The enzyme, alpha-galactosidase was extracted from peanuts using various buffers
and solvents. The specific activity of soluble preparation of peanut ranged from
0.0083 to 0.0606 U/mg. Phosphate buffer extract showed the maximum specific
activity of 0.0606 U/mg. The soluble alpha-galactosidase was immobilised in calcium
alginate beads and the specific activity of the immobilized enzyme was found to
be 0.0808 U/mg. Activity yield was 33%. The immobilised enzyme showed
increase in activity compared with the soluble enzyme above 35 C. The thermal
stability of the immobilised alpha-galactosidase was significantly improved in
comparison to the soluble form. The effect of different pH depicts that at acidic
pH the activity of the immobilised alpha-galactosidase was higher than that of the
soluble enzyme. The Km and Vmax for immobilised enzyme was higher when
compared with the soluble enzyme. Immobilised alpha-galactosidase retained 20%
activity after 7 repeated uses. The immobilised enzyme exhibited high storage
stability. The immobilised enzyme was used in batch and continuous packed bed
reactors for the hydrolysis of stachyose and raffinose in soymilk. Flatulence
causing raffinose and stachyose, after hydrolysis, was removed to a remarkable
extent. Hydrolysis of flatulence causing oligosaccharides of soymilk in a
continuous packed bed reactor has not been attempted previously.
