Membrane Processing for Purification and Concentration of β-glycosidases from Barley (Hordeum vulgare)

Tangential flow ultrafiltration with a polyethersulfone
(100 kDa) membrane was used for the purification
and concentration of β-glycosidases (β-galactosidase and
β-glucosidase) from aqueous extract of barley. The performances
of mode 1 (concentration followed by diafiltration)
and mode 2 (diafiltration followed by concentration) were
compared. In mode 1 activity recoveries of 91.44 and 88%
as well as purifications of 1.84 and 1.77-fold for β-galactosidase
and β-glucosidase, respectively, were obtained in a
total processing time of about 9 h. In mode 2 activity recoveries
of 95.68 and 91.76% with purifications of 4.56
and 4.38-fold for β-galactosidase and β-glucosidase,
respectively, were obtained in a total processing time of
about 6 h. The removal of total carbohydrates and protein
was 56.74 and 50.73%, respectively, in mode 1, whereas it
was 81.46 and 79.04%, respectively, in mode 2. The
diafiltration volume and volume concentration of 3 were
maintained in both mode 1 and 2. Flux decline was severe
in mode 1 and led to a long processing time of about 9 h.
These results indicate that mode 2 was better than mode 1
for purification of β-glycosidases.