Efficient biocatalytic synthesis of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol by a newly isolated Trichoderma asperellum ZJPH0810 using dual cosubstrate: ethanol and glycerol

Appl Microbiol Biotechnol. 2013 Aug;97(15):6685-92. doi: 10.1007/s00253-013-4973-z. Epub 2013 May 23.

Abstract

(R)-[3,5-bis(trifluoromethyl)phenyl] ethanol is a crucial intermediate for the synthesis of Aprepitant. An efficient biocatalytic process for (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol was developed via the asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone, catalyzed by whole cells of newly isolated Trichoderma asperellum ZJPH0810 using ethanol and glycerol as dual cosubstrate for cofactor recycling. A fungal strain ZJPH0810, showing asymmetric biocatalytic activity of 3,5-bis(trifluoromethyl) acetophenone to its corresponding (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol, was isolated from a soil sample. Based on its morphological and physiological characteristics and internal transcribed spacer sequence, this isolate was identified as T. asperellum ZJPH0810, which afforded an NADH-dependent (R)-stereospecific carbonyl reductase and was a promising biocatalyst for the synthesis of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol. Some key reaction parameters involved in the bioreduction catalyzed by T. asperellum ZJPH0810 were subsequently optimized. The effectiveness of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol production was significantly enhanced by employing a novel dual cosubstrate-coupled system for cofactor recycling. The established efficient bioreduction system contained 50 mM of 3,5-bis(trifluoromethyl) acetophenone and 60 g l(-1) of resting cells, employing ethanol (6.0 %, v/v) and glycerol (0.5 %, v/v) as dual cosubstrate. The bioreduction was performed in distilled water medium, at 30 °C and 200 rpm. Under the above conditions, a best yield of 93.4 % was obtained, which is nearly a 3.5-fold increase in contrast to no addition of cosubstrate. The ee value of the product reached above 98 %. This biocatalytic process shows great potential in the production of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol, a valuable chiral building block in the pharmaceutical industry.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Benzyl Alcohols / metabolism*
  • Biocatalysis
  • DNA Primers
  • Ethanol / metabolism*
  • Glycerol / metabolism*
  • NAD / metabolism
  • Phylogeny
  • Polymerase Chain Reaction
  • Substrate Specificity
  • Trichoderma / classification
  • Trichoderma / metabolism*

Substances

  • Benzyl Alcohols
  • DNA Primers
  • NAD
  • Ethanol
  • Glycerol