Catalytic and thermodynamic properties of a tannase produced by Aspergillus niger GH1 grown on polyurethane foam

Appl Biochem Biotechnol. 2011 Nov;165(5-6):1141-51. doi: 10.1007/s12010-011-9331-y. Epub 2011 Aug 12.

Abstract

Tannase is an inducible enzyme with important applications in the food and pharmaceutical industries. This enzyme was produced by the fungus Aspergillus niger GH1 under solid-state fermentation using polyurethane foam as solid support and tannic acid as sole carbon source and tannase inducer. Physicochemical properties of A. niger tannase were characterized, and the kinetic and thermodynamics parameters on methyl gallate hydrolysis were evaluated. The enzyme was stable in a pH range of 2-8 and a functional temperature range of 25-65 °C. The highest k(cat) value was 2,611.10 s(-1) at 65 °C. Tannase had more affinity for methyl gallate at 45 °C with a K(M) value of 1.82 mM and an efficiency of hydrolysis (k(cat)/K(M)) of 330.01 s(-1) mM(-1). The lowest E(a) value was found to be 21.38 kJ/mol at 4.4 mM of methyl gallate. The lowest free energy of Gibbs (ΔG) and enthalpy (ΔH) were found to be 64.86 and 18.56 kJ/mol, respectively. Entropy (ΔS) was -0.22 kJ/mol K. Results suggest that the A. niger GH1 tannase is an attractive enzyme for industrial applications due its catalytic and thermodynamical properties.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aspergillus niger / enzymology*
  • Aspergillus niger / growth & development
  • Batch Cell Culture Techniques / instrumentation
  • Biocatalysis
  • Carboxylic Ester Hydrolases / chemistry*
  • Carboxylic Ester Hydrolases / metabolism
  • Enzyme Stability
  • Fermentation
  • Fungal Proteins / chemistry*
  • Fungal Proteins / metabolism
  • Hydrogen-Ion Concentration
  • Kinetics
  • Polyurethanes / analysis

Substances

  • Fungal Proteins
  • Polyurethanes
  • polyurethane foam
  • Carboxylic Ester Hydrolases
  • tannase