The Experts below are selected from a list of 25029 Experts worldwide ranked by ideXlab platform
Mansoor M Amiji - One of the best experts on this subject based on the ideXlab platform.
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Enzyme Immobilization in novel alginate chitosan core shell microcapsules
Biomaterials, 2004Co-Authors: Ehab S Taqieddin, Mansoor M AmijiAbstract:Abstract Alginate–chitosan core-shell microcapsules were prepared in order to develop a biocompatible matrix for Enzyme Immobilization, where the protein is retained either in a liquid or solid core and the shell allows permeability control over substrates and products. The permeability coefficients of different molecular weight compounds (vitamin B2, vitamin B12, and myoglobin) were determined through sodium tripolyphosphate (Na-TPP)-crosslinked chitosan membrane. The microcapsule core was formed by crosslinking sodium alginate with either calcium or barium ions. The crosslinked alginate core was uniformly coated with a chitosan layer and crosslinked with Na-TPP. In the case of calcium alginate, the phosphate ions of Na-TPP were able to extract the calcium ions from alginate and liquefy the core. A model Enzyme, β -galactosidase, was immobilized in the alginate core and the catalytic activity was measured with o -nitrophenyl- β - d -galactopyranoside (ONPG). Change in the activity of free and immobilized Enzyme was determined at three different temperatures. Na-TPP crosslinked chitosan membranes were found to be permeable to solutes of up to 17,000 Da molecular weight. The Enzyme loading efficiency was higher in the barium alginate core (100%) as compared to the calcium alginate core (60%). The rate of ONPG conversion to o -nitrophenol was faster in the case of calcium alginate–chitosan microcapsules as compared to barium alginate–chitosan microcapsules. Barium alginate–chitosan microcapsules, however, did improve the stability of the Enzyme at 37°C relative to calcium alginate–chitosan microcapsules or free Enzyme. This study illustrates a new method of Enzyme Immobilization for biotechnology applications using liquid or solid core and shell microcapsule technology.
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Enzyme Immobilization in novel alginate chitosan core shell microcapsules
Biomaterials, 2004Co-Authors: Ehab S Taqieddin, Mansoor M AmijiAbstract:Alginate-chitosan core-shell microcapsules were prepared in order to develop a biocompatible matrix for Enzyme Immobilization, where the protein is retained either in a liquid or solid core and the shell allows permeability control over substrates and products. The permeability coefficients of different molecular weight compounds (vitamin B2, vitamin B12, and myoglobin) were determined through sodium tripolyphosphate (Na-TPP)-crosslinked chitosan membrane. The microcapsule core was formed by crosslinking sodium alginate with either calcium or barium ions. The crosslinked alginate core was uniformly coated with a chitosan layer and crosslinked with Na-TPP. In the case of calcium alginate, the phosphate ions of Na-TPP were able to extract the calcium ions from alginate and liquefy the core. A model Enzyme, beta-galactosidase, was immobilized in the alginate core and the catalytic activity was measured with o-nitrophenyl-beta-D-galactopyranoside (ONPG). Change in the activity of free and immobilized Enzyme was determined at three different temperatures. Na-TPP crosslinked chitosan membranes were found to be permeable to solutes of up to 17,000Da molecular weight. The Enzyme loading efficiency was higher in the barium alginate core (100%) as compared to the calcium alginate core (60%). The rate of ONPG conversion to o-nitrophenol was faster in the case of calcium alginate-chitosan microcapsules as compared to barium alginate-chitosan microcapsules. Barium alginate-chitosan microcapsules, however, did improve the stability of the Enzyme at 37 degrees C relative to calcium alginate-chitosan microcapsules or free Enzyme. This study illustrates a new method of Enzyme Immobilization for biotechnology applications using liquid or solid core and shell microcapsule technology.
Manuel Pinelo - One of the best experts on this subject based on the ideXlab platform.
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multi faceted strategy based on Enzyme Immobilization with reactant adsorption and membrane technology for biocatalytic removal of pollutants a critical review
Biotechnology Advances, 2019Co-Authors: Jakub Zdarta, Anne S Meyer, Teofil Jesionowski, Manuel PineloAbstract:Abstract In the modern era, the use of sustainable, environmentally friendly alternatives for removal of recalcitrant pollutants in streams resulting from industrial processes is of key importance. In this context, biodegradation of phenolic compounds, pharmaceuticals and dyes in wastewater by using oxidoreductases offers numerous benefits. Tremendous research efforts have been made to develop novel, hybrid strategies for simultaneous Immobilization of oxidoreductase and removal of toxic compounds. The use of support materials with the options for combining Enzyme Immobilization with adsorption technology focused on phenolic pollutants and products of biocatalytic conversion seems to be of particular interest. Application of enzymatic reactors based on immobilized oxidoreductases for coupling Enzyme-aided degradation and membrane separation also attract still growing attention. However, prior selection of the most suitable support/sorbent material and/or membrane as well as operational mode and Immobilization technique is required in order to achieve high removal efficiency. Thus, in the framework of this review, we present an overview of the impact of support/sorbent material on the catalytic properties of immobilized Enzymes and sorption of pollutants as well as parameters of membranes for effective bioconversion and separation. Finally, future perspectives of the use of processes combining Enzyme Immobilization and sorption technology as well as application of enzymatic reactors for removal of environmental pollutants are discussed.
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A general overview of support materials for Enzyme Immobilization: Characteristics, properties, practical utility
Catalysts, 2018Co-Authors: Jakub Zdarta, Anne S Meyer, Teofil Jesionowski, Manuel PineloAbstract:In recent years, Enzyme Immobilization has been presented as a powerful tool for the improvement of Enzyme properties such as stability and reusability. However, the type of support material used plays a crucial role in the Immobilization process due to the strong effect of these materials on the properties of the produced catalytic system. A large variety of inorganic and organic as well as hybrid and composite materials may be used as stable and efficient supports for biocatalysts. This review provides a general overview of the characteristics and properties of the materials applied for Enzyme Immobilization. For the purposes of this literature study, support materials are divided into two main groups, called Classic and New materials. The review will be useful in selection of appropriate support materials with tailored properties for the production of highly effective biocatalytic systems for use in various processes.
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cascade catalysis in membranes with Enzyme Immobilization for multi enzymatic conversion of co2 to methanol
New Biotechnology, 2015Co-Authors: Jianquan Luo, Anne S Meyer, Ramona Valentina Mateiu, Manuel PineloAbstract:Facile co-Immobilization of Enzymes is highly desirable for bioconversion methods involving multi-enzymatic cascade reactions. Here we show for the first time that three Enzymes can be immobilized in flat-sheet polymeric membranes simultaneously or separately by simple pressure-driven filtration (i.e. by directing membrane fouling formation), without any addition of organic solvent. Such co-Immobilization and sequential Immobilization systems were examined for the production of methanol from CO2 with formate dehydrogenase (FDH), formaldehyde dehydrogenase (FaldDH) and alcohol dehydrogenase (ADH). Enzyme activity was fully retained by this non-covalent Immobilization strategy. The two Immobilization systems had similar catalytic efficiencies because the second reaction (formic acid→formaldehyde) catalyzed by FaldDH was found to be the cascade bottleneck (a threshold substrate concentration was required). Moreover, the trade-off between the mitigation of product inhibition and low substrate concentration for the adjacent Enzymes probably made the co-Immobilization meaningless. Thus, sequential Immobilization could be used for multi-enzymatic cascade reactions, as it allowed the operational conditions for each single step to be optimized, not only during the Enzyme Immobilization but also during the reaction process, and the pressure-driven mass transfer (flow-through mode) could overcome the diffusion resistance between Enzymes. This study not only offers a green and facile Immobilization method for multi-enzymatic cascade systems, but also reveals the reaction bottleneck and provides possible solutions for the bioconversion of CO2 to methanol.
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Enzyme Immobilization by fouling in ultrafiltration membranes impact of membrane configuration and type on flux behavior and biocatalytic conversion efficacy
Biochemical Engineering Journal, 2014Co-Authors: Anne S Meyer, Gunnar Eigil Jonsson, Manuel PineloAbstract:Abstract Enzyme-Immobilization in membranes accomplished by fostering membrane fouling was evaluated. Four different membrane configurations and five membranes were compared for Immobilization of alcohol dehydrogenase (ADH) in terms of Enzyme loading, permeate flux and final biocatalytic conversion. The membrane configuration impacted the efficiency of the Enzyme-Immobilization as well as the biocatalytic-membrane reaction, and the “sandwich mode”, with an extra polypropylene support above the membrane skin layer, worked best due to its high flux and stable conversion. Among the membranes, a GR51PP polysulphone membrane allowed for the highest flux during the reaction with the Enzyme-immobilized membrane. At the same time, the lowest Enzyme loading and low reaction stability were achieved for this membrane. Satisfactory Enzyme loadings, stable conversions, but low flux rates were obtained for the PLTK and PLGC regenerated cellulose membranes. With these two highly hydrophilic membranes, the ADH Enzyme activity was fully retained even after 24 h of storage of the membrane. Filtration blocking and resistance models were used to analyze the fouling/Immobilization mechanisms and give explanations for the different results. The work confirms that fouling-induced Enzyme Immobilization is a promising option for enhancing biocatalytic productivity, and highlights the significance of the membrane type and configuration for optimal performance.
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fouling induced Enzyme Immobilization for membrane reactors
Bioresource Technology, 2013Co-Authors: Anne S Meyer, Gunnar Eigil Jonsson, Manuel PineloAbstract:A simple Enzyme Immobilization method accomplished by promoting membrane fouling formation is proposed. The Immobilization method is based on adsorption and entrapment of the Enzymes in/on the membrane. To evaluate the concept, two membrane orientations, skin layer facing feed (normal mode) and support layer facing feed (reverse mode), were used to immobilize alcohol dehydrogenase (ADH, EC 1.1.1.1) and glutamate dehydrogenase (GDH, EC 1.4.1.3), respectively. The nature of the fouling in each mode was determined by filtration fouling models. The permeate flux was larger in the normal mode, but the reverse mode allowed for higher Enzyme loading and stability, and irreversible fouling (i.e. pore blocking) developed more readily in the support structure than in the skin layer. Compared with an enzymatic membrane reactor (EMR) with free Enzymes, the novel EMR with Enzymes immobilized in membrane support improved the Enzyme reusability (especially for ADH), and reduced the product inhibition (especially for GDH).
Zhongyi Jiang - One of the best experts on this subject based on the ideXlab platform.
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nanoporous phyllosilicate assemblies for Enzyme Immobilization
ACS Applied Bio Materials, 2019Co-Authors: Shuang Mei, Jiafu Shi, Zhongyi Jiang, Shaohua Zhang, Yue WangAbstract:Physical/chemical adsorption is well-known as a facile and effective method for Enzyme Immobilization, while ideal adsorbents with a high structural stability, high loading capacity, and low leaching ratio are still under exploration. In this study, nanoporous assemblies of two-dimensional (2D) copper phyllosilicate (L-CuSiO3) are prepared as an adsorbent to immobilize horseradish peroxidase (HRP) for phenol-containing wastewater treatment. Specifically, the robust chemical bonds of Si–O–Si and Si–O–Cu in L-CuSiO3 ensure its superior structural stability; the well-developed porous structure endows L-CuSiO3 assemblies with a high specific surface area of 611.7 cm3 g–1, which enables a fast and high Enzyme loading of 140 mg g–1 within 4 h, and the well-distributed Cu(II) ions ensure the stable attachment of Enzyme through Cu(II)-arginine (in HRP) coordination with a leaching ratio less than 10%. Meanwhile, the scaling assembly of L-CuSiO3 renders the resultant biocatalyst (HRP-loaded L-CuSiO3 assemblies) ea...
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Nanoporous Phyllosilicate Assemblies for Enzyme Immobilization
2019Co-Authors: Shuang Mei, Jiafu Shi, Shaohua Zhang, Yue Wang, Zhongyi JiangAbstract:Physical/chemical adsorption is well-known as a facile and effective method for Enzyme Immobilization, while ideal adsorbents with a high structural stability, high loading capacity, and low leaching ratio are still under exploration. In this study, nanoporous assemblies of two-dimensional (2D) copper phyllosilicate (L-CuSiO3) are prepared as an adsorbent to immobilize horseradish peroxidase (HRP) for phenol-containing wastewater treatment. Specifically, the robust chemical bonds of Si–O–Si and Si–O–Cu in L-CuSiO3 ensure its superior structural stability; the well-developed porous structure endows L-CuSiO3 assemblies with a high specific surface area of 611.7 cm3 g–1, which enables a fast and high Enzyme loading of 140 mg g–1 within 4 h, and the well-distributed Cu(II) ions ensure the stable attachment of Enzyme through Cu(II)-arginine (in HRP) coordination with a leaching ratio less than 10%. Meanwhile, the scaling assembly of L-CuSiO3 renders the resultant biocatalyst (HRP-loaded L-CuSiO3 assemblies) ease-of-recycling performance. Given the above features, the HRP-loaded L-CuSiO3 assemblies exhibit a better stability and 2-fold higher activity by contrast with HRP adsorbed on conventional mesoporous SiO2 and SiO2 nanoparticles, and it also acted as an efficient bioreactor in the application of catalytical removal of phenol pollutants from wastewater. Our L-CuSiO3 assemblies show great potential in Immobilization of Enzymes for industrial biocatalysis
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One-pot fabrication of chitin-shellac composite microspheres for efficient Enzyme Immobilization
Journal of Biotechnology, 2018Co-Authors: Shuang Mei, Pingping Han, Jiafu Shi, Lei Tang, Zhongyi JiangAbstract:Abstract In this study, all-natural composite microspheres were fabricated through adding shellac into chitin solution followed by self-assembly via thermally-induced phase separation. The pore structure of the composite microspheres was altered into wedge-shape from ink-bottle-shape of the chitin microspheres, whereas, the crystalline structure of these two kinds of microspheres remained unaltered. The as-fabricated chitin-shellac composite microspheres were used for Enzyme Immobilization through adsorption. And yeast alcohol dehydrogenase (YADH) was chosen as the model Enzyme, which is a multimer consisting of 4 subunits. The loading capacity of the as-prepared composite microspheres was up to 79.0 mg/g (Enzyme/carrier). The immobilized Enzyme exhibited a comparable catalytic activity compared to its free counterpart and maintained 49.3% of its initial activity after 54 days’ storage at 4 °C while the free Enzyme lost all its activity.
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monolithic biocatalytic systems with enhanced stabilities constructed through biomimetic silicification induced Enzyme Immobilization on rgo feooh hydrogel
Biochemical Engineering Journal, 2017Co-Authors: Dong Yang, Jiafu Shi, Zhongyi Jiang, Xueyan Wang, Shaohua Zhang, Jingjing ZhaoAbstract:Abstract In this study, we present a green and facile method of utilizing biomimetic silicification to trigger Enzyme Immobilization on the surface of the rGO/FeOOH hydrogel for constructing stable monolithic biocatalytic systems. In brief, the rGO/FeOOH hydrogel is firstly prepared through metal ion-induced reduction/assembly of graphene oxide (GO) nanosheets, which is then utilized to adsorb cationic polyethyleneimine (PEI). This cationic PEI, as the mineralization-inducing agent, catalyzes the condensation of silicate to form silica (biomimetic silicification) on the rGO surface, where Enzyme is simultaneously entrapped. The resultant rGO/FeOOH/silica hydrogel shows an extraordinary three-dimensional (3D) porous structure. The silica content on the rGO surface can be facilely tailored through changing the silica precursor concentration. Combined with monolithic macroscale of the rGO/FeOOH/silica hydrogel, the acquired monolithic biocatalytic systems display easy recyclability and elevated pH/thermal/recycling/storage stabilities during the catalytic production of 6-aminopenicillanic acid (6-APA) in comparison to Enzyme in free form and Enzyme adsorbed on rGO/FeOOH hydrogel. Notably, the activity can be retained up to 93.3% of its initial activity after 11 reaction cycles for our biocatalytic systems.
Ehab S Taqieddin - One of the best experts on this subject based on the ideXlab platform.
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Enzyme Immobilization in novel alginate chitosan core shell microcapsules
Biomaterials, 2004Co-Authors: Ehab S Taqieddin, Mansoor M AmijiAbstract:Abstract Alginate–chitosan core-shell microcapsules were prepared in order to develop a biocompatible matrix for Enzyme Immobilization, where the protein is retained either in a liquid or solid core and the shell allows permeability control over substrates and products. The permeability coefficients of different molecular weight compounds (vitamin B2, vitamin B12, and myoglobin) were determined through sodium tripolyphosphate (Na-TPP)-crosslinked chitosan membrane. The microcapsule core was formed by crosslinking sodium alginate with either calcium or barium ions. The crosslinked alginate core was uniformly coated with a chitosan layer and crosslinked with Na-TPP. In the case of calcium alginate, the phosphate ions of Na-TPP were able to extract the calcium ions from alginate and liquefy the core. A model Enzyme, β -galactosidase, was immobilized in the alginate core and the catalytic activity was measured with o -nitrophenyl- β - d -galactopyranoside (ONPG). Change in the activity of free and immobilized Enzyme was determined at three different temperatures. Na-TPP crosslinked chitosan membranes were found to be permeable to solutes of up to 17,000 Da molecular weight. The Enzyme loading efficiency was higher in the barium alginate core (100%) as compared to the calcium alginate core (60%). The rate of ONPG conversion to o -nitrophenol was faster in the case of calcium alginate–chitosan microcapsules as compared to barium alginate–chitosan microcapsules. Barium alginate–chitosan microcapsules, however, did improve the stability of the Enzyme at 37°C relative to calcium alginate–chitosan microcapsules or free Enzyme. This study illustrates a new method of Enzyme Immobilization for biotechnology applications using liquid or solid core and shell microcapsule technology.
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Enzyme Immobilization in novel alginate chitosan core shell microcapsules
Biomaterials, 2004Co-Authors: Ehab S Taqieddin, Mansoor M AmijiAbstract:Alginate-chitosan core-shell microcapsules were prepared in order to develop a biocompatible matrix for Enzyme Immobilization, where the protein is retained either in a liquid or solid core and the shell allows permeability control over substrates and products. The permeability coefficients of different molecular weight compounds (vitamin B2, vitamin B12, and myoglobin) were determined through sodium tripolyphosphate (Na-TPP)-crosslinked chitosan membrane. The microcapsule core was formed by crosslinking sodium alginate with either calcium or barium ions. The crosslinked alginate core was uniformly coated with a chitosan layer and crosslinked with Na-TPP. In the case of calcium alginate, the phosphate ions of Na-TPP were able to extract the calcium ions from alginate and liquefy the core. A model Enzyme, beta-galactosidase, was immobilized in the alginate core and the catalytic activity was measured with o-nitrophenyl-beta-D-galactopyranoside (ONPG). Change in the activity of free and immobilized Enzyme was determined at three different temperatures. Na-TPP crosslinked chitosan membranes were found to be permeable to solutes of up to 17,000Da molecular weight. The Enzyme loading efficiency was higher in the barium alginate core (100%) as compared to the calcium alginate core (60%). The rate of ONPG conversion to o-nitrophenol was faster in the case of calcium alginate-chitosan microcapsules as compared to barium alginate-chitosan microcapsules. Barium alginate-chitosan microcapsules, however, did improve the stability of the Enzyme at 37 degrees C relative to calcium alginate-chitosan microcapsules or free Enzyme. This study illustrates a new method of Enzyme Immobilization for biotechnology applications using liquid or solid core and shell microcapsule technology.
Richard A Vaia - One of the best experts on this subject based on the ideXlab platform.
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poly 2 hydroxyethyl methacrylate for Enzyme Immobilization impact on activity and stability of horseradish peroxidase
Biomacromolecules, 2011Co-Authors: Sarah M. Lane, Zhifeng Kuang, Shafi Arifuzzaman, Barry L Farmer, Rajesh R Naik, Jan Genzer, Richard A VaiaAbstract:On the basis of their versatile structure and chemistry as well as tunable mechanical properties, polymer brushes are well-suited as supports for Enzyme Immobilization. However, a robust surface design is hindered by an inadequate understanding of the impact on activity from the coupling motif and Enzyme distribution within the brush. Herein, horseradish peroxidase C (HRP C, 44 kDa), chosen as a model Enzyme, was immobilized covalently through its lysine residues on a N-hydroxysuccinimidyl carbonate-activated poly(2-hydroxyethyl methacrylate) (PHEMA) brush grafted chemically onto a flat impenetrable surface. Up to a monolayer coverage of HRP C is achieved, where most of the HRP C resides at or near the brush−air interface. Molecular modeling shows that lysines 232 and 241 are the most probable binding sites, leading to an orientation of the immobilized HRP C that does not block the active pocket of the Enzyme. Michaelis−Menten kinetics of the immobilized HRP C indicated little change in the Km (Michaelis ...
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poly 2 hydroxyethyl methacrylate for Enzyme Immobilization impact on activity and stability of horseradish peroxidase
Biomacromolecules, 2011Co-Authors: Sarah M. Lane, Zhifeng Kuang, Shafi Arifuzzaman, Barry L Farmer, Rajesh R Naik, Jan Genzer, Jeannie Yom, Richard A VaiaAbstract:On the basis of their versatile structure and chemistry as well as tunable mechanical properties, polymer brushes are well-suited as supports for Enzyme Immobilization. However, a robust surface design is hindered by an inadequate understanding of the impact on activity from the coupling motif and Enzyme distribution within the brush. Herein, horseradish peroxidase C (HRP C, 44 kDa), chosen as a model Enzyme, was immobilized covalently through its lysine residues on a N-hydroxysuccinimidyl carbonate-activated poly(2-hydroxyethyl methacrylate) (PHEMA) brush grafted chemically onto a flat impenetrable surface. Up to a monolayer coverage of HRP C is achieved, where most of the HRP C resides at or near the brush-air interface. Molecular modeling shows that lysines 232 and 241 are the most probable binding sites, leading to an orientation of the immobilized HRP C that does not block the active pocket of the Enzyme. Michaelis-Menten kinetics of the immobilized HRP C indicated little change in the K(m) (Michaelis constant) but a large decrease in the V(max) (maximum substrate conversion rate) and a correspondingly large decrease in the k(cat) (overall catalytic rate). This indicates a loss in the percentage of active Enzymes. Given the relatively ideal geometry of the HRPC-PHEMA brush, the loss of activity is most likely due to structural changes in the Enzyme arising from either secondary constraints imposed by the connectivity of the N-hydroxysuccinimidyl carbonate linking moiety or nonspecific interactions between HRP C and DSC-PHEMA. Therefore, a general Enzyme-brush coupling motif must optimize reactive group density to balance binding with neutrality of surroundings.