Alcohol dehydrogenase stabilization by additives under industrially relevant reaction conditions

Abstract Alcohol dehydrogenases form one of the most important enzyme classes for the synthesis of chiral hydroxyl-compounds. High solvent concentrations may improve the efficiency of biocatalytic ADH reactions but, however, turned out to damage most enzymes. In order to overcome the damage caused to these enzymes, this work describes the stabilization of five different alcohol dehydrogenases under very high solvent concentrations (up to 90% of the reaction volume). The reductive conversion of the ketone substrate into the corresponding alcohol was increased up to sevenfold by pre-incubating the enzymes with specific stabilizers. This technique is highly efficient and additionally facile as no prior immobilization, polymerization or deposition treatment is necessary. It was revealed that each ADH gained an optimal stabilization effect by one specific stabilizer and appropriate concentration. Furthermore, the results obtained on laboratory scale were transferred successfully to 4000 mL scale to verify the applicability of this technique for industrial use.