Reaction Product from D-Glucose by Crude Glucoamylase (<i>Aspergillus niger</i>)

WATANABE Toshiyuki, KAWAMURA Sugio, TANNO Mutsuko, MATSUDA Kazuo

doi:10.1271/nogeikagaku1924.42.5_304

Reaction product of glucoamylase (Aspergillus niger) was prepared by incubating 40% D-glucose solution with 0.68% of crude glucoamylase (Asp. niger mut. 19) at 55°C for 72_??_96hr, followed by inactivating the enzyme at 80°C for 10min. By paper chromatography and paper ionophoresis, kojibiose, nigerose, maltose, isomaltose, laminaribiose, gentiobiose, maltotriose, panose, isopanose and isomaltotriose were detected in the reaction product. The amount of reaction product of Aspergillus niger was 8.0% of the total sugar. This value was larger than that of Rhizopus niveus (3.2%) and Endomyces sp. (6.5%). Moreover, in the reaction product of Aspergillus niger, the content of isomaltose fraction was larger than that of maltose fraction.<br> Reaction product from 600g of D-glucose was fractionated by Carbon-Celite column using water and 2.5_??_15% ethanol as successive elution solvents. On acetylation of isomaltose fraction, isomaltose was identified as crystalline octaacetate. Kojibiose, nigerose and maltose were also isolated by successive Carbon-Celite and Magnesol-Celite column chromatography, and identified as their crystalline octaacetates. Panose was identified as crystalline panitol dodecaacetate. The enzyme used in this experiment showed transglucosylase activity in addition to the reverse action from D-glucose.<br> Therefore, there is some possibility that a part of the above reaction product was produced by the transglucosylation from maltose which had been first formed by reverse action.

Reaction Product from D-Glucose by Crude Glucoamylase (<i>Aspergillus niger</i>)

Bibliographic Information

Search this article

Description

Journal

Keywords

Details 詳細情報について

Export

Report a problem