Cereals pp 63-67 | Cite as

On-Line Monitoring of Enzymatic Bioprocesses by Microdialysis Sampling, Anion Exchange Chromatography, and Integrated Pulsed Electrochemical Detection

  • Nelson Torto
  • Lo Gorton
  • György Marko-Varga
  • Thomas Laurell
Chapter

Abstract

Microdialysis sampling coupled to column liquid chromatography with integrated pulsed electrochemical detection (IPED) has been shown to be a hyphenation of techniques well suited for the analysis of oligomeric carbohydrates in a continuously changing matrix due to biological activity (Torto et al, 1995). Microdialysis provides a simultaneous sampling and sample clean-up step. Proper choice of a microdialysis membrane with known characteristics, e.g. molecular mass cut-off, porosity and sterilisability ensures enhanced performance of the technique in a crude medium, as it does not perturb the reaction under investigation. Only small amounts of the hydrolysis products (carbohydrates) are removed. Carbohydrates are separated in their enolate form at high pH, eliminating the need for pre- or post-column derivatisation. The chromatographic separation facilitates data evaluation, as carbohydrates are oxidised at the same potential during detection by IPED (Johnson et al, 1992). The purpose of this investigation was to develop an analytical system that could be used to sty dy a liquefaction step during the hydrolysis of wheat starch in a fermentation process where glucose is the substrate (see Chapter 8). System development was carried out using soluble starch according to Zulkowsky.

Keywords

Degree Ofpolymerisation Extraction Fraction Microdialysis Probe Wheat Starch Microdialysis Sampling 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • Nelson Torto
    • 1
  • Lo Gorton
    • 2
  • György Marko-Varga
    • 2
  • Thomas Laurell
    • 3
  1. 1.Department of ChemistryUniversity of BotswanaGaboroneBotswana
  2. 2.Department of Analytical Chemistry, Center for Chemistry and Chemical EngineeringUniversity of LundLundSweden
  3. 3.Department of Electrical MeasurementsUniversity of LundLundSweden

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