Use of hydrophilic ionic liquids in a two-phase system to improve Mung bean epoxide hydrolases-mediated asymmetric hydrolysis of styrene oxide

J Biotechnol. 2012 Dec 31;162(2-3):183-90. doi: 10.1016/j.jbiotec.2012.09.006. Epub 2012 Sep 17.

Abstract

A comparative study was made of Mung bean epoxide hydrolases-catalyzed asymmetric hydrolysis of styrene oxide to (R)-1-phenyl-1,2-ethanediol in an n-hexane/buffer biphasic system containing various hydrophilic ionic liquids (ILs). Compared to the n-hexane/buffer biphasic system alone, addition of a small amount of hydrophilic ILs reduced the amount of non-enzymatic hydrolysis, and improved the reaction rate by up to 22%. The ILs with cation containing an alkanol group, namely [C(2)OHMIM][BF(4)] and [C(2)OHMIM][TfO], and the choline amino acid ILs [Ch][Arg] and [Ch][Pro] were found to be the most suitable co-solvents for the reaction, owing to their good biocompatibility with the enzyme, which led to high initial rates (0.99-1.25 μmol/min) and high product e.e.s (95%). When substrate concentration was around 30 mM, where optimal performance was observed with the IL-containing systems, the product e.e. was improved from 90% without ILs to ≥95% in the presence of ILs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biotechnology
  • Epoxide Hydrolases / chemistry*
  • Epoxide Hydrolases / isolation & purification
  • Epoxide Hydrolases / metabolism
  • Epoxy Compounds / chemistry*
  • Epoxy Compounds / metabolism
  • Fabaceae / chemistry
  • Fabaceae / enzymology*
  • Hydrogen-Ion Concentration
  • Hydrolysis / drug effects
  • Hydrophobic and Hydrophilic Interactions
  • Imidazoles / chemistry
  • Imidazoles / pharmacology
  • Ionic Liquids / chemistry*
  • Ionic Liquids / pharmacology
  • Temperature

Substances

  • Epoxy Compounds
  • Imidazoles
  • Ionic Liquids
  • styrene oxide
  • Epoxide Hydrolases