Biocatalytic production of chiral epichlorohydrin in organic solvents
1Department of Chemical Technology, College of Engineering, Seoul National University, Seoul 151-742, Korea.
Abstract:
Enantioselective hydrolysis of racemic epichlorohydrin was accomplished for the production of enantiopure epichlorohydrin using the whole cells of an isolated Aspergillus niger spps. To overcome the spontaneous chemical degradation of epichlorohydrin that occurs in aqueous buffer, organic solvents were employed in the reaction medium. The enantioselectivity was highly dependent on the solvent structure, water content of the medium, and the initial epichlorohydrin concentration. (S)-epichlorohydrin could be obtained from its racemates (60 mM) with an optical purity of 100% enantiomeric excess (ee) and 20% yield in cyclohexane supplemented with 2.0% (v/v) water.
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