A novel extracellular β-glucosidase from Trichosporon asahii: yield prediction, evaluation and application for aroma enhancement of Cabernet Sauvignon

J Food Sci. 2012 Aug;77(8):M505-15. doi: 10.1111/j.1750-3841.2012.02705.x. Epub 2012 Jul 18.

Abstract

The production and application of novel β-glucosidase from Trichosporon asahii were studied. The β-glucosidase yield was improved by response surface methodology, and the optimal media constituents were determined to be dextrin 4.67% (w/v), yeast extract 2.99% (w/v), MgSO(4) 0.01% (w/v), and K(2) HPO(4) 0.02% (w/v). As a result, β-glucosidase production was enhanced from 123.72 to 215.66 U/L. The effects of different enological factors on the activity of β-glucosidases from T. asahii were investigated in comparison to commercial enzymes. β-Glucosidase from T. asahii was activated in the presence of sugars in the range from 10% to 40% (w/v), with the exception of glucose (slight inhibition), and retained higher relative activities than commercial enzymes under the same conditions. In addition, ethanol, in concentrations between 5% and 20% (v/v), also increased the β-glucosidase activity. Although the β-glucosidase activity decreased with decreasing pH, the residual activity of T. asahii was still above 50% at the average wine pH (pH 3.5). Due to these properties, extracellular β-glucosidase from T. asahii exhibited a better ability than commercial enzymes in hydrolyzing aromatic precursors that remained in young finished wine. The excellent performs of this β-glucosidase in wine aroma enhancement and sensory evaluation indicated that the β-glucosidase has a potential application to individuate suitable preparations that can complement and optimize grape or wine quality during the winemaking process or in the final wine.

Practical application: The present study demonstrated the usefulness of response surface methodology based on the central composite design for yield enhancement of β-glucosidase from T. asahii. The investigation of the primary characteristics of the enzyme and its application in young red wine suggested that the β-glucosidase from T. asahii can provide more impetus for aroma improvement in the future.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Culture Media / chemistry
  • Ethanol / chemistry
  • Food Handling / methods
  • Food Microbiology*
  • Glucose / chemistry
  • Humans
  • Hydrogen-Ion Concentration
  • Odorants / analysis
  • Smell
  • Trichosporon / enzymology*
  • Trichosporon / growth & development
  • Vitis / microbiology
  • Volatile Organic Compounds / chemistry
  • Wine / analysis
  • Wine / microbiology*
  • beta-Glucosidase / analysis
  • beta-Glucosidase / biosynthesis*

Substances

  • Culture Media
  • Volatile Organic Compounds
  • Ethanol
  • beta-Glucosidase
  • Glucose