α-乙酰乳酸脱羧酶的提取条件与应用研究

从ＢＤ－５菌株中提取α－乙酰乳酸脱羧酶，为提高酶的得率，探讨了破壁方法、除杂蛋白、硫酸铵沉淀提取粗酶等的条件，以及提取过程中酶的损失情况和菌体存放时间对酶活力的影响等。结果表明：该菌株的菌体用超声波破壁、５０％饱和度硫酸铵除杂蛋白，８０％饱和度硫酸铵提取粗酶效果较好，菌体存放时间过长，酶活力明显降低。将用该菌株提取的酶应用于啤酒发酵中，证明有明显的降低双乙酰的效果。

Extracting Conditions and Application Study of α-Acetolactatedecarboxylase

α-acetolactatedecarboxylase was extracted from BD-5 strain. In order to get more α-acetolactatedecarboxglase, the extracting process at different steps was examined such as breaking cell wall, removing contaminating proteins by (NH 4 ) 2 SO 4 sedimentation, the amount of enzyme lost during extracting, and the influence of storing time on α-acetolactatedecarboxylase activity. Through experiments, following conclusions was made: it had a better results when use supersonic waves to break cell wall, 50%～80% (NH 4 ) 2 SO 4 sedimentation to remove contaminating proteins and extract crude enzyme products. In addition, if the bacterium was stored top long, the α-acctolactatedecarboxylase activity would reduce. By using the α-acctolactate-decar-boxylase in prophase fermen tation of beer. It showed that the enzyme could obviously reduce the activity of beer yeast′s producing diacetyl.