Studies on Hemicellulases<subtitle>IV. Purification and Properties of the β-Xylosidase Produced by <italic>Aspergillus niger</italic> van TIEGHEM</subtitle>

Abstract

β-Xylosidase [EC 3.2.1.37] of Aspergillus nigeor van TIEGHEM was extracted from a culture on wheat-bran koji and purified by a series of the procedures including salting out with ammonium sulfate, DEAE-Sephadex column chromatography, gel-filtration on Sephadex G-150, and column electrophoresis. The purified β-xylosidase was practically free from xylanase [EC 3.2.1.8] and all other glycosidase activities tested. The purified enzyme was most active at pH values between 3 and 4 and stable over the range of pH's 4 to 7 at 30°C for 24 hr and below 70°C for 15 min. It showed a glycosyltransferase activity, and synthesized xylooligosaccharides from xylobiose and xylotriose.