α-淀粉酶及其复合酶体系对淀粉酶解性能研究

Study on the Starch Enzymolysis Performance of α-Amylase and Its Complex Enzyme System

中文关键词:  变性淀粉  α-淀粉酶  复合酶体系  酶解效率

Key Words:modified starch  α-amylase  complex enzymes  enzymatic hydrolysis efficiency

中文摘要:

      研究了单一α-淀粉酶体系及α-淀粉酶与β-淀粉酶、普鲁兰酶、糖化酶组成的二元、三元、四元复合酶体系，对3种造纸常用变性淀粉（氧化淀粉、酶解淀粉、阳离子淀粉）的酶解性能，探究不同α-淀粉酶用量对淀粉分解率和DE值的影响。结果表明，在单一α-淀粉酶体系中，淀粉分解率达到90%时，阳离子淀粉酶解所需α-淀粉酶用量约为其他2种淀粉的4倍；酶解淀粉加入柠檬酸抑制Zn²⁺后，其淀粉分解率最大可提高37.4%；二元复合酶体系中，α-淀粉酶/β-淀粉酶对阳离子淀粉的分解率比α-淀粉酶/糖化酶及α-淀粉酶/普鲁兰酶分别高5.3%和8.7%；三元复合酶体系中，α-淀粉酶/糖化酶/β-淀粉酶对阳离子淀粉的分解率比α-淀粉酶/糖化酶/普鲁兰酶高1.2%。在将α-淀粉酶/糖化酶/β-淀粉酶/普鲁兰酶的四元复合酶体系应用于阳离子淀粉、酶解淀粉、氧化淀粉的酶解反应时，达到淀粉分解率80%所需α-淀粉酶用量分别为单一α-淀粉酶体系的56%、38%和17%。

Abstract:

      This study investigated the enzymatic performance of single α-amylase and binary， ternary， and quaternary complex enzyme systems consisting of α-amylase with β-amylase， pullulanase and glucoamylase for three commonly used modified starches （oxidized starch， enzymatically hydrolyzed starch， and cationic starch）. The effect of different α-amylase dosages on starch enzymatic rate and DE value was explored. The results indicated that when the starch enzymatic rate reached 90% in single α-amylase system， the required amount of α-amylase for cationic starch enzymolysis was about 4 times than that of the other two kinds of starches. The enzymatic rate of enzymatically hydrolyzed starch could be increased by up to 37.4% when citric acid was added to inhibit zinc ions. In the binary complex enzyme system， the enzymatic rate of cationic starch by α-amylase/β-amylase was 5.3% and 8.7% higher than that by α-amylase/glucoamylase and α-amylase/pullulanase， respectively. In the ternary complex enzyme system， the enzymatic rate of cationic starch by α-amylase/glucoamylase/β-amylase was 1.2% higher than that by α-amylase/glucoamylase/pullulanase. In the application of α-amylase/glucoamylase/β-amylase/pullulanase tetrameric complex enzyme system to the enzymatic reactions of cationic starch， enzymatically hydrolyzed starch and oxidized starch， when the enzymatic rate of starch reached 80%， the required amount of α-amylase was 56%， 38% and 17% of that by single α-amylase system， respectively.