PhD Defence by Jingyu Wang
“Kinetic Stability of Redox Enzymes at Gas Liquid Interfaces”
Principal supervisor
Professor John Woodley,
DTU Chemical Engineering
Co-supervisor
Professor Manuel Pinelo,
DTU Chemical Engineering
Examiners
Professor Günther Peters (Chairman )
DTU Chemistry
Professor Per Berglund
KTH Stockholm, Sweden
Associated Professor Caroline Paul
TU Delft, The Netherlands
Chairperson at defence
Associated Professor Ulrich Krühne
DTU Chemical Engineering
The defence will be held virtually. If you wish to attend the defense virtually you can sign up by sending an e mail to Ulrich Krühne, please see contact.
14 February at 12:00 at the latest. You will receive an invitation to join the virtual defense.
Popular Summary
Enzymatic oxidation is currently receiving great interest as a tool in organic synthesis, in
particular in the synthesis of active pharmaceutical intermediates (APIs), using asymmetric
synthesis as well as chiral resolution because of the high region-, enantio-, and stereo
selectivity of biocatalyst. For biocatalytic oxidation, O2 readily available in the air is the
promising oxidant with economic and environmental sustainability. However, ensuring efficient
O2 supply is crucial due to the low solubility of O2 in water solution. Increasing the ratio of gasliquid
interface to liquid by gas bubbling will effectively enhance O2 mass transfer and therefore
promote the oxidation efficiency, and following by the problem of enzyme stability exposure to
gas-liquid interface.
Generally, enzyme exposed to gas-liquid interface will lead to enzyme unfolding and
aggregation, resulting in enzyme deactivation. Furthermore, selecting the appropriate O2
concentration (ranging from 0% to 100%) is vital for this process, because excessively high O2
levels can directly lead to over oxidation of the enzyme amino acid residue and following
activity lose. Conversely, low O2 concentration will limit O2 transfer rate and imped the
biocatalytic oxidation reaction. The structure of the enzyme and the composition of gas are
also related to the stability of the enzyme. Therefore, the choice of O2 concentration and also
screen for more stable enzyme are critical issues for oxidase. The mentioned above has
indeed effect on the stability of oxidases and further study should be carried on to find the
relationship which has a significant impact on the large-scale use of biocatalysts.