Effect of the pH in the formation of β-galactosidase microparticles produced by a spray-drying process

Abstract

The objective of this work was to investigate the influence of pH in the microencapsulation process, using a modified chitosan to microencapsulate the enzyme β-galactosidase, by a spray-drying technique. Structural analysis of the surface of the particles was performed by scanning electron microscopy (SEM), showing that the obtained microparticles have an average diameter smaller than 3.5 μm and in general a regular shape. The activity of the enzyme was studied by spectrophotometric methods using the substrate O-nitrophenyl-β,D-galactopyranoside (ONPG). The parameters of Michaelis-Menten were calculated. The value of Km decreases with the decrease of the pH, which can be associated to an increase of the affinity between the enzyme and substrate to smaller pH's. The highest value of the parameter Vmax, representing the maximum reaction rate at a given enzyme concentration, was obtained at pH 6.

Development of enzymatically-active bacterial cellulose membranes through stable immobilization of an engineered β-galactosidase

“…Furthermore, the different structure of water molecules within the polymeric matrix may also modulate enzyme kinetics, as proposed by Burgos et al [47]. Enzyme inactivation upon immobilization has been extensively described with diverse techniques and enzymes [3,5,48].…”

“…Enzyme immobilization provides advantages by reducing operational costs, prolonging enzyme lifetime, increasing enzyme stability and facilitating their recovery and reuse [1]. Specifically, immobilization of -galactosidases has attracted a great deal of interest, as they are biotechnologically relevant enzymes with important applications in health and food industries [2][3][4][5]. -Galactosidases (EC 3.2.1.23) are glycosidases that hydrolyse terminal non-reducing -D-galactose residues from di-, oligo-and conjugated-saccharides.…”

Encapsulation of lactase in Ca(II)-alginate beads: Effect of stabilizers and drying methods

“…Lactose intolerance is a condition in which people's ability to digest lactose is decreased, due to insufficiency or lack of the enzyme called galactosidase (lactase) in the small intestines, which is crucial to break lactose down into its monosaccharides, suffering several digestive syndromes (Heaney, 2013;Misselwitz et al, 2013). People who suffer this alteration should consume lactose free products or include the enzyme as a supplement (Zhang, Zhang, & McClements, 2017;Estevinho, Ramos, & Rocha, 2015). However, lactase cannot be consumed in its free form due to its instability against to thermal, chemical and mechanical effects, so it, the encapsulation of the enzyme in biopolymers matrices (Wahba, 2016) could not only maintain its catalytic activity but also opens the possibility of its incorporation and consumption inside different foods (Wu et al, 2013).…”

Stabilization and application of spray-dried tannase from Aspergillus fumigatus CAS21 in the presence of different carriers

“…Factors, such as dryer types, resident time, chamber size, and geometry, affect the performance of the drying process and, consequently, the quality of the final product and its physico-chemical properties (Costa et al 2015;Keshani et al 2015). The yield is also affected by the adherence of the product onto the walls of the drying chamber of a cyclone dryer or by elutriation (Estevinho et al 2015;Abdel-Madeeg et al 2019). When maltodextrin was used as adjuvant, a considerable amount of the powder was retained on the walls of the cyclone dryer.…”