Calcium alginate entrapped preparation of α-galactosidase: its stability and application in hydrolysis of soymilk galactooligosaccharides

Abstract

Thermostable α-galactosidase from Aspergillus terreus (GR) was insolubilized using concanavalin A obtained from jack bean extract and in order to maintain the integrity of complex in the presence of its substrate or products, this complex was crosslinked with glutaraldehyde. Soluble α-galactosidase entrapped in calcium alginate retained 82% of enzyme activity whereas, Con A-α-galactosidase complex entrapped in calcium alginate and crosslinked Con A-α-galactosidase complex entrapped calcium alginate retained 74 and 61% activity, respectively. A fluidized bed reactor was constructed for continuous hydrolysis of galactooligosaccharides in soymilk using crosslinked Con A-α-galactosidase complex entrapped calcium alginate. Optimum conditions such as pH (5.0) and temperature (65°C) were the same for all immobilized enzyme preparations and soluble enzyme. Crosslinked Con A-α-galactosidase entrapped complex exhibited enhanced thermostability and showed 62% of activity (38%) after 360 min at 65°C. Entrapped crosslinked Con A-α-galactosidase complex preparation was superior in the continuous hydrolysis of oligosaccharides in soymilk by batch processes compared to the other entrapped preparations. The entrapped crosslinked concanavalin A-α-galactosidase complex retained 95% activity after eight cycles of use.

Dried alginate-entrapped enzymes (DALGEEs) and their application to the production of fructooligosaccharides

“…The diffusion out of the beads can be minimised by increasing alginate concentration and/or mannuronic (M)/guluronic (G) acid ratio, as well as decreasing the pH [8]. Among other strategies to avoid protein leakage, enzymes can be cross-linked with glutaraldehyde [9] or bound to a carrier such as activated coal [10] prior to the entrapment process. In another recent twist, the crosslinking of alginate with glutaraldehyde has been also explored [11;12].…”

Continuous Packed Bed Reactor with Immobilized β-Galactosidase for Production of Galactooligosaccharides (GOS)

“…Covalent immobilization has the advantage of forming robust linkages between the enzyme and the carrier, which minimizes the loss of activity caused by enzyme leakage from the support [10], extends its lifetime by protecting the three-dimensional structure of the protein [11] and allows the development of continuous processes. The use of immobilized β-galactosidases in continuous bioreactors has mostly been applied to the hydrolysis of lactose in cheese whey [12][13][14]. In contrast, the production of GOS in continuous bioreactors has been scarcely studied [15][16][17].…”

Present status on removal of raffinose family oligosaccharides - a Review

“…emersonii, Ther. lanuginosus, Rhizomucor miehei, etc., display stability with a broad pH range and their highest activity is usually above 60°C (Shibuya et al 1997;Gote et al 2006;Simila et al 2010;Shankar et al 2011;Katrolia et al 2012;Wang et al 2015Wang et al , 2016. Other α-galactosidases, such as A. niger, A. oryzoe, Cl.…”