Purification and Characterization of β-Fructofuranosidase from Aspergillus japonicus TIT-KJ1

Abstract

Aβ-fructofuranosidase (EC 3.2.1.26) was purified to homogeneity from Aspergillus japonicus TIT-KJ1. The enyme had an optimum pH for activity of 5.4 and pH stability at 7.0-8.4. The optimum temperature at pH 5.4 was 60°C. The enzyme had a molecular weight of 236, 000 with two subunits and an isoelectric point of pH 4.0. The enzyme was inactivated by 5 mM Hg²⁺ and Ag⁺. The enzyme had a high transfructosylating activity. Treatment of 50% (w/v) sucrose with the enzyme under optimum conditions afforded more than 55% fructooligosaccharides.