以明胶为载体,戊二醛为交联剂,采用包埋-交联法制备固定化木聚糖酶,探讨明胶浓度、戊二醛体积分数、交联时间和固定化时间对固定化酶相对酶活力的影响.通过正交实验确定木聚糖酶的最佳固定化条件,比较固定化酶与其游离酶的最适反应温度、热稳定性、最适反应pH及pH稳定性.研究发现,在明胶浓度为15％、戊二醛体积分数为4％、交联时间为lh和固定化时间为3h时,固定化酶的回收率可达72.56％,同时固定化和游离酶的最适温度分别为50、60℃,最适pH分别为3.6、4.6,pH稳定性及热稳定性有显著提高.%Xylanase was immobilized with gelatin and cross linked with glutaraldehyde. The effect of reaction conditions (the concentration of gelatin, glutaraldehyde concentration, cross-linking time and immobilized time) on the relative activity of immobilized xylanase were tested. The most optimal immobilized conditions were determined with orthogonal test. At the same time the most suitable immobilized temperature, thermal stability, the most appropriate reacted pH and the pH stability of the immobilized xylanase were compared with that of the free enzyme. The result showed that the best immobilized condition was obtained. The recovery rate of immobilized xylanase was 72.56% when the concentration of gelatin was 15% ,the volume fraction of glutaraldehyde was 4%,the cross-linked time was 1h and the immobilized time was 3h. Simultaneously the most suitable immobilized temperature was respectively 50℃ and 60℃,the most appropriate pH was respectively 3.6 and 4.6 of the immobilized xylanase and the free enzyme. The pH stability and the thermal stability were obviously improved.
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