鱿鱼内脏蛋白酶的提取工艺研究

Extraction of Protease from Squid Viscera

摘要:

本文以鱿鱼内脏为原料提取蛋白酶。考察了各因素对提取效果的影响，包括用于提取的NaCl溶液浓度、内脏和提取液的固液比、提取温度、提取时间等。此外，根据蛋白质等电点沉淀原理，调粗酶液的pH值去除杂蛋白；并进一步比较了各种絮凝剂去除粗酶提取液中杂蛋白的效果。结果表明：NaCl溶液浓度为0.5%，固液比为1.0:1.5，常温下提取60 min可达到较好的提取效果，蛋白酶的回收率达到96.06%，比酶活达到1.33 U/mg。调粗酶液的pH值为4.5左右，杂蛋白去除效果较好；Fe2(SO4)3是较好的絮凝剂，向粗酶液中添加1% Fe2(SO4)3溶液，当添加比为4:1（V/V，粗酶液/Fe2(SO4)3溶液）时，进一步去除杂蛋白的效果较好，蛋白酶的回收率达80.33%，比酶活达到9.37 U/mg。

Abstract:

In this paper, extraction of protease from squid viscera was studied. Factors such as the concentration of NaCl solution used in protease extraction, the ratio of squid viscera solid to NaCl solution, extracting temperature, extracting time and so on, which influenced the extraction effect, were investigated. The pH of the crude protease extraction solution was adjusted to remove impurity based upon the isoelectric precipitation principle. Various flocculants were compared in terms of their removing effect of impurity from crude protease extraction solution. Results showed that the optimal extracting conditions were as follows: the concentration of NaCl solution 0.5%, the ratio of solid to solution 1.0:1.5, ambient temperature and extraction time 60 min. Under the above-mentioned conditions, 96.06 % of total protease activity was recovered; the specific protease activity reached 1.33 U/mg. by Adjusting the pH of crude protease extraction solution to 4.5, the impurities was removed. Among various flocculants, Fe2(SO4)3 was found to be the best. By adding 1% Fe2(SO4)3 solution to crude protease extraction solution, the impurities can be removed when the ratio of crude protease extraction solution to Fe2(SO4)3 solution reaching 4:1 (V/V). Under such conditions, 80.33 % of total protease activity was recovered; the specific protease activity reached 9.37 U/mg.