水合氧化钛固定化胰蛋白酶的特性

CHARACTERISTICS AND PROPERTIES OF IMMOBILIZED TRYPSIN BY HYDROUS TITANIUM OXIDES

用简便的水合氧化钛螫合法固定化胰蛋白酶,其残活力可达99.2%,载体可以回收。固定化酶的最适pH为10.3比自然酶高两个pH单位。它的最适温度为55℃比自然酶高0.5℃,自然酶在90℃已完全失去活力,而固定化酶在100℃仍具有20%的活力。稳定性试验显示,自然酶在13小时内活力直线下降到零,而固定化酶在5小时之内活力下降55%,5小时以后下降缓慢,250小时仍具20%活力。

Crude trypsin was immobilized by simply using the hydrous titanium oxides. After immobilization, 99.2% of enzyme activity was Kept. The optimum pH of the immobilized enzyme was 10.3, which was two units higher than that of natural enzyme, The optimum temperature of immobilized enzyme was 55C, which was 0.5 degree higher than that of natural enzyme, Moreover, as the temperature rose to 90℃, the activity of natural enzyme was completely lost. However, the immobilized enzyme still kept 20% activity when the temperature reached100℃. In the condition of 40℃, the stability test showed that the activity of natural enzyme was steeply dropped down to the zero in 13 hours. Whereas, the activity of immobilized enzyme was decreased to 55% after 5 hours then decreased slowly; and it still kept 2(?)% of enzyme activity after 250 hours.