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Peroxidase from Jerusalem artichoke tubers, which might be related to browning reaction, was purified by ammonium sulfate precipitation, DEAE-cellulose and Sephacryl S-200 chromatography. The optimum pH of the purified peroxidase was 5.0 and relatively stable at pH 5.0∼6.0 using substrate of p-phenylenediamine and HZOZ. D-values for thermal inactivation at 60, 70 and 80℃ were 86, 45 and 33 sec, respectively. Activation energy was 4,111 J/mole. The enzyme showed the most sensitive specificity of substrate for p-phenylenediamine. The compounds such as 1 mM potassium cyanide, 10 mM sodium diethyldithiocarbamate, L-ascorbic acid, sodium hydrosulfite and L-cysteine inhibited completely while 1 mM of Ca^(2+) and Cu^(2+) activated the purified peroxidase.
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