食品科学 ›› 2008, Vol. 29 ›› Issue (12): 431-434.

• 生物工程 • 上一篇    下一篇

蒜氨酸酶的分离纯化及其酶学性质测定

 曾哲灵, 徐仁华, 熊涛   

  1. 南昌大学食品科学与技术国家重点实验室;
  • 出版日期:2008-12-15 发布日期:2011-12-08

Purification of Alliinase and Determination of Its Enzymatic Properties

 ZENG  Zhe-Ling, XU  Ren-Hua, XIONG  Tao   

  1. State Key Laboratory of Food Science and Technology,Nanchang University,Nanchang 330047,China
  • Online:2008-12-15 Published:2011-12-08

摘要: 大蒜中功能成分含硫化合物是由蒜氨酸酶(alliinase,E C4.4.1.4)催化蒜氨酸(alliin)生成的。本实验通过提取、盐析、透析及层析,自新鲜大蒜中分离纯化出蒜氨酸酶,并测定了蒜氨酸酶的酶学性质。蒜氨酸酶的适宜分离纯化过程及条件为:pH7.0Na+/K+磷酸缓冲液提取,45%饱和度NH4(SO4)2盐析,10000×g离心沉淀30min,pH6.5的Na+/K+磷酸缓冲液溶解,截留1.4万分子量透析袋透析,Sephadex G-200层析,收集洗脱时间4.75h的洗脱液。蒜氨酸酶最适温度和pH值分别为30℃和6.3,Mg2+、Zn2+、Fe2+、Fe3+、EDTA-Na金属离子对蒜氨酸酶有激活作用,Fe3+激活作用最明显,Cu2+严重抑制蒜氨酸酶活性。以合成S-烯丙基-L-半胱氨酸亚砜为底物,蒜氨酸酶的Km为5.91mmol/L、Vmax为1.55μmol/min。

关键词: 蒜氨酸酶, 分离纯化, 酶学性质

Abstract: The aim of this study was to separate and purify alliinase from fresh garlic,and determine the enzymatic properties of alliinase. The optimal separation and purification process is as follows:to extract alliinase from fresh garli with Na+/K+ phosphate buffer(pH 7.0),salt out it with 45% saturated ammonium sulfate,separate it by centrifuge with 10000×g,dissolve precipitate in Na+/K+ phosphate buffer(pH 6.5) and dialyze using dialysis bag with 14000 molecular weight cutoff,purify alliinase with Sephadex G-200 column,and collect eluate when elution time is up to 4.75 h. The optimum temperature of alliinase is 30℃,and the optimum pH is 6.3. Mg2+,Zn2+,Fe2+,Fe3+,and EDTA-Na have active effects on alliinase,and the effect of Fe3+ is specially obvious,but alliinase would be seriously inhibited by Cu2+. The Km and Vmax values of alliinase are 5.91 mmol/L and 1.55μmol/min respectively when synthetical S-allyl-L-cysteine sulphoxide is used as basic substrate.

Key words: alliinase, purification, enzymatic properties