

Copyright information

© Humana Press Inc. 1991

Authors and Affiliations

  • A. Sanromán
    • 1
  • R. Chamy
    • 1
  • M. J. Núñez
    • 1
  • J. M. Lema
    • 1
  1. 1.Department of Chemical Engineering, Avda, Ciencias s/nUniversity of Santiago de CompostelaSpain

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