Characterization of Bioimprinted Tannase and Its Kinetic and Thermodynamics Properties in Synthesis of Propyl Gallate by Transesterification in Anhydrous Medium

Abstract

Tannase has been extensively applied to synthesize gallic acid esters. Bioimprinting technique can evidently enhance transesterification-catalyzing performance of tannase. In order to promote the practical utilization of the modified tannase, a few enzymatic characteristics of the enzyme and its kinetic and thermodynamics properties in synthesis of propyl gallate by transesterification in anhydrous medium have been studied. The investigations of pH and temperature found that the imprinted tannase holds an optimum activity at pH 5.0 and 40 °C. On the other hand, the bioimprinting technique has a profound enhancing effect on the adapted tannase in substrate affinity and thermostability. The kinetic and thermodynamic analyses showed that the modified tannase has a longer half-time of 1,710 h at 40 °C; the kinetic constants, the activation energy of reversible thermal inactivation, and the activation energy of irreversible thermal inactivation, respectively, are 0.054 mM, 17.35 kJ mol(-1), and 85.54 kJ mol(-1) with tannic acid as a substrate at 40 °C; the free energy of Gibbs (ΔG) and enthalpy (ΔH) were found to be 97.1 and 82.9 kJ mol(-1) separately under the same conditions.

Structural characterization, catalytic, kinetic and thermodynamic properties of Aspergillus oryzae tannase

“…On the contrary, cold-active enzyme showed that its thermolability is entropically driven [33]. The energy of activation E a(d) for irreversible thermal inactivation of A. oryzae tannase was (163.37 kJ mol −1 , calculated from Fig 9) was higher than the previous recorded values for other tannases [34]. These results indicate that more energy is required to inactivate the enzyme and hence implied to be more thermostable.…”