大麦制麦酶系中果胶酶的性质及形成机理

实验采用凝胶层析法从绿麦芽中分离、提纯出果胶酶 ,并对其性质、形成机理进行了研究。结果表明 :在麦汁中果胶酶最适pH值为 4 5 ,而纯果胶酶的最适 pH值为 4 0 ;低浓度的Na Cl、CaCl2 对果胶酶具有激活作用。果胶酶的形成机理与其他水解酶基本相同 ,其形成依赖于赤霉素 ,受胚所分泌的赤霉素刺激 ,同时 ,亦是多种因素 (如大麦麦芽中抑制蛋白、金属盐等 )共同作用的结果。

Characterization and Formation Mechanism of Pectinase in the Malt Enzyme System

In this experiment, pectinase was purified from malt by Gel chromatograhy. Its enzyme property and formation mechanism were studied. It is indicated that the optimal pH of crude pectinase in mash is about 4.5 while the pure pectinase in HAc NaAc solution is 4.0. The pectinase activity was activated by low concentration of sodium chloride and calcium chloride. Like the other hydrolysis enzyme, the formation of pectinase depends on an active gibberellin hormone in germination embryo which diffused to the aleurone cell to cause the formation and secretion of pectinase. Its formation was affected by several factors such as the barley, malt inhibitors and metal ions.