壳聚糖/海藻酸钠固定木聚糖酶的研究

[目的]研究游离酶和固定化酶的酶学性质,并对壳聚糖固定木聚糖酶进行优化研究。[方法]以海藻酸钠和壳聚糖2种载体对木聚糖酶进行固定化,测定游离酶和固定化酶的活力。[结果]结果表明,壳聚糖吸附交联法、海藻酸钠包埋法固定木聚糖酶的固定率分别为51.8%、31.8%,Km值分别为0.524、0.748 g/L,游离酶的Km值为0.687 g/L。2种载体固定化木聚糖酶的酸碱稳定性均明显提高,最适反应温度和最适贮藏温度虽均与游离酶相同(最适反应温度是50℃,最适贮藏温度是30℃),但前者的适宜温度范围明显变宽;并且固定化酶提高了游离酶的贮藏稳定性。[结论]采用壳聚糖吸附交联法、海藻酸钠包埋法固定化木聚糖酶具有一定的工业应用价值。

Research on the Chitosan/Sodium Alginate Fixing Xylanase

[Objective] The property of free and immobilized enzyme was researched and the chitosan fixing xylanase was optimized.[Method] The vitality of free and immobilized enzyme was tested after the xylanase fixed by 2 carrier of sodium alginate and chitosan.[Result] The results showed that the fixed rate of xylanase in the method of cross-linking of chitosan adsorption and sodium alginate embedded was 51.8% and 31.8%;Km value was 0.524 g/L and 0.748 g/L,respectively;and the Km value of free enzyme was 0.687 g/L.The stability of acid/alkali of the xylanase fixed by 2 carrier of sodium alginate and chitosan obviously was improved and the optimum reaction and storage temperature were same as free enzyme(optimum reaction temperature was 50 ℃ and the optimum storage temperature was 30 ℃).However,the range of suitable temperature of the former was wider significantly than the later and the immobilized enzyme improved the storage stability of free enzyme.[Conclusion] The two fixed methods were with a value of industrial application.