Enzyme immobilization: an update (original) (raw)

An Overview of Enzyme Immobilization

2017

The use of enzymes as biological catalysts has gained increasing importance in industries. Although enzymes can be obtained from plant and animal origin, microbial enzymes have several advantages over enzymes derived from other sources. Due to the high cost of separation of enzymes from product, the instability of enzymes and reduced enzyme activity, several strategies are now been explored to develop immobilized enzymes. Immobilized enzymes have been produced by cell immobilization techniques. Immobilized enzymes have found several industrial applications where they provide the advantages of easy separation of the enzyme from the product, reuse of the enzyme, convenient handling, high stability under extreme physical and chemical conditions, being applicable for all types of reactors with varied interior design, and provides easier process control. However, despite these advantages, enzyme immobilization techniques continue to pose some challenges. These challenges notwithstanding,...

2 3 Enzyme immobilization: an update

Compared to free enzymes in solution, immobilized enzymes are more robust and more resistant to environmental changes. More importantly, the heterogeneity of the immobilized enzyme systems allows an easy recovery of both enzymes and products, multiple re-use of enzymes, continuous operation of enzymatic processes, rapid termination of reactions, and greater variety of bioreactor designs. This paper is a review of the recent literatures on enzyme immobilization by various techniques, the need for immobilization and different applications in industry, covering the last two decades. The most recent papers, patents, and reviews on immobilization strategies and application are reviewed.

Enzyme immobilization: an overview on techniques and support materials

The current demands of the world's biotechnological industries are enhancement in enzyme productivity and development of novel techniques for increasing their shelf life. These requirements are inevitable to facilitate large-scale and economic formulation. Enzyme immobilization provides an excellent base for increasing availability of enzyme to the substrate with greater turnover over a considerable period of time. Several natural and synthetic supports have been assessed for their efficiency for enzyme immobilization. Nowadays, immobilized enzymes are preferred over their free counterpart due to their prolonged availability that curtails redundant downstream and purification processes. Future investigations should endeavor at adopting logistic and sensible entrapment techniques along with innovatively modified supports to improve the state of enzyme immobilization and provide new perspectives to the industrial sector.

Current Trend in Enzyme Immobilization: A Review

2013

The term "immobilized enzymes" refers to "enzymes physically confined or localized in a certain defined region of space with retention of their catalytic activities, and which can be used repeatedly and continuously". Besides the application in industrial processes, the immobilization techniques are the basis for making a number of biotechnological products with applications in diagnostics, antibiotic production, bioremediation and biosensors. The major components of an immobilized enzyme system are the enzyme, the matrix, and the mode of attachment. The enzymes can be attached to the support by interactions ranging from reversible physical adsorption and ionic linkages to stable covalent bonds. As a consequence of enzyme immobilization, some properties such as catalytic activity or thermal stability become altered. However, immobilized enzymes possess the capability of reuse, low cost of production and have many industrial and medical applications. The concept o...

METHODS, APPLICATIONS OF IMMOBILIZED ENZYMES-A MINI REVIEW

Reports on chemical immobilization of proteins and enzymes first appeared in the 1960s. Since then, immobilized proteins and enzymes have been widely used in the processing of variety of products and increasingly used in the field of medicine. Here, we present a review of recent developments in immobilized enzyme use in medicine. Immobilized enzymes are widely used for variety of applications. Based on the type of application, the method of immobilization and support material can be selected. The immobilized enzymes can be separated from the reaction mixture and reused and also immobilized in order to prevent the enzyme from being exposed to harsh conditions, high temperature, surfactants, and oxidizing agents etc. the immobilized enzymes are also widely used in food industry, pharmaceutical industry, bioremediation, detergent industry, textile industry, etc. Enzyme immobilization improves the operational stability and is also due to the increased enzyme loading which causes the controlled diffusion. Several hundreds of enzymes are immobilized and used for various large scale industries. Immobilization technique reduces the effluent treatment costs and this paper reviews the methods and applications of immobilized enzymes.

Enzyme Immobilization: Research and Studies

https://www.ijrrjournal.com/IJRR\_Vol.3\_Issue.7\_July2016/Abstract\_IJRR006.html, 2016

The synthesis of many chemicals needs high temperature and pressure. Many chemicals like ethanol, amino acids, citric acids, nitrates, nitrites, fine chemicals, essential compounds can be synthesized by biological pathways. Enzyme catalyzed reactions provide huge boost to the efforts concentrated on cost effective and environment friendly technology. Immobilization of enzyme has advantages such as high thermal and operational stability, improved pH stability. Various investigators have carried out investigations to study effect of immobilization on enzyme activities. The current review summarizes research and studies on enzyme immobilization.

Enzyme immobilization and its applications in food processing: A review

International Journal of Chemical Studies

The "immobilized enzymes" are the enzymes physically confined or localized in a certain defined region of space with retention of their catalytic activities which can be used repeatedly and continuously. Enzyme immobilization provides an excellent base for increasing availability of enzyme to the substrate with greater turnover over a considerable period of time. Immobilized enzymes are preferred over their free counterpart due to their prolonged availability that reduces redundant downstream and purification processes. The enzymes can be attached to the support by interactions ranging from reversible physical adsorption and ionic linkages to stable covalent bonds. The choice of the most appropriate immobilization technique depends on the nature of the enzyme and the carrier. Such techniques produce immobilized enzymes of varying stability due to changes in the surface microenvironment and degree of multipoint attachment. The industrial applications of immobilised enzymes are progressively increasing. Immobilized enzymes find use in a number of biotechnological products with applications in diagnostics, bio affinity chromatography, and biosensors. Immobilised enzymes find wide applications in the food industry. With these immobilised enzymes, it is possible to obtain different types of sugar syrups, lactose free milk, clarified and debittered juices and wines. Immobilised enzymes can be employed for the production of different active packaging material like oxygen scavenging, anti-microbial films. However, commercialization of immobilized enzymes is still at a slower pace because of their costs and storage problems. Research should be focused to overcome the current limitations related to immobilization techniques, so as to expand the horizon for all-round application. In future, immobilized enzymes are going to play a vital role in various industries including pharmaceuticals, chemicals, food and fuel.

IMMOBILIZATION OF ENZYMES IN THEIR ECONOMIC REUSE-A REVIEW

Enzyme Immobilization has attracted much attention in recent years with proposed applications besides in industrial process these are basis for making of biotechnological products with applications in diagnostics, bioaffinity chromatography, and biosensors. The term immobilized enzymes refers to enzymes physically confined in a certain defined region of space with retention of their catalytic activities, and which can be used repeatedly and continuously. Immobilization stabilizes the structure of the enzyme, thereby allowing their applications even under harsh environmental conditions of pH, temperature, thermal denaturation and its economic reuse under stabilized conditions. Here the authors discuss various techniques of immobilization and consequences of enzyme immobilization such as catalytic activity, thermal stability and kinetics of immobilized enzymes. The major components of an immobilized enzyme system are the enzyme, the matrix, and the mode of attachment. The enzyme can be attached to the support by interactions ranging from reversible physical adsorption, stable covalent bonds, ionic linkage or entrapment.

Immobilization of Enzymes: A Literature Survey

Methods in molecular biology, 2013

The term immobilized enzymes refers to "enzymes physically confi ned or localized in a certain defi ned region of space with retention of their catalytic activities, and which can be used repeatedly and continuously." Immobilized enzymes are currently the subject of considerable interest because of their advantages over soluble enzymes. In addition to their use in industrial processes, the immobilization techniques are the basis for making a number of biotechnology products with application in diagnostics, bioaffi nity chromatography, and biosensors. At the beginning, only immobilized single enzymes were used, after 1970s more complex systems including two-enzyme reactions with cofactor regeneration and living cells were developed. The enzymes can be attached to the support by interactions ranging from reversible physical adsorption and ionic linkages to stable covalent bonds. Although the choice of the most appropriate immobilization technique depends on the nature of the enzyme and the carrier, in the last years the immobilization technology has increasingly become a matter of rational design. As a consequence of enzyme immobilization, some properties such as catalytic activity or thermal stability become altered. These effects have been demonstrated and exploited. The concept of stabilization has been an important driving force for immobilizing enzymes. Moreover, true stabilization at the molecular level has been demonstrated, e.g., proteins immobilized through multipoint covalent binding.

Enzyme Immobilization: The Quest for Optimum Performance

Advanced Synthesis & Catalysis, 2007

Immobilization is often the key to optimizing the operational performance of an enzyme in industrial processes, particularly for use in non-aqueous media. Different methods for the immobilization of enzymes are critically reviewed. The methods are divided into three main categories, viz. (i) binding to a prefabricated support (carrier), (ii) entrapment in organic or inorganic polymer matrices, and (iii) cross-linking of enzyme molecules. Emphasis is placed on relatively recent developments, such as the use of novel supports, e.g., mesoporous silicas, hydrogels, and smart polymers, novel entrapment methods and cross-linked enzyme aggregates (CLEAs).