Aspergillus pulverulentus YM-80の産生するβ-グルコシダーゼの精製と諸性質およびその応用

摘要: A fungus, strain YM-80, isolated from a soil sample produced β-glucosidase ( β-D-glucoside glucohydrolase EC 3.2.1.21) in solid culture. The fungus was identified as Aspergillus pulverulentus its taxonomical characteristics. purified 18-fold the culture extract by (NH4)2SO4 precipitation, DEAE-Toyopearl 650M, Butyl-Toyopearl 650M and Sephacryl S-200 chromatography. enzyme appeared single band on SDS-PAGE. molecular weight of estimated to be 118,000 SDS-PAGE 240,000 gel filtration. an acidic protein with pI 4.5 specific activity 308 U/mg protein. optimum temperature pH for were 60°C 4.0, respectively. This stable range 3.0-7.0 also up 50°C. completely inhibited Hg2+ SDS. active broad β-linked glucosides but not α-linked saccharides. Added during tofu processing, useful preparation aglycon isoflavone-enriched hydrolysis glucoside form. However, isoflavones 6"-O-acetyl 6"-O-malonyl converted into