Phenylalanine
Like other amino acids, phenylalanine is involved in the production of other amino acids. Especially in the liver, phenylalanine can be converted to tyrosine. For this purpose, however, it must be available in sufficient quantities. Phenylalanine is also needed for the production of messenger substances such as noradrenaline.
Threonine
Threonine, like other essential amino acids, can play an important role in enzyme regulation. It is also used in human medicine, for example, in the treatment of digestive disorders.
Arginine
In addition to the eight essential amino acids, there are twelve other, non-essential amino acids. One of these is arginine, which is needed especially during sports, stress and disease situations. Besides enzymes and messenger substances, arginine is also used to form body tissue such as skin, hair and muscles.
Cysteine
Cysteine is only present in small amounts in food, so a varied diet is required to maintain the cysteine balance. At least for adults, however, it is considered certain that the body can synthesize the entire cysteine requirement from the essential amino acid methionine, provided that the diet contains enough of it. In addition to its involvement in degradation and dissolution processes, it helps detoxify the body and also helps fight so-called free radicals in the body.
Histidine
A sufficient intake of histidine is particularly important in infancy, as otherwise growth retardation and functional disorders may occur. Histidine is also increasingly used during recovery from illness. The build-up of the blood pigment, the strengthening of the immune system and wound healing are the most important functions.
Tyrosine
Tyrosine is found in most proteins and is a basic substance for many other substances in the body. Tyrosine is a precursor of neurotransmitters, which are necessary for the transmission of nerve impulses. A deficiency over a long period of time can therefore have serious consequences.
Alanin
Alanine is mainly involved in the build-up of protein-containing substances and is mainly synthesized by the muscle cells. It also plays an important role in lowering the blood sugar level. A lack of alanine can in severe cases lead to muscle loss and be accompanied by attacks of weakness.
Asparagine
The best known source of asparagine is asparagus, in which this amino acid is found in large quantities. Together with asparagine acid, it has an important function in the human nervous system and acts as a transmitter. Both amino acids are also used in the uric acid cycle. The typical urine smell after a meal with asparagus is well known to everyone. Asparagine and asparagine acid also play a role here.
Glutamine and glutamic acid
Glutamine and glutamic acid have different tasks in the human metabolism. Especially after illnesses and operations a lack of glutamine is often apparent. Above all, glutamine plays an important role in the formation of protein compounds and is therefore found in many tissues (small intestine, immune system and mucous membrane cells).
A deficiency can lead to immunodeficiency and functional disorders of the digestive tract and thus impair the quality of life. Glutamic acid is mainly involved in the formation of proteins. In one study it could be shown that the higher the glutamic acid level of a patient, the worse the subjective feeling of sleep.
