Proteins in the serum are critical to maintaining the pH balance in the body; it is largely the charged amino acids that are involved in the buffering properties of proteins. Aspartic acid is alanine with one of the β hydrogen replaced by a carboxylic acid group. The pKa of the β carboxyl group of aspartic acid in a polypeptide is about 4.0
Note that aspartic acid has an α-keto homologue, oxaloacetate, just as pyruvate is the α-keto homologue of alanine. Aspartic acid and oxaloacetate are interconvertible by a simple transamination reaction, just as alanine and pyruvate are interconvertible.
Aspartic acid is oxidized in the TCA cycle through the formation of oxaloacetic acid, which is ultimately converted into glucose and glycogen. By the process of transamination aspartic acid may take part in the synthesis of glutamic acid.
Aspartic acid moves the coenzyme nicotinamide adenine dinucleotide (NADH) molecules from the main body of the cell to its mitochondria, where it is used to generate adenosine triphosphate (ATP), the fuel that powers all cellular activity. In short, the more NADH a cell has, the more chemical fuel it produces, and the more energy you have to get through your day. (Some studies have shown that aspartic acid actually increases both stamina and endurance levels in athletes.) In addition, this amino acid helps transport minerals needed to form healthy RNA and DNA to the cells, and strengthens the immune system by promoting increased production of immunoglobulins and antibodies (immune system proteins).
Sources of aspartic acid
It is found in dairy, beef, poultry, sprouting seeds.
Benefits of aspartic acid
It is of great importance in the metabolism during construction of other amino acids and biochemicals in the citric acid cycle. Among the biochemicals that are synthesized from aspartic acid are asparagine, arginine, lysine, methionine, threonine, isoleucine, and several nucleotides.
It is needed for stamina, brain and neural health and assists the liver by removing excess ammonia and other toxins from the bloodstream. It is also very important in the functioning of RNA, DNA, as well as the production of immunoglobulin and antibody synthesis.
It also helps in the expulsion of harmful ammonia from the circulatory system. When ammonia enters the circulatory system it acts as a highly toxic substance, which can be harmful to the central nervous system and cause neural and brain disorders.
Through the synthesis of adenine, aspartic acid functions in the synthesis of NAD and NADP.
Deficiency of aspartic acid
Deficiency of aspartic acid may cause fatigue and depression.
Aspartic acid deficiency decreases cellular energy and may likely be a factor in chronic fatigue.
Daily requirement for aspartic acid is listed in the recommended daily allowance (RDA), but be aware that this dosage is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the toxicity level must be kept in mind.
Other important facts
Aspartic acid keeps mind sharp by increasing concentrations of NADH in the brain, which is thought to boost the production of neurotransmitters and chemicals needed for normal mental functioning. It also removes excess toxins from the cells, particularly ammonia, which is very damaging to the brain and nervous system as well as the liver.