Abstract
By paper chromatography, two new spots having reducing power on 2,6-dichlorophenol-indophenol and silver nitrate beside the spot of L-ascorbic acid were found in the incubation mixture containing partially purified transglucosidase from Aspergillus niger IAM 2534,maltose, sodium L-ascorbate and thiourea. The new derivatives were also precipitated as lead compounds in diluted alkali solution like as L-ascorbic acid. The lead precipitate was purified by washing with diluted alkali solution, and by repeated process of liberation from lead precipitate at pH 3.0 by sulfuric acid and reprecipitation as lead compounds in diluted alkali solution until no more free sugar was detected on paper chromatogram. Hydrolysis of the purified derivatives in N H_2SO_4 or with the partially purified transglucosidase from Asp. niger gave D-glucose and L-ascorbic acid. D-Glucose was identified by glucose oxidase and by paper chromatography. From these results, two new derivatives enzymatically formed from AsA and maltose are thought to be L-ascorbic acid glucoside-like and its oligosaccharide-like compounds.
