Immobilization of Brassica oleracea chlorophyllase 1 (BoCLH1) and Candida rugosa lipase (CRL) in magnetic alginate beads: an enzymatic evaluation in the corresponding proteins

Enhanced Enzymatic Performance of β-Mannanase Immobilized on Calcium Alginate Beads for the Generation of Mannan Oligosaccharides

Mannan oligosaccharides (MOSs) are excellent prebiotics that are usually obtained via the enzymatic hydrolysis of mannan. In order to reduce the cost of preparing MOSs, immobilized enzymes that demonstrate good performance, require simple preparation, and are safe, inexpensive, and reusable must be developed urgently. In this study, β-mannanase was immobilized on calcium alginate (CaAlg). Under the optimal conditions of 320 U enzyme addition, 1.6% sodium alginate, 2% CaCl2, and 1 h of immobilization time, the immobilization yield reached 68.3%. The optimum temperature and pH for the immobilized β-mannanase (Man-CaAlg) were 75 °C and 6.0, respectively. The Man-CaAlg exhibited better thermal stability, a high degree of pH stability, and less substrate affinity than free β-mannanase. The Man-CaAlg could be reused eight times and retained 70.34% of its activity; additionally, the Man-CaAlg showed 58.17% activity after 30 days of storage. A total of 7.94 mg/mL of MOSs, with 4.94 mg/mL of mannobiose and 3.00 mg/mL of mannotriose, were generated in the oligosaccharide production assay. It is believed that this convenient and safe strategy has great potential in the important field of the use of immobilized β-mannanase for the production of mannan oligosaccharides.

In Vitro and In Vivo Evaluation of Epidermal Growth Factor (EGF) Loaded Alginate-Hyaluronic Acid (AlgHA) Microbeads System for Wound Healing

The management of skin injuries is one of the most common concerns in medical facilities. Different types of biomaterials with effective wound-healing characteristics have been studied previously. In this study, we used alginate (Alg) and hyaluronic acid (HA) composite (80:20) beads for the sustained release of epidermal growth factor (EGF) delivery. Heparin crosslinked AlgHA beads showed significant loading and entrapment of EGF. Encapsulated beads demonstrated biocompatibility with rat L929 cells and significant migration at the concentration of AlgHAEGF100 and AlgHAEGF150 within 24 h. Both groups significantly improved the expression of Fetal Liver Kinase 1 (FLK-1) along with the Intercellular Adhesion Molecule-1 (ICAM-1) protein in rat bone Mesenchymal stem cells (rbMSCs). In vivo assessment exhibited significant epithelialization and wound closure gaps within 2 weeks. Immunohistochemistry shows markedly significant levels of ICAM-1, FLK-1, and fibronectin (FN) in the AlgHAEGF100 and AlgHAEGF150 groups. Hence, we conclude that the EGF-loaded alginate-hyaluronic acid (AlgHA) bead system can be used to promote wound healing.

Characterization of lipase from Candida rugosa entrapped in alginate beads to enhance its thermal stability and recyclability

Development of a simple method to efficiently immobilize lipase ensuring its stability and activity in water even at high temperatures.

Ex situ and in situ Magnetic Phase Synthesised Magneto-Driven Alginate Beads

Biocompatible magnetic hydrogels provide a great source of synthetic materials, which facilitate remote stimuli, enabling safer biological and environmental applications. Prominently, the ex situ and in situ magnetic phase integration is used to fabricate magneto-driven hydrogels, exhibiting varied behaviours in aqueous media. Therefore, it is essential to understand their physicochemical properties to target the best material for each application. In this investigation, three different types of magnetic alginate beads were synthesised. First, by direct, ex situ, calcium chloride gelation of a mixture of Fe₃O₄ nanoparticles with an alginate solution. Second, by in situ synthesis of Fe₃O₄ nanoparticles inside of the alginate beads and third, by adding an extra protection alginate layer on the in situ synthesised Fe₃O₄ nanoparticles alginate beads. The three types of magnetic beads were chemically and magnetically characterised. It was found that they exhibited particular stability to different pH and ionic strength conditions in aqueous solution. These are essential properties to be controlled when used for magneto-driven applications such as targeted drug delivery and water purification. Therefore, this fundamental study will direct the path to the selection of the best magnetic bead synthesis protocol according to the defined magneto-driven application.

Microfluidic Synthesis of Vinblastine-Loaded Multifunctional Particles for Magnetically Responsive Controlled Drug Release

Vinblastine (VBL) is a major chemotherapeutic drug; however, in some cases, it may cause severe side effects in patients with cancer. Designing a novel VBL pharmaceutical formulation is a crucial and emerging concern among researchers for reducing the use of VBL. This study developed a stimuli-responsive controlled VBL drug release system from magnetically sensitive chitosan capsules. A magnetically responsive controlled drug release system was designed by embedding superparamagnetic iron oxide (SPIO) nanoparticles (NPs) in a chitosan matrix and an external magnet. In addition, droplet microfluidics, which is a novel technique for producing polymer spheres, was used for manufacturing monodispersed chitosan microparticles. The prepared VBL and SPIO NPs-loaded chitosan microparticles were characterized and analyzed using Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, a superconducting quantum interference device, and a biocompatibility test. The drug encapsulation efficiency was 67%-69%. The in vitro drug release test indicated that the VBL could be 100% released from chitosan composite particles in 80-130 min under magnetic stimulation. The pulsatile magnetically triggered tests showed individual and distinctive controlled release patterns. Thus, the timing and dose of VBL release was controllable by an external magnet. The results presume that using a magnetically responsive controlled drug release system offers a valuable opportunity for VBL drug delivery, where the delivery system is an active participant, rather than a passive vehicle, in the optimization of cancer treatment. The proposed actively targeted magnetic drug delivery system offers many advantages over conventional drug delivery systems by improving the precision and timing of drug release, easy operation, and higher compliance for pharmaceutical applications.

Immobilization of Chlamydomonas reinhardtii CLH1 on APTES-Coated Magnetic Iron Oxide Nanoparticles and Its Potential in the Production of Chlorophyll Derivatives

Recombinant Chlamydomonas reinhardtii chlorophyllase 1 (CrCLH1) that could catalyze chlorophyll hydrolysis to chlorophyllide and phytol in vitro was successfully expressed in Escherichia coli. The recombinant CrCLH1 was immobilized through covalent binding with a cubic (3-aminopropyl) triethoxysilane (APTES) coating on magnetic iron oxide nanoparticles (MIONPs), which led to markedly improved enzyme performance and decreased biocatalyst costs for potential industrial application. The immobilized enzyme exhibited a high immobilization yield (98.99 ± 0.91 mg/g of gel) and a chlorophyllase assay confirmed that the immobilized recombinant CrCLH1 retained enzymatic activity (722.3 ± 50.3 U/g of gel). Biochemical analysis of the immobilized enzyme, compared with the free enzyme, showed higher optimal pH and pH stability for chlorophyll-a hydrolysis in an acidic environment (pH 3-5). In addition, compared with the free enzyme, the immobilized enzyme showed higher activity in chlorophyll-a hydrolysis in a high temperature environment (50-60 °C). Moreover, the immobilized enzyme retained a residual activity of more than 64% of its initial enzyme activity after 14 cycles in a repeated-batch operation. Therefore, APTES-coated MIONP-immobilized recombinant CrCLH1 can be repeatedly used to lower costs and is potentially useful for the industrial production of chlorophyll derivatives.

CRGO/alginate microbeads: an enzyme immobilization system and its potential application for a continuous enzymatic reaction

Hybrid bio-inorganic microbeads composed of CRGO–enzyme and alginate exhibited better stability and higher environmental tolerance, which can be used in a continuous fixed-bed enzymatic reaction.