Mathematisch-Naturwissenschaftliche Fakultät

Institut für Chemie

Fachgebiet: Chemical Engineering

Betreuer: Prof. Dr. Udo Kragl

Jan von Langermann und Erlencamp
(e-mail: )

Medium-engineering for enzymatic reaction at different examples of hydroxynitrile lyases and alcohol dehydrogenases

This cumulative doctoral thesis deals with the concept ‘medium engineering’ for enzymatic reactions. The main research objective was the overcoming of kinetic and thermodynamic limitation by using organic solvents. Different concepts with alcohol dehydrogenase- and hydroxynitrile lyase-catalysed were investigated and the practicability was discussed.

It was shown that water miscible organic solvents are feasible agents to influence kinetic parameters. As an example, the substrate inhibition at an alcohol dehydrogenase catalysed reduction of butan-2-on was reduced.

Water-immiscible organic solvents are suitable for the overcoming of thermodynamic limitations. By the usage of a two-phase system the non-enzymatic cyanohydrin synthesis was noticeable reduced. Additionally, with a borderlice case of this reaction system the thermodynamically limited acetophenone cyanohydrin synthesis was enhanced from 2 to 36 %.