Efficient phase separation and product recovery in organic‐aqueous bioprocessing using supercritical carbon dioxide
Biphasic hydrocarbon functionalizations catalyzed by recombinant microorganisms have been shown to be one of the most promising approaches for replacing common chemical synthesis routes on an industrial scale. However, the formation of stable emulsions complicates downstream processing, especially phase separation. This fact has turned out to be a major hurdle for industrial implementation. To overcome this limitation, we used supercritical carbon dioxide (scCO2) for both phase separation and product purification. The stable emulsion, originating from a stereospecific epoxidation of styrene to (S)‐styrene oxide, a reaction catalyzed by recombinant Escherichia coli, could be destabilized efficiently and irreversibly, enabling complete phase separation within minutes. By further use of scCO2 as extraction agent, the product (S)‐styrene oxide could be obtained with a purity of 81% (w/w) in one single extraction step. By combining phase separation and product purification using scCO2, the number of necessary workup steps can be reduced to one. This efficient and easy to use technique is generally applicable for the workup of biphasic biocatalytic hydrocarbon functionalizations and enables a cost effective downstream processing even on a large scale. Biotechnol. Bioeng. 2010;107:642–651. © 2010 Wiley Periodicals, Inc.
Document Type: Research Article
Affiliations: 1: Laboratory of Thermodynamics, TU Dortmund University, D-44227 Dortmund, Germany; telephone: +49-231-755-2635;, Fax: +49-231-755-2075 2: Laboratory of Chemical Biotechnology, TU Dortmund University, D-44227 Dortmund, Germany; telephone: +49-231-755-7384;, Fax: +49-231-755-7382
Publication date: November 1, 2010