Abstract:

An intracellular β-glucosidase from Vintage Red Yeast was purified by ion exchange column chromatography.
The effects of temperature, pH, metal ions, glucose and alcohol on the stability of the purified β-glucosidase were studied.
The results showed that the enzyme was purified to 19.41 folds with a yield of 38.67%. The purity of β-glucosidase was
determined by sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE). One band was obtained with a
molecular mass of about 45 kD. Characterization of the purified β-glucosidase indicated good thermostability in the range
from 20 to 40℃ and good pH stability in the range from 5.0 to 10.0. The enzyme activity was strongly inhibited by Al3+, and
Cu2+, whereas K+, Mg2+, Ca2+, Zn2+ and Na+ had no effect on the β-glucosidase activity. Glucose and alcohol did not have
significant inhibitory effect on the β-glucosidase activity.

Key words: vintage red yeast, β-glucosidase, purification, enzymatic characterization