Four peroxidase isozymes from horseradish roots (isozymes A, B, C and D) mere isolated by chromatography and were thermally inactivated at 70∼97℃ and pH 7.0.
The four isozymes had different inactivation rates and the inactivation of each isozymes did not follow first order kinetics. D values of isozymes A, B, C, D and crude enzyme were 594 s, 1850 s, 2050 s, 78 s, 130 s and z values were 24.0℃, 12.5℃, 18.0℃, 23.7℃ and 24.0℃, respectively. Sephadex gel chromatogram of the thermally treated isozyme C indicated that the shape and molecular weight of the native isozyme changed during inactivation.
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