【摘要】 使用硅藻土载体和乙二醇缩水甘油醚进行吸附-交联固定海洋脂肪酶。采用单因素与正交实验结合的实验方案,确定最佳吸附条件为20℃,pH 5.0的0.1 mol/L柠檬酸钠缓冲液,载体投放量为2 g,吸附固定化时间为6 h。交联最佳温度条件为30℃,交联时间为6 h,乙二醇缩水甘油醚浓度为1.2%。吸附交联后酶活达124.83 U/g,酶活回收率高达67.31%。固定化脂肪酶连续操作5次依然保持良好的酶活性,对比游离酶,最适反应pH没有变化,但是最适反应温度固定化酶为50℃,提升5℃。同时,固定化脂肪酶显示出较好的机械稳定性和储存稳定性。结果证明硅藻土吸附-交联固定化海洋脂肪酶在工业酶固定化上有良好的应用前景。更多还原

【Abstract】 This study carried out the immobilization of marine lipase through adsorption/cross?linking method using kieselguhr and ethylene glycol glycidyl ether.Through single?factor and orthogonal experiments,the optimal adsorption conditions were determined as follows:0.1 mol/L sodium citrate at 20 ℃,pH 5.0,2 g car?rier dosage,adsorption time being 6 h;the optimal cross?linking conditions were determined as follows:30 ℃,cross?linking time being 6 h,and the concentration of ethylene glycol glycidyl ether being 1.2 %.The activity of prepared immobilized lipase reached 124.83 U/g,and the recovery rate of lipase activity was as high as 67.31 %.The immobilized lipase still maintained good enzyme activity after continuous operation for 5 times.Compared with free lipase,the optimal reaction pH of immobilized lipase was the same,but the optimal reaction tempera?ture for the immobilized lipase was 50 ℃,5 ℃ higher than that for free lipase.At the same time,the immobilized lipase showed better mechanical stability and better storage stability.These results show that the immobilization of lipase by adsorption-crosslinking method using kieselguhr as the absorbant possesses good application pros?pect in industry.更多还原