Studies on thermodynamics and kinetics of thermo-inactivation of xylanase from salivary glands of Macrotermes subhyalinus little soldier

Abstract

The effect of heat treatment on the activity of xylanase, from salivary glands of Macrotermes subhyalinus little soldier was studied over a temperature range of 50 to 70 °C using mathematical analysis of the kinetic and thermodynamic parameters for the thermo-inactivation of the enzyme. Denaturation of the enzyme, measured by loss in activity, could be described as a first-order model, with k-values between 0.005 and 0.0217. D-values decreased with increasing temperature, indicating faster inactivation of the enzyme at higher temperatures. Results suggested that xylanase is the rmostable with a Z-value of 22.57, Ea of 92.68 kJ mol -1 . Thermodynamic parameters were also calculated. The Gibbs free energy (ΔG), values range from 109.36 to 110.27 kJ/mol for the enzyme. These kinetic data can be used to allow the adequate utilization of the xylanase of Macrotermes subhyalinus little soldier in the food industry and technology applications.