With the progress of enzyme separation and purification methods and the development of immobilization technology, the application form of enzymes is also constantly improving. As for an enzyme reactor, due to differences in specific targets and contents, the types of enzyme reactions used, the nature of the reactions, the scale, and the requirements are also different. Therefore, it is of great importance to choose the right one. Listed below are several common enzyme application forms:
Whole cell
This type of application is generally used in the process of material conversion, three-waste treatment, and the like, and mainly utilizes intracellular enzymes to function. For example, the metabolic activities of microorganisms are used to produce products of different complexity, such as antibiotics, vitamins, and the like. The conversion of these products is mostly done at the same time as the growth of microorganisms or at the later stage of growth, through their metabolic activities, and therefore, the combined action of multiple enzymes is often involved. Of course, it is also possible to use the action of a single enzyme, which is not related to the growth and metabolic activity of the microorganism itself, and it is possible to use special reaction conditions. For example, potassium ferricyanide or the like is added to accelerate A. tumefaciens to convert sucrose to 3-ketosucrose. The main disadvantage of the whole cell application form is that side reactions may affect the yield and quality of the product. Choosing the right substrate or modifying the substrate may be solution to it.
With regard to the whole cell, bacteria are generally used only once, and some mycelia of mycelia can be used for several times. In order to overcome the difficulties in recovery, the current trend is to develop immobilized microorganisms, in particular to develop immobilized growing bacteria. The bacteria can be immobilized on polyacrylamide gels, collagen membranes or cellulose filters. For example, brevibacterium ammoniagenes embedded in a polyacrylamide gel can convert pantothenate to CoA through a five-step enzymatic reaction.
Enzyme solution
The enzyme solution has a wide range of applications and can be used in various processes such as substance conversion, product processing, process innovation, and waste disposal. This form mainly utilizes extracellular enzymes but is not limited to extracellular enzymes or microbially derived enzymes. The side reactions are few, and can be avoided by different levels of enzyme purification, thus ensuring the quality of the products. The main disadvantage of enzyme solutions is that they are difficult to be used repeatedly.
Immobilized enzyme
Immobilized enzymes are mainly used for the conversion of substances, and also in the process of product processing, innovative processes and disposal of wastes in some cases. This form also mainly utilizes extracellular enzymes. Since the immobilized enzyme can be sufficiently washed before the reaction, the reaction solution can be easily separated from the reaction liquid, so the product quality is better guaranteed.
The main advantage of the immobilized enzyme is that it can be used repeatedly. In particular, covalently coupled immobilized enzymes have a long lifetime. The available data indicates that immobilized enzymes can be used repeatedly for at least 10-15 times in batch applications, and in some cases up to 100 times; when applied in a continuous manner, generally equal time can be used. The number and time of repetitive use of immobilized bacteria are much less. In recent years, people have been working on the development of immobilized reactors, immobilizing enzymes on the same carrier or different carriers, or immobilizing enzymes directly on the cells for complex transformation and production. In theory, it may have the advantages of intact cells and immobilized enzymes, but there are still many problems in practical applications.
Related Services at Creative Enzymes:
Enzyme Stabilization and Formulation
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