Bioengineering is a high technology of modern science and technology, and it is one of the most promising disciplines today. Enzyme engineering is an important part of bioengineering. As a biocatalyst, enzymes are widely used in more than 20 fields such as food, brewing, starch sugar, tanning, printing, medicine, and petrochemicals.
Bioengineering is a high technology of modern science and technology, and it is one of the most promising disciplines today. Enzyme engineering is an important part of bioengineering. As a biocatalyst, enzymes are widely used in more than 20 fields such as food, brewing, starch sugar, tanning, textile, printing, medicine, and petrochemicals. It can improve product quality, improve product technology, reduce labor intensity, save raw materials and energy, protect the environment, and produce huge economic and social benefits.
Globally, 55% of the total enzyme preparation is hydrolase, which is mainly used in baked goods, wine making, starch processing, alcohol and textile industries. 35% are proteases, mainly used in detergent, tanning and dairy industries; the rest are pharmaceutical enzyme preparations, reagent-grade enzyme preparations and tool enzymes.
Enzyme engineering technology is the technology that uses the catalytic function of enzymes and cells or organelles to produce products required by humans, including the development and production of enzymes, the immobilization of enzymes and cells or organelles, the modification and modification of enzyme molecules, and biosensors.
Enzyme production is a process of optimization and combination of various biotechnology. It is divided into three types: biological extraction method, biosynthesis method and chemical synthesis method. Among them, the biological extraction method is the earliest method and is still in use today. It refers to the extraction of enzymes from animals, plants, organs, cells or microbial cells using various extraction, separation and purification techniques. Biosynthesis is the main method of enzyme production since the 1960s. It refers to the technical process of obtaining the enzymes needed by people using the life activities of microbial cells, plant cells or animal cells. The chemical synthesis method, because of its high cost, can only synthesize enzymes whose chemical structure has been clarified, so it is difficult to carry out industrial production and is still in the laboratory research stage.
Enzyme purification belongs to a post-treatment process, including a crude process and a refining process. Concentrating and refining superenzyme solution is an important part of producing high-quality enzyme preparations. The purification method is generally established based on the size, shape, charge properties, solubility, specific binding site and other properties of the enzyme. To obtain pure enzymes, various methods are generally used in combination. The most commonly used purification method is precipitation based on solubility characteristics. Ion exchange chromatography based on charge polarity, isoelectric focusing electrophoresis, etc. Centrifugation, dialysis, ultrafiltration, etc. according to size or weight. Affinity chromatography and covalent chromatography according to the affinity site.
The chemical nature of the enzyme is protein, and its biggest disadvantage is instability. It is prone to denaturation of the enzyme protein to acid, alkali, heat and organic solutions, thereby reducing or losing activity. In addition, the enzyme often reacts in the solution, which will remain in the solution system after the reaction and is not easy to recover, causing troubles in the separation and purification of the final product. In addition, the enzyme reaction can only be carried out in batches, which is difficult to be continuous and automated. This greatly hinders the development and application of enzyme engineering. In order to overcome the above disadvantages, the free enzyme needs to be immobilized before application.
The enzyme immobilization technology is to immobilize the enzyme extracted from the organism on the carrier by artificial methods. This is the core of enzyme engineering, which brings the enzyme engineering to a new level. Since the first use of solid-phase enzyme technology in the world in 1969, it has more than 40 years of history. Since the movement of the immobilized enzyme is restricted by chemical or physical methods, it can be recovered from the reaction medium, so in principle the enzyme can be reused in batch operations or continuous operations.
The immobilized enzyme has the following properties: the stability of the enzyme is improved; the optimum pH value is changed; the enzyme activity and catalytic substrate are changed; the optimum temperature is increased, and the sensitivity to inhibitors and proteases is reduced; After the reaction is completed, it can be recovered by a simple method and the enzyme activity remains unchanged. At the same time, because the enzyme is not released into the product, it is convenient for the separation and purification of the product; the possibility of implementing batch or continuous operation models can be carried out in industrialized, continuous, and automated production.
The Naming and Characteristics of Restriction Endonucleases
Restriction enzymes, also known as restriction endonucleases, are enzymes that cut double-stranded DNA. Its cutting method is to cut the bond between the carbohydrate molecule and the phosphoric acid, and then create a nick on each of the two DNA strands without damaging the nucleotides and bases.
Introduction to Classification and Application of Cellulase
The optimum pH of cellulase is generally 4.5 to 6.5, which acts on cellulose and products derived from cellulose. Microbial cellulase is of great significance in converting insoluble cellulose into glucose and destroying cell walls in fruit and vegetable juice to improve the yield of juice.
Which Enzyme Preparations Are Often Used in Fruit and Vegetable Processing?
The so-called fruit and vegetable processing means to maximize the nutrient content of the fruit and vegetable through various processing methods, improve the edible value, and make the color, aroma and taste of the processed product more perfect.
