Galactose competitive inhibition of β-galactosidase (Aspergillus oryzae) immobilized on chitosan and nylon supports

Abstract Contrasting results have been published about the nature of galactose inhibition of β-galactosidase. In view of lactose hydrolysis in milk, we studied the inhibition of β-galactosidase (Aspergillus oryzae) immobilized on chitosan beads or a nylon membrane (Immunodyne). In both cases, competitive inhibition has been found. The Ki value for the β-galactosidase/chitosan system was higher than the one for the β-galactosidase/Immunodyne, showing that the former system is more appropriate to perform lactose hydrolysis. A new technology based on the use of nonisothermal bioreactors is suggested to overcome the inhibition problems.

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