响应面法优化固定化荧光假单胞菌磷脂酶B的研究

以脱胶油磷含量为响应值,采用响应面法和Central-Composite设计对制备固定化荧光假单胞菌磷脂酶B(PfPLB)主要工艺参数(海藻酸钠浓度、壳聚糖浓度和加酶量)进行了优化,并且采用回归分析拟合了三个固定化因子与响应值(磷含量)的回归模型.该模型预测最佳的固定化Pf-PLB条件为:海藻酸钠3%,壳聚糖1.14%,加酶量1000 U/kg.研究固定化Pf-PLB的酶学性质,结果表明其最适反应温度为40℃,比游离酶提高15℃;最适反应pH为5.5,比游离酶降低1个pH单位.固定化Pf-PLB具有较好的酶活稳定性,连续反应6次,其相对活性为初始值的51.6%,显示出良好的应用前景.

Study on Optimization of Preparing Immobilized Phospholipase B by Response Surface Modeling

Response surface modeling combined with central composite design was employed for the optimization of the final immobilized Pf - PLB condition, such as Sodium alginate concentration, chitosan concentration and Pf -PLB dosage. The residual phosphorus content of degummed oil was chosen as the response value. And the mathematical regression model between different variables and the residual phosphorus content was obtained using regression analysis. The optimal immobilization condition was： Sodium alginate 3.0%, chitosan 1.14%, Pf - PLB dosage of 1000 U/kg. The immobilized Pf - PLB exhibited the maximal activity at 40℃ and pH 5.5. The immobilized enzyme could retain 51.6% residual activity after 6 consecutive operations, which showed a good application potential in the degumming of vegetable oils.