Membrane technology and biocatalysis

Purpose and goal

The aim of the project was to evaluate possibilities to achieve process improvements in biocatalytic conversion using membrane technology. Improvements can be foreseen in cases when the following problems appear: substrate inhibition, product inhibition and unfavourable equilibrium position. Transaminase catalyzed synthesis of a chiral amine was chosen for the studies since this is a conversion of large industrial interest because chiral amines are important building blocks of pharmaceuticals. Considerable improvements in reaction rate and yield were achieved.

Results and expected effects

Process improvements in reactions catalyzed be transaminases were quantified. Because the enzymatically produced amine was extracted through a membrane to a phase with low pH, product inhibition was minimized and the equilibrium position was shifted. This caused an increase in reaction rate and yield. The effects were so large and valuable that a patent application on the methodology was submitted.

Approach and implementation

Transaminase catalyzed synthesis of chiral amines was shown to be a suitable system to demonstrate the advantages of the novel membrane technology. Product inhibition and unfavourable equilibrium position normally limit the reaction rate and yield of the produced amine, but selective extraction of the amine via the membrane to another phase solved these problems. Balancing the composition of the phases on either side of the membrane, as well as the surface size and properties of the membrane, made it possible to control the process efficiently.