双醛氧化纤维素固定胰蛋白酶性质研究

摘要

研究固定化酶载体-氧化型纤维素条件优化,并用此载体固定胰蛋白酶.结果表明,当氧化剂高碘酸钠浓度为0.5 mol·L-1,氧化环境pH 2,氧化时间为3.5 h,反应温度为35℃时,氧化纤维素醛基质量分数可到达74.06％.以此为载体固定胰蛋白酶,可得到固定化胰蛋白酶最适温度为60℃,最适pH 9.0,固定化酶比自由酶热稳定性提高.在最适条件下,固定酶可重复使用5次以上,之后活性才有所下降,将固定化酶置于4℃冷藏保存,5 d后活性保持在90％,固定化酶表现出较高使用和贮藏稳定性,为胰蛋白酶广泛应用奠定基础.%Sodium periodate were used to conduct the epoxidation and dialdehyde oxidation of cellulose for preparing epoxidized dialdehyde oxycellulose,The prepared epoxidized dialdehyde oxycellulose was used as the carrier to immobilize trypsin.The results showed that when the oxidant sodium periodate the concentration of 0.5 mol·L-1,at pH 2.0,after 3.5 h at 35 ℃,the oxidation was 74.06％.Immobilization conditions and the enzymatic properties of immobilized trypsin were investigated.The results showed that:the immobilized trypsin optimum temperature of 60 ℃ and the optimum pH value of 9.0.The immobilized enzyme to improve the thermal stability of the free enzyme.Under optimum conditions,the immobilized enzyme could be reused more than 5 times the activity began to decline,the immobilized enzyme showed a higher use and storage stability of the immobilized enzyme stored at 4 ℃ for 5 d after the activity maintained at 90％.