Polypeptide is a compound formed by the bonding of α-amino acids with peptide bonds. It is also an intermediate product of protein hydrolysis. The compound formed by dehydration and condensation of two amino acid molecules is called dipeptide. By analogy, there are tripeptide, tetrapeptide, pentapeptide and so on. A compound usually formed by dehydration and condensation of 10 / 100 amino acid molecules is called a polypeptide.
Many active substances in the human body exist in the form of peptides. Peptides are involved in the fields of hormones, nerves, cell growth and reproduction. Their importance lies in regulating the physiological functions of various systems and cells in the body, activating the relevant enzymes in the body, promoting the permeability of the intermediate metabolic membrane, or by controlling the transcription of DNA or affecting the specific protein synthesis, and finally produce specific physiological effects. Peptides are important substances involved in a variety of cell functions in the human body. Peptides can synthesize cells and regulate the functional activities of cells. Peptides are used as neurotransmitters in the human body to convey information. Peptides can be used as a means of transportation in the human body, the human body eats a variety of nutrients and a variety of vitamins, biotin, calcium and beneficial trace elements to the human body cells, organs and tissues. Peptide is an important physiological regulator of human body, it can comprehensively regulate the physiological function of human body, enhance and give full play to the physiological activity of human body, it has important biological function. Peptides are too important to human cell activity, functional activity and life existence. However, due to various factors, modern people make the loss and loss of peptides in the human body, and the ability to synthesize peptides is greatly weakened. Therefore, the modern human body lacks peptides, so we must supplement synthetic peptides. Supplementary peptides are supplementary activities, supplementary peptides are supplementary activities, and supplementary peptides are complementary to life.
So how do polypeptide health foods be preserved? Polypeptide health food only needs to be placed in a cool and dry place.
For polypeptide reagents and polypeptide drugs, they need to be kept in a dryer. Freeze-dried peptides can be placed at room temperature before they are exposed to air. This will reduce the effect of humidity, and when freeze-drying is not possible, the best way to store it is to store it in a small working sample size. For polypeptide reagents containing Cys, Met or TrP, deoxidizing buffers are essential for their dissolution, because the polypeptide reagents are easily oxidized by air, and nitrogen or argon, which slowly flows through polypeptide reagents before sealing, also reduces oxidation. Polypeptide reagents containing Gln or Asn are also easy to degrade, and all of these peptides have a limited lifetime compared with those that do not contain these problematic glycosides.
Peptides have a wide range of solubility. The main problem of polypeptide insoluble is the formation of secondary structure. This occurs except for the teratopeptide, especially in peptides with multiple hydrophobic residues. Salt can promote the formation of secondary structure. We recommend dissolving peptides in aseptic distilled water or deionized water first. If it is necessary to increase the dissolution rate, ultrasonic treatment can be used. Dissolution is still a problem, adding a small amount of dilute acetic acid (10%) or ammonia will be easy to dissolve.
To preserve polypeptide reagents for a long time, it is best to freeze-dry, cold-dried powder can be stored at-20 ℃ or lower for a few years without degradation. The peptides in the solution are far from stable. Peptides are easily degraded by bacteria and dissolved in aseptic purified water.
The polypeptide solution containing Met,Cys or Tyr residues has limited life due to oxidation. In order to prevent repeated freeze-thaw damage, it is suggested that the excess peptides should be dissolved in the stool experiment, and the rest of the peptides should be preserved in solid form.