蛋白酶水解马铃薯淀粉对于淀粉化学性质改变的研究

本实验采用碱性蛋白酶酶解马铃薯淀粉和马铃薯直链淀粉,并用红外光谱、质谱、核磁共振氢谱和碳谱对酶解前后淀粉的化学结构进行表征。酶解改变了直、支链淀粉间相互影响的方式及淀粉中水的存在形式。酶解增加了马铃薯淀粉和直链淀粉的非晶相,马铃薯淀粉13C NMR中69.2、68.3、68.0、66.3、38.3ppm处的峰和1H NMR中4.7、3.6、3.3ppm处的峰与淀粉中蛋白相关。红外和质谱结果表明蛋白中Asp,Leu和Glu-C多肽可能与淀粉连接。 

Change of the chemical properties of the potato starch hydrolyzed by protease

In order to identify the chemical feature of potato starch which contains no protein, the potato starch and potato amylose were hydrolyzed by alkali protease and the change of their chemical structure were analyzed by IR, ESI- MS, 1H and13 C nuclear magnetic resonance spectroscopy. The results showed that hydrolysis of potato starch by protease changed the interaction pattern of potato amylose and amylopectin, which led to the loss of C- H stretching vibration of methelene.Interaction of amylose and protease altered the pattern of water in starch.Protease hydrolysis increased the amorphous phase of potato starch and amylose. Protease hydrolysis of potato starch caused the changes of potato starch in13 C NMR peaks at 69.2, 68.3, 68.0, 66.3, 38.3ppm and1 H NMR peaks around 4.7, 3.6, 3.3ppm. Analysis results of IR and ESI- MS suggested that the Asp, Leu and Glu- C peptides probably joined the connection of protein and potato starch.