Abstract
$\beta$-Galactosidase activity was not detected at green mature stage but were 21.79 and 380.23 units/100g-fr. wt. in mature and soft persimmon, respectively. The molecular weight of $\beta$-galactosidase was estimated to be 115, 000 daltons by the method of gel filtration. Vmax and Km value were 0.095m mo1e p-nitrophenyl-galactoside and 1.8$\times$10$^{-2}$ mM, respectively. The optimum temperature and pH of $\beta$-galactosidase were 45$^{\circ}C$ and 4.2, respectively. $\beta$-Galactosidase was inhibited by SDS.
$\beta$-Galactosidase는 미숙감에서는 활성이 없었으나, 완숙감과 연시에서 각각 21.79, 380.23 unit/ 100g-fr. wt.이었으며 연시에서 현저히 증가하였다. $\beta$-Galactosidase는 isoenzyme이 존재하지 않았고, 분자량은 115,000dalton이었다. $\beta$-Galactosidase의 Km값은 1.84$\times$$10^{-2}$ mM, Vmax는 0.095 mmole p-nitrophenyl-$\beta$-galactoside degraded/$m\ell$/ 15min.이었고 최적 pH는 4.2. 최적온도는 45$^{\circ}C$이었으며, 6$0^{\circ}C$에서 10분간 열처리하였을 때 활성이 50%소실되었다. $\beta$-Galactosidase의 활성에 SDS는 저해하였으나 Mg++과 Ca++은 영향을 주지 않았다.
