배추흰나비(Pieris rapae L.)의 탈피에 관여하는 chitinolytic enzymes에 대한 기초자료로서, 변태시기에 따른 효소의 활성, 최적 pH, 온도의 영향, 그리고 열안정성 등을 조사하였다. 두 효소 모두 5령 유충말기에서 최대 활성을 나타내었으며, pH 7.0에서 최적을 나타내었다. 또한 최적 반응온도는 chitinase가 4$0^{circ}C$, chitobiase는 6$0^{circ}C$ 부근이었으며, 6$0^{circ}C$에서 chitinase가 40분까지 비교적 안정성을 보였으나 그 이후 약 40%가 활성을 잃었고, chitobiase는 60분에서 약 20%가 활성을 잃었다.
The activity of enzyme, the effect of pH and temperature on reaction, and the heat stability were investigated as a part of basic information for the chitinolytic enzymes involved in molting in integument of Pieris rapae. The activities of two enzymes with stages show the highest value at the late 5th instar stage. Optimal pH of chitinase is around 7. 0 and chitobiase also has optimal pH of 7.0 but shows high activity over the relatively broad range (pH of 5.0∼7.0). Reaction temperature shows highest activity at 40$^{circ}C$ for chitinase but at 60$^{circ}C$ for chitobiase. Chitinase maintains relative stability up to 40min. at 60$^{circ}C$ and then lost about 40％ of activity whereas chitobiase keeps stability up to 20min. but lost 20% of activity after 60 min.
