金属离子对4PCA饲料酶中木聚糖酶活性的影响

目的]为酶制剂的稳定性研究及其在饲料工业中的应用提供依据。方法]选取K+、Na+、Ca2+、Mg2+、Zn2+、Mn2+、Cu2+和Fe2+8种金属离子,浓度设计为1×10-4、1×10-3、1×10-2mol/L,研究金属离子对4PCA饲料复合酶中木聚糖酶活性的影响。结果]浓度为1×10-4mol/L时,8种金属离子对木聚糖酶活性无明显影响。浓度为1×10-3mol/L时,Cu2+使木聚糖酶活增至125.8%,Mn2+使木聚糖酶活降至54.5%。浓度为1×10-2mol/L时,Zn2+使木聚糖酶活增至121.5%,Mn2+、Cu2+、Fe2+分别使木聚糖酶活降至40.6%、67.7%、88.9%。结论]K+、Na+、Ca2+、Mg2+对木聚糖酶活性无特别影响,Zn2+有激活作用,Mn2+、Fe2+有抑制作用,Cu2+随着浓度的增加有先激活后抑制作用,3种离子的抑制作用由大到小依次为:Mn2+>Cu2+>Fe2+。

Effects of Metal Ions on Activity of Xylanase in Complex Enzyme of 4PCA Feedstuff

Objective] The study was to provide the basis for stability study on enzyme preparation and its application in feed industry.Method] 8 kinds of metal ions including K+,Na+,Ca2+,Mg2+,Zn2+,Mn2+,Cu2+ and Fe2+ were selected and they were designed to different concn.of 1×10-4,1×10-3 and 1×10-2 mol/L.The effects of metal ions on activity of xylanase in complex enzyme of 4PCA feedstuff were studied.Result] When the metal ions was 1×10-4 mol/L,8 kinds of metal ions all had no obvious effect on activity of xylanase.When the metal ions was 1×10-3 mol/L,Cu2+ could increase the activity of xylanase to 125.8%,but Mn2+ could decrease the activity of xylanase to 54.5%.When the metal ions was 1×10-2 mol/L,Zn2+ could increase the activity of xylanase to 121.5%,but Mn2+,Cu2+ and Fe2+ could decrease the activity of xylanase to 40.6%,67.7% and 88.9% resp.Conclusion] K+,Na+,Ca2+ and Mg2+ had no especial effect on activity of xylanase,Zn2+ had activation effect on it and Mn2+ and Fe2+ had inhibition on it.With the increasing of Cu2+ concn.the effect of Cu2+ on activity of xylanase was firstly activation and then inhibition,and the inhibition of 3 ions on activity of xylanase in order was Mn2+>Cu2+>Fe2+.