Excess Thermodynamical Studies of Dextrin with alpha-Amylase

Ultrasonic velocity (U), density (rho), and viscosity (eta) measurements have been carried out in three ternary mixtures of dextrin with alpha-amylase in aqueous medium at 298.15 K. The experimental data have been used to calculate some derived parameters such as acoustical impedance (Z), relative association (Ra), Rao's costant (R), Wada's constant (W), relaxation time (tau), relaxation amplitude (alpha/f(2)), relaxation strength (r), and some excess thermodynamical properties like excess adiabatic compressibility (beta(E)), excess free length (L-f(E)) excess free volume (V-f(E)), excess internal pressure (pi(E)(i)), and excess acoustical impedance (Z(E)). The above parameters have been evaluated and discussed in light of intermolecular interactions in these mixtures.