Stabilization of penicillin G acylase by immobilization on glutaraldehyde-activated chitosan

Abstract

-The objective of this work was to study enzyme immobilization on chitosan activated with glutaraldehyde, aiming to produce a cheap biocatalyst. Two different immobilization strategies were studied: one-point and multipoint covalent attachment to the solid matrix. The multipoint covalent attachment derivative had an 82% immobilization yield. It was 4.9-fold more stable than the free enzyme at 50°C and 4.5-fold more stable than soluble enzyme at pH 10.0. The one-point derivative had an 85% immobilization yield. It was 2.7-fold more stable than the free enzyme at 50°C and 3.8-fold more stable than soluble PGA at pH 10.0. Results indicated that chitosan can be loaded with PGA above 330 IU/g. Intraparticle diffusive effects, however, limited hydrolysis of penicillin G catalyzed by those derivatives at 37°C and 25°C. Operational stability assays were performed and the multipoint derivative exhibited a half-life of 40 hours.

Controlled Protein Hydrolysis with Immobilized Alkaline Endo-Protease

“…Different glutaraldehyde concentrations ranging from 0.25-2% w/v were tested for immobilization of 89L; resin activation was carried out in phosphate buffer (50 mM, pH 7) with immobilization ratio of 1:1, enzyme loading 4mg/ml of resin at 25°C for 16 hrs. It was observed that, enzyme binding increased linearly with glutaraldehyde concentration, but proteolytic activity of immobilized preparation showed initial increase followed by a slight decrease at higher concentrations ( Figure 5), similar trend was observed when acylase was immobilized at various glutaraldehyde concentrations [41]. At 1% glutaraldehyde concentration, highest proteolytic activity was observed without compromising enzyme binding.…”

“…At low glutaraldehyde concentration, all amine groups of support matrix remain unutilized; while high glutaraldehyde concentrations lead to multi point attachment of enzyme. Suitable glutaraldehyde concentration varies with protease being used 1% for mungbean thiol protease [32], 5% for acylase [41] while 2% for papain [42]. Hence, there is need to determine suitable glutaraldehyde concentration, where, higher hydrolytic activity is obtained with minimal enzyme load.…”

Stability Improvement of Immobilized Alkaline Phosphatase Using Chitosan Nanoparticles

“…In a study performed by Kamburov et al (2011) on covalent immobilization of trypsin on chitosan macrobeads, immobilization led to the increase of the enzyme heat resistance. Adriano et al (2005) indicated that the immobilization of penicillin G on chitosan activated by glutaraldehyde can increase the stability of the enzyme 4.9-fold at 50 °C and 4.5-fold at pH 10.0. Kuo et al (2012) immobilized lipase on chitosan-coated Fe 3 O 4 nanoparticles activated with EDC as coupling agent.…”

NANOBIOCATALYTIC SYSTEMS BASED ON LIPASE-Fe3O4 AND CONVENTIONAL SYSTEMS FOR ISONIAZID SYNTHESIS: A COMPARATIVE STUDY

“…A wide variety of immobilization techniques may be employed in order to reduce these operational problems and improve the catalytic activity and ability of these enzymes. It is possible to vary the nature of the immobilized derivative in order to design efficient biocatalytic processes (Adriano et al, 2005;Mohy Eldin et al, 2000). Vol.…”