Purification and Properties of the Peroxidase in Castanea Semen

밤생율(生栗)에 함유된 Peroxidase의 정제 및 특성에 관한 연구

Peroxidase was purified to a homogeneous state from Castanea Semen by ammonium sulfate precipitation, DEAE-cellulose column chromatography, gel filtration on sephadex G-100 and HPLC, and the purification fold was 65.3. The molecular weight of the enzyme was estimated to be about 35,000 by HPLC. In properties of the enzyme which was purified up to sephadex G-100 column chromatography, the optimum pH and temperature were 5.0 and $50^{\circ}C$, respectively. By heating the enzyme at $80^{\circ}C$ for 1.73 min., the enzyme activity was decreased to 10%. The enzyme was active toward aromatic amines such as o-phenylenediamine and p-phenylendiamine. Kinetic studies indicated a Km of 2.6mM for o-phenylenediamine at an optimal hydrogen-peroxide concentration and a Km of 10mM for hydrogenperoxide at an optimal o-phenylenediamine concentration. Among the reagents tested, L-ascorbic acid and sodium L-ascorbate inhibited significantly the enzyme, while $Ca^{++}$ and $Ba^{++}$ activated the enzyme at the concentration of 1mM and 5mM.

밤(생율(生栗))으로 부터 peroxidase를 $(NH_4)_2SO_4$에 의한 염석 및 DEAE-cellulose column chromatography, sephadex G-100 column chromatography, HPLC방법으로 정제하였으며 정제도는 조효소에 비하여 65.3배였고, HPLC로 측정한 밤 peroxidase 분자량은 35,000으로 추정되었다. sephadexG-100 column chromatography 후 얻은 밤 peroxidase의 작용최적 pH는 5.0이었고, 작용최적 온도는 $50^{\circ}C$이었으며 $80^{\circ}C$에서 1.73분 열처리할 때 90%의 효소가 불활성화되었다. 본 효소는 OPDA 및 PPDA와 같은 방향족 amine류에 높은 활성을 나타내었다. OPDA와 $H_2O_2$에 대한 Km치는 각각 2.6mM과 10mM이었고, 저해작용은 L-ascorbic acid 와 sodium L-ascobate가 가장 컸으며, $Ca^{++}$과 $Ba^{++}$은 1mM과 5mM에서 현저히 효소활성을 증가시켰다.