木瓜蛋白酶对丝素的作用

The effect of papain treatment on fibroin

首先用Na2CO3反复脱胶将蚕丝丝胶全部去除,再用木瓜蛋白酶直接对脱胶后的丝素进行处理,以此研究木瓜蛋白酶对丝素的作用。进一步测试木瓜蛋白酶处理前后蚕丝断裂强度,并进行扫描电镜观察和X射线衍射表征。实验结果表明,木瓜蛋白酶对丝素的水解率很小,处理后丝素断裂强力下降,表面微观形貌有较大的损伤,酶处理不会改变丝素晶型,但破坏了丝素结晶结构,使结晶度下降。丝素强力损失随处理时间延长、酶浓度增加而增大,随温度升高先增大后减小。

In this paper,silk sericin was degummed repeatedly with Na2CO3. Then,papain was used to treat degummed fibroin so as to study the effect of papain on fibroin. The breaking strength before and after papain treatment was further tested. Meanwhile, SEM observation and X ray diffraction characterization were conducted. The experimental result shows that the hydrolysis rate of fibroin is small,but the breaking strength of fibroin declines and the microscopic surface damages greatly. Papain treatment will not change crystal form of fibroin,but destroys crystalline structure of fibroin. Besides,the degree of crystallinity declines. The strength loss of fibroin rises as treatment time extends and enzyme concentration increases,but it first increases and then decreases with the rise in the temperature.