Efficient and rapid purification of lentil -galactosidase by affinity precipitation with alginate.

-Galactosidase (-D-galactoside galactohydrolase, EC 3.2.1.22) was purified (26-fold) from the germinating seeds of lentil (Lens culinaris) by affinity precipitation with alginate. The purified enzyme gave a single band corresponding to molecular mass of 40 kDa on SDS-PAGE. The optimum temperature and pH of the enzyme were determined as 40oC and 5.5, respectively. The enzyme was very stable at a temperature range of 4-65oC and at a pH range of 4-7. The values of kinetic constants Km and Vmax using p-nitrophenyl--D-galactopyranoside (PNPG) as substrate were 0.191 mM and 0.73 U, respectively. Results suggest that affinity precipitation is an attractive process for the purification of -galactosidase.