Peptide compounds are ubiquitous in nature. They are chemical substances produced by connecting α - carbohydrates with peptide chains. In addition, they are also intermediate substances of protein hydrolysis. It has many functions, such as hormone regulation, hormone regulation, enzyme regulation, antiviral treatment, anti-oxidation, lowering blood lipid, lowering blood lipid and so on. As a precursor of drugs, it is safe to use, and the digestion and absorption rate of the body is faster than that of carbohydrates, so it has been paid more and more attention. At present, the scientific research, development and design of microbial active peptides have become a hot network in pharmaceutical engineering projects.
However, the basic peptide composition is low and complex, especially the physical and chemical properties of the residue are very similar to the overall target peptide, so it is difficult to separate and purify. Trypsin Hydrolysis is common, but in addition to the active polypeptides, there are also some UN hydrolyzed proteins, carbohydrates, trypsin and so on. In order to obtain the target specific active peptides, it is necessary to carry out deep-seated separation and purification. At present, the key ways to isolate and purify active polypeptides are ultrafiltration membrane, protein denaturation, gel electrophoresis, ion exchange chromatography, chromatographic analysis and electrophoretic principle. They are all created on the basis of carbohydrate and active polypeptide, active polypeptide and active polypeptide, active polypeptide and protein. According to different requirements, they must be applied in several ways Fusion application, the following lists several kinds of common peptide drug separation and purification methods:
(1) . ultrafiltration membrane.
Ultrafiltration membrane is a kind of sample separated by the pore size and relative molecular weight of Dow reverse osmosis membrane. Ultrafiltration membrane is the most common way to separate and purify active polypeptide in membrane separation equipment. When solving the problem of active polypeptide sample, two technological processes must be connected together, namely enzymatic hydrolysis and ultrafiltration membrane separation. According to the characteristics of the solution sample, the suitable membrane raw materials can be selected, and then the relative molecular weight of the commodity can be manipulated. The ultrafiltration membrane processing technology consumes a lot of water in the whole process of operation, so the extraction in the middle and later stage will consume time. If the pretreatment method of raw material liquid is not correct, the membrane pore will be blocked and the service life of membrane will be harmed, and the cost will be high.
(2) Salt effect:
In aqueous solution, the high concentration of neutral salt can make macromolecules gather together to produce sedimentation, which is the whole process of protein denaturation. The characteristic groups of NH2, - Oh, - COOH and other proteins and peptides are water absorbing functional groups, which can fuse with water to form coagulation layer, and then cooperate with protein molecular structure to produce water absorbent colloidal solution, which can reduce the force between protein molecules and improve the solubility of proteins and active polypeptides. Adding a lot of neutral salts to the hydrolysate, the neutral salts can make a lot of water flow out, destroy the membrane structure engineering, expose the hydrophobicity, neutralize the positive charge, and destroy the water absorbing colloidal solution, so as to make the protein and active polypeptide aggregate into sedimentation and obtain the target active polypeptide. Although the protein denaturation process is easy to operate and low in cost, it is difficult to avoid enhancing the composition of active peptide salt and harming its taste.
(All Rights Reserved)