木瓜蛋白酶降解甲壳胺的研究

采用一种木瓜蛋白酶过甲壳胺进行降解。研究了酶用量、pH值、温度、时间四个因素对反应的影响。其中,温度的影响作用显著,时间具有较小的影响作用(pH:3.0～6.0;温度:30°～60℃;时间:2～8h)。实验结果表明降解反应不遵循简单的动力模式。在pH4.0、40°C、8h、1.5mg/mL木瓜蛋白酶的条件下,分子量为(5～10)×105时用甲壳胺可容易地被木瓜蛋白酶降解为高度解聚的甲壳胺。

A Research on the Depolymerization of Chitosan with the Aid of Papain

One kind of papain was used to depolymerize chitosan in this paper. Four factors of reactions were studied including concentration of enzyme, pH, temperature and time. The result indicated that temperature influenced the depolymerization of chitosan efficiently, while time had relatively little effect on it with pH from 3.0 to 6.0, temperature from 30℃ to 60℃, and time from 2 to 8 hours. The data revealed that the enzymatic process did not obey a simple kinetic model; chitosan with average molecular weights in the range (5-10)×105 could be easily depolymerized to highly polydisperse chitosans under conditions such as pH 4.0, 40℃, 8 hrs, and papain 1.5 mg/mL.