β-Galactosidase entrapment in silica gel matrices for a more effective treatment of lactose intolerance

Abstract

► A new pharmaceutical formulation for the treatment of lactose intolerance. ► A reliable and reproducible procedure for the immobilization of β-galactosidase. ► A one-pot entrapment of β-galactosidase in a silica network was optimized. ► The entrapment in a silica matrix can prolong the therapeutic action of lactase. ► The sol–gel technique preserves the stability of the enzyme. In this work we present a preliminary study directed to the realization of a new pharmaceutical formulation for the treatment of lactose intolerance. The main aim of the work is to increase the stability of β-galactosidase in order to prolong its activity in the course of time, thus improving its performance as dietary supplement in the digestion of lactose. We describe a reliable and effective procedure for the immobilization of β-galactosidase in a three-dimensional silica network. A one-step approach was optimized by using the sol–gel method to obtain homogeneous and stable β-galactosidase/silica gel composites; the textural properties of the porous surface were characterized by N 2 physisorption analyses. The activity of β-galactosidase was evaluated in vitro in the hydrolysis of o-nitrophenyl-β- d -galactopyranoside (used instead of lactose) at pH 7.4 and 37 °C, thus reproducing the conditions of the human intestine.