Amino acids

What are amino acids?

Amino acid is a kind of amphoteric organic compound containing basic amino group and acid carboxyl group, which is the basic constituent unit of biological function macromolecule protein.

Amino acids can be divided into protein amino acids and non-protein amino acids. Among them, protein amino acids, also known as standard amino acids, are directly involved in the synthesis of protein molecules. Amino acids can be divided into α-, β-, γ- and other amino acids according to the different positions of amino acids connected to the carbon chain, but the amino acids that constitute natural proteins in the biological world are α-amino acids, a total of 22 kinds, including 20 common amino acids and 2 uncommon amino acids. Non-protein amino acids, such as citrulline, ornithine and hydroxyproline, cannot be directly involved in protein synthesis and need to be modified to participate in protein synthesis.

Amino acids have different properties, such as isoelectric point and optical activity, because of their different structures and R groups. The detection of amino acids can also be screened and identified according to these different properties. At present, the detection methods developed include spectrophotometry, liquid chromatography, gas chromatography, infrared detection and other methods.

Amino acids are used in organisms to make antibody proteins, hemoglobin, enzyme proteins, hormone proteins, neurotransmitter substances and other raw materials, and can even be used to provide energy sources for organisms. It can be said that amino acids are the source of all life.

Nutritional classification

1)Essential amino acids: refers to the human body (or other vertebrates) can not autonomously synthesize or synthesis speed is far from meeting the needs of the body, must be supplied by external food, these amino acids are called essential amino acids. The essential amino acid requirement for adults is about 20% to 37% of the protein requirement. There are 8 kinds, their roles are:

Lysine: promotes brain development, is a component of liver and gallbladder, can promote fat metabolism, regulate pineal gland, mammary gland, luteum and ovary, and prevent cell degeneration;

Tryptophan: promotes the production of gastric and pancreatic juices;

Phenylalanine: involved in eliminating the loss of kidney and bladder function;

Methionine (methionine) : participates in the composition of hemoglobin, tissue and serum, has the function of promoting spleen, pancreas and lymph;

Threonine: has the function of transforming certain amino acids to achieve equilibrium;

Isoleucine: involved in regulation and metabolism of thymus, spleen and subcerebral glands;

Leucine: acts to balance isoleucine;

Valine: Acts on the corpus luteum, mammary gland and ovary.

2)Semi-essential Amino acids and Conditional Essential amino Acids:

Although the human body can synthesize but usually can not meet the normal needs of amino acids are also known as semi-essential amino acids or conditional essential amino acids, mainly arginine and histidine, in the growth period of children these two are essential amino acids. The amount of essential amino acids required by the human body decreases with age and is significantly lower in adults than in infants. Their functions are as follows:

Arginine: The compound preparation made of arginine and deoxycholic acid is an effective drug for treating syphilis, viral jaundice and other diseases.

Histidine: can be used as a biochemical reagent and pharmaceutical, can also be used to treat heart disease, anemia, rheumatoid arthritis and other drugs.

Non-essential amino acids: Amino acids that humans (or other vertebrates) can synthesize from simple precursors and do not need to obtain from food. Such as glycine, alanine and other amino acids.