The hydrolysis reaction of amylases under supercritical carbon dioxide

• Main Authors: Chen, Ya-Lei, 陳亞雷
• Other Authors: Liu, Hwai-Shen
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/30520745601613359947

碩士 === 國立臺灣大學 === 化學工程學系 === 86 === This study mainly investigated the hydrolysis reaction of amy- lases (β-amylase or isoamylase) under the supercritical carbon dioxide. The results were compared with those under atmospheric pressure. Moreover, multiple enzymes of β- amylase and isoamylase was also evaluated. We found that the optimal conditions to be 50℃, and pH is 4.5 under atmospheric pressure. Experimental results indicated that the optimal pH value for β-amylase reaction under atmospheric pressure was 5.2, compared with the value of 5.7 in the supercritical carbon dioxide system. For multiple enzymes system, the optimal pH was 4.5 under atmospheric pressure but became 5.0 in the supercritical carbon dioxide system. With soluble starch as reaction substrate, the optimal agitation was 250 rpm under atmospheric pressure but 150 rpm in the supercritical carbon dioxide. On the other hand, the optimal agitation was 750 rpm under atmospheric pressure but 500 rpm in the supercritical carbon dioxide system when amylopectin or starch was as substrate. The comparison of reaction rate of β-amylase and isoamylase between under supercritical carbon dioxide system and in atmospheric pressure system was also evaluated . The results showed that in low viscosity substrate such as soluble starch, the reaction rate in the supercritical carbon dioxide system was quite similar with in the at- mospheric pressure system. When hydrolyzing high viscosity sub- strate such as amylopectin and starch, the reaction rate became superior in supercritical carbon dioxide system.