固定化菊粉酶连续降解菊芋果聚糖的研究

Continuous Hydrolysis of Fructans in Jerusalem Artichke Extracts by Using an Immobilized Inulinase

克鲁维酵母（Ｋｌｕｙｖｅｒｏｍｙｃｅｓｓｐ．）Ｙ－８５产生并经部分纯化的胞内菊粉酶（ｅｎｄｏｃｅｌｕｌａｒｉｎｕｌｉｎａｓｅ），采用共价键交联吸附法固定化．以菊芋果聚糖为底物测定，所制得固定化酶在ｐＨ５．０和温度５５℃下反应显示最大活性，对热的稳定性和贮存稳定性比游离酶明显提高，并显示出外切菊粉酶（ｅｘｏｉｎｕｌｉｎａｓｅ）性质．在装有１７．６ｍＬ固定化酶填充床反应器（ｐａｃｋｅｄ－ｂｅｄｒｅａｃｔｏｒ）中，以１．７ｈ－１的空间速度进料，５０℃下连续操作４ｄ，４．５％菊芋果聚糖液可被１００％降解，反应器定容产率为７７．０ｇ·Ｌ－１·ｈ－１，半衰期２７ｄ。

The partially purified endocllular inulinase from Kluyveromyces sp. Y 85 was immobilized by adsorb crosslinking method.The maximum inulinase activity occurred at pH5.0 and 55℃.Thermal and storage stability of the enzyme were improved by immobilization. It is an exoinulinase. In an packed bed column reactor containing 17.6 mL of the immobilized inulinase,a 4.5%(W/V)solution of fructans in J.A extracts was completely hydrolyzed at a space velocity of 1. 7 h -1 at 50 ℃ over a 4d period of continnuous operation.The volumetric productivety in the reactor was 77 g·1 -1 ·h -1 ,a half life of the immobilized inulinase was 27 days. The reaction products were fructose (85%) and glucose (15%).