实验用CaCl2溶液从脱脂米糠中提取解脂酶，经(NH4)2SO4沉淀后，获得粗酶。用分光光度法测定了六种不同的金属离子对酶活力的影响，实验结果表明，在浓度为0.01 mol/L时，Zn2+、Fe2+、Mg2+等金属离子对米糠解脂酶起激活作用，Ca2+、Ba2+、Cu2+等离子对酶活性起抑制作用。当离子浓度在0.001 mol/L到0.1 mol/L之间变化时，随着离子浓度的增加，Ca2+、Ba2+、Cu2+三种金属离子会使酶的活性逐渐降低；而Zn2+、Fe2+、Mg2+三种金属离子浓度在0.001~0.02 mol/L的变化范围内，酶活性随着离子浓度的升高而逐渐升高，在0.02~0.1 mol/L的变化范围内，酶活性随着离子浓度的升高而逐渐降低。

Crude lipase was extracted from defatted rice bran with calaium chloride and subsequently precipitated with CaCl2 solution. Effects of six kinds of metal ions on the lipase activity were investigated. Results showed that when several metal ions, including Zn2+、Fe2+ and Mg2+ with suitable concentration being of 0.01 mol/L, could enhance the lipase activity, while Ca2+、Ba2+ and Cu2+ inhibited its activity. When the concentration of metal ions (Ca2+、Ba2+ and Cu2+) ranged from 0.001mol/L to 0.1 mol/L, its activity decreased with the increase of concentration of those metal ions, but was improved by increasing the concentration of other metal ions (Zn2+, Fe2+ and Mg2+) from 0.001mol/L to 0.02 mol/L. However, further raising the concentration of Zn2+, Fe2+ and Mg2+ from 0.02 mol/L to 0.1 mol/L. will lower its activity.