Affinity Covalent Immobilization of Glucoamylase onto ρ-Benzoquinone Activated Alginate Beads: I. Beads Preparation and Characterization

Abstract

ρ-Benzoquinone-activated alginate beads were presented as a new carrier for affinity covalent immobilization of glucoamylase enzyme. Evidences of alginate modification were extracted from FT-IR and thermal gravimetric analysis and supported by morphological changes recognized through SEM examination. Factors affecting the modification process such as ρ-benzoquinone (PBQ) concentration, reaction time, reaction temperature, reaction pH and finally alginate concentration, have been studied. Its influence on the amount of coupled PBQ was consequently correlated to the changes of the catalytic activity and the retained activity of immobilized enzyme, the main parameters judging the success of the immobilization process. The immobilized glucoamylase was found kept almost 80% of its native activity giving proof of non-significant substrate, starch, diffusion limitation. The proposed affinity covalent immobilizing technique would rank among the potential strategies for efficient immobilization of glucoamylase enzyme.

Immobilization of Enzymes in/on Membranes and their Applications

“…Pretreatment of the membranes with functionalizing reagents is commonly applied for covalent immobilization, including the wet chemical method, the UV‐induced method, the γ‐irradiation method and the plasma method . By doing so, the surface or the pores of the membrane are coated with active groups such as amino, hydroxy, carboxy, azido, amido, etc., which are then covalently linked to the chemical groups, including carboxy, amino, hydroxy, sulfhydryl or tyrosine groups, of the enzymes . The membrane modification is critical for covalent immobilization.…”

Covalent immobilization of β‐galactosidase onto amino‐functionalized PVC microspheres

“…Immobilization of β‐galactosidase can be achieved by various methods such as adsorption, covalent attachment, chemical aggregation, entrapment, and micro‐encapsulation 17, 22, 24–27. Among the various methods available for enzyme immobilization, covalent binding is particularly important because it leads to preparation of stable enzyme derivatives 28–37.…”

Production and immobilization of a novel thermoalkalophilic extracellular amylase from bacilli isolate

“…Immobilized enzymes onto insoluble supports could often display better physiological and biochemical properties such as increased stability and activity in nonaqueous media, enzyme reuse [9][10][11][12]. It has been reported that different support materials have been used for different types of amylases: for ␣-amylases, for example, nitrocellulose membrane [13], calcium alginate beads [3], chitin and chitosan [14], poly (HEMA-GMA) membranes [15] have been preferred, while chitosan microbeads [16] or poly(acrylamide/acrylic acid) resins [17] have been used for ␤-amylases.…”