Abstract
The thermal stability of purified acid phosphatase from the germinating seedlings of
(Jangli halon) was investigated by studying the impact of various thermodynamic parameters [
,
, Δ
° (enthalpy change), Δ
° (free energy change), and Δ
° (entropy change)] of heat treatment in the temperature range of 55-75 °C. The thermal denaturation of acid phosphatase, assessed by loss in activity, was evidently followed by first-order kinetics, which varies with time and yield during the process of denaturation. The half-life of the enzyme was 693 min at 55 °C. The
(activation energy of denaturation) was calculated by the Arrhenius plot (30 kcal mol
), and the
-value was 17.3 °C. The various thermodynamic parameters studied were as follows: Δ
°, the change in enthalpy of inactivation, was 121.93 kJ mol
at 55 °C; Δ
°, the change in free energy of inactivation, was 110.65 kJ mol
at 55 °C; and Δ
°, the change in entropy of inactivation, was 34.39 J mol
k
at 55 °C. This suggests that acid phosphatase activity is thermostable to long heat treatment up to 60 °C.