胰酶水解干酪素的动力学行为

Kinetic Behavior of Pancreatic Digestion of Casein

研究了胰酶水解干酪素制备蛋白胨过程中胰酶在不同温度下的失活行为 ,以及底物浓度对反应速率和平衡的影响 ,p H对反应浓度和平衡的影响。胰酶在 4 0°C下 4 h基本不丧失水解大分子的活力 ;在 50°C,1 30 min、55°C,1 1 0 min、6 0°C,90 min完全丧失对大分子的水解活性。胰酶短时间在高温下丧失的活性 ,当其返回到 4 0°C时可部分恢复。底物和产物对反应有抑制作用。底物初始浓度高 ,最终平衡转化率低。当 p H 8时的反应速率最快。

The kinetic behavior of pancreatic digestion of casein was studied at different temperatures, substrate concentration and pH values. Pancreatin would usually retain the activity of digestion of large molecules for at least 4 hours at 40°C, however it would completely lost the activity of digestion of large molecules in 130 minutes at 50°C, 110 minutes at 55°C, and 90 minutes under 60°C. Within a short period of time the lost activity caused by exposing to high temperatures (under 60°C) would be recovered partially. Both substrate and product can inhibit the reaction. Substrate has high initial concentration but low final equilibrium conversion. At pH8 is has the highest reaction rate.