Thermomyces lanuginosus CBS 395.62/b Strain as Rich Source of
α-Galactosidase Enzyme

Abstract

Seventeen Thermomyces lanuginosus strains, cultivated on raffinose and sucrose, were ranked on the basis of
α-galactosidase activities. T. lanuginosus CBS 395.62/b strain showed the highest
α-galactosidase activity on both investigated carbohydrates. Several carbon sources were tested as potential inducers for the
α-galactosidase synthesis. On melibiose substrate
α-galactosidase activity was higher in the intracellular fraction than in the filtrate of the fermentation broth, although both values were very low and did not reach the value of 1 U/mL. Raffinose, sucrose and Lactosucrose® proved to be inducers for
α-galactosidase production. The highest titer (about 30 U/mL) was achieved on 1 % sucrose and 0.45 % ammonium acetate. The optimum sucrose and ammonium acetate concentrations, at which about 90 U/mL
α-galactosidase activity was reached during an 8-day fermentation, were 3 and 0.9 %, respectively.

Keywords

• α
  -galactosidase
• fermentation
• enzyme production
• Thermomyces lanuginosus