Biphasic whole-cell biocatalysis is a promising alternative to chemical synthesis routes especially for stereo-selective products. These reaction systems allow nearly quantitative conversion, high concentrations of apolar products and no need of co-factor addition, what qualifies them for industrial applications. However these systems often suffer from the formation of stable emulsions that cannot be separated by common unit operations. Within this work, thermodynamics based approaches for the downstream processing of these reaction systems are investigated and applicable concepts developed.
Description:
Emulsions resulting from biphasic whole-cell biocatalysis are stabilized in parallel by several mechanisms due to their complex composition. The stability is thereby based on the presence of many different components like cells, cell debris and other surface active compounds. Based on the work of Brandenbusch [1], who showed a supercritical CO2 assisted downstream processing for a bio reaction system for the first time, the underlying stabilization mechanisms are investigated. Additionally to real systems, model emulsions containing functionalized particles are investigated to gain general thermodynamic data on the phase separation of emulsions resulting from whole-cell biotechnological processes.
[1] Brandenbusch, C.:
"Downstream processing in biphasic biocatalysis by means of scCO2"
Dr. Hut (2012), München, ISBN 978-3-8439-0314-1