L-Alanine is considered as a supplementary amino acid. The presence of carbon atom in its composition leads to the formation of L alanine, which is organic in nature. The best sources of L-alanine would be fish, beef, pork and poultry. The various protein sources which are animal based would consist of a good amount of l-alanine. The alanine levels increases with the contraction of muscles in the body. L- alanine is used by the body to build proteins. It also helps in the transfer of nitrogen from the tissues in our body. It helps to draw blood sugar and hence acts as a good energy resource producer. This would be best suited for those who want a reduction in extra body fat.

L-Arginine is a very important amino acid that is required by the body for a number of functions. One of the main functions of L-Arginine is its ability to rid the body of ammonia, which is a waste product. It is also used in the manufacture of nitric oxide, which helps to relax the blood vessels, thereby increasing the flow of blood and reducing the chances of a heart attack. It is advised that supplements of L-Arginine should not be administered following a heart attack for fear that it could possibly aggravate cardiac shock. L-Arginine is being used in treating people with erectile dysfunction, as it relaxes the blood vessels surrounding the penis. It is also used in treating migraine and blood pressure.

L-Aspartic Acid is a natural amino acid and is mainly used as medicine. This can be employed as chemic and biologic reagent, organic synthesized intermediate and culture medium. This is useful as medicine for heart disease, accelerant for liver function and also is a significant component for transfusion of amino acid. L-Aspartic acid is a crystalline powder that comes odorless and has acid taste. This is lightly soluble in water but is perfectly soluble in acid. However, it is insoluble in ether or ethanol. L-Aspartic acid is mixed in nutritional supplements and cool drinks. This is also useful as medicine or fatigue refresher. This can be employed as biochemical reagent and as an important raw material for sweetener as well as for pharmaceuticals. L-Aspartic acid is an important ingredient in the pharmaceutical industry especially in the manufacturing processes. L-Aspartic acid is employed in the form of salt for mineral supplementation.

L-Cysteine is one of the many naturally occurring amino acids. It is further termed as a protein amino acid. Promoting the stomach lining health is one of the main functions of l-cysteine. It also helps in correction of situations where the essential nutrients from food sources are not being absorbed properly. Generally, most people do not need supplements for obtaining l-cysteine amino acid. It is can easily be found in vegetable, meats and dairy products. Although, l-cysteine is also available in the form of cysteine, which is found in plenty of protein enriched foods. Cysteine is one of those amino acids which are not destroyed by cooking. On the contrary, research shows that cooking of food rich in cysteine may help you absorb them better.

L-Glutamic Acid- In the proteinogenic group of twenty amino acids, the group that is deemed the building blocks of proteins, L-Glutamic Acid is one of the more commonly known ones. The reason for this fame are the carboxylate anions and salts of the glutamic acid, the glutamates. Glutamic acid is present in many fermented or aged food sources, such as cheese and soy sauce, but also in yeast extracts. The sodium salt of glutamic acid, monosodium glutamate, is a very popular and widely used food additive. Glutamate is an extremely important molecule in cellular metabolism. Glutamate is also one of the most commonly occurring excitatory neurotransmitters. Glutamate has been also identified as a precursor to GABA inhibitor. Glutamic acid is deemed responsible for one of the five basic tastes, the human taste sense commonly called umami.

L-Glycine- Glycine is an organic compound and one of the 20 amino acids deemed as building blocks for proteins. This proteinogenic amino acid is not only the smallest but also the only amino acid of the group that is not chiral, which means there is no enantiomer of glycine. With the prominent exception of collagen, which thirty five percent are glycine, most proteins contain only small amounts of it. As a solid, glycine is sweet tasting, crystalline and has no color. Despite being non-essential, because it can be biosynthesized from the amino acid serine, glycine has several important physiological functions, besides being a precursor to proteins. It is a biosynthetic intermediate of purines and the D-Aminolevulinic acid and it is an inhibitory neurotransmitter found in the central nervous system.

L-Histidine is an essential amino acid that produces histamine, which aides with allergy systems.

L-Isoleucine is an essential alpha-amino acid that is considered both, a ketogenic and a glucogenic amino acid. Since that L-Isoleucine is an essential amino acid, it cannot be synthesized by the body, therefore it needs to be ingested. The primary source of L-Isoleucine is as a component of proteins. It has become a prominent component of nutritional supplements, mostly with the body building and similar athletic communities, where it is believed that L-Isoleucine has the capability to increase endurance, but also to repair muscle tissue. It has been observed that L-Isoleucine ingestion allows power athletes to recover easier from very tough trainings and exhausting activities. This branched chain amino acid is one of the three main BCAA in the body, the other ones being valine and leucine.

L-Leucine with the food additive E number code E641 is classified as a flavor enhancer. Leucine is actually an essential alpha-amino acid and a vital part of so called “buffer” proteins, such as ferritin and astacin. You can find leucine in foods such as whole wheat bread products, nuts and brown rice. As a supplement, researchers have found that leucine slows the degradation of muscles and muscle tissues through an inflated synthesis of muscle proteins. In the human body, leucine can be found in the liver, but most prominently in the muscle and adipose tissues, where it is utilized in production of sterols. In body building circles L-Leucine as a dietary supplement is very popular for all these properties, but also for the preservation of muscle glycogen, nitrogen balance maintenance and more.

L-Methionine- One of the most significant amino acids there is for the breaking down of fats. It is water-soluble and is known for deactivating free radicals. Recognized as being a leading antioxidant.

L-Phenylalanine gained notoriety with the aspartame controversy where extensive internet bombardment against the artificial sweetener prompted a thorough cleaning by The Coca Cola Company and other interest groups. Now it seems that aspartame has more benefits to health than aspirin. L-Phenylalanine is an essential alpha amino acid that is deemed analgesic and antidepressant. It is hydrophobic and nonpolar, one of only twenty common amino acids that are used to produce protein as coded by the DNA. L-Phenylalanine can also convert into L-Tyrosine, which can then become L-DOPA, going forth to become norepinephrine, dopamine or epinephrine. Phenylalanine is very often found in foods, protein rich foods like meat, milk and milk products, poultry and fish, but also as already mentioned in the artificial sweetener aspartame.

L-Proline is a proteinogenic alpha amino acid, one of only twenty amino acids that are DNA encoded for the forming of protein. It is not deemed essential because humans are able to synthesize it from the amino acid L-Glutamate. This unique member of the twenty protein building block amino acids is the only one of the group that is distinct as belonging to the secondary alpha amino group. L-Proline plays a role in the synthesis of collagen. Collagen is undeniably the most common protein in mammals, being found in skin, tendons, joints, ligaments, vasculature and bones. It is deemed good for the health of joints, when taken as a supplement. Low protein diets, vegetarian and vegan diets as well as malnutrition lead to diminished L-Proline levels.

L-Serine- Serine is an organic compound and a proteinogenic amino acid that is considered a building block for the creation of proteins. This member of the hydroxyl group and a polar amino acid is not essential and therefore it is not necessary to ingest it by means of diet. L-Serine can be synthesized from metabolites such as glycine. L-Serine plays a role in the biosynthesis of pyrimidines and purines, furthermore it is a precursor to many metabolites like sphingolipids and to amino acids like cysteine and glycine. It is also involved in catalytic functions of several enzymes. L-Serine can be transformed into D-Serine by the serine racemase, which functions as a neuronal signal and NMDA receptor activator in the brain, a vital glutamate receptor responsible for memory functions and synaptic plasticity.

L-Threonine- 2-amino-3-hydroxybutanoic acid, or L-Threonine, an enantiomer of Threonine, which is an essential amino acid, needs to be ingested by way of diet, predominantly through Threonine containing proteins. There are two ways how Threonine can be metabolized, namely conversion into pyruvate by utilizing Threonine dehydrogenase, whereby an intermediate can thiolyze with CoA, producing acetyl-CoA and glycine; and the second possibility, where Threonine is changed into alpha-ketobutyrate, utilizing serine dehydratase, towards becoming succinyl-CoA. Succinyl CoA is a CAC intermediate, which means that it is a part of the citric acid cycle. The citric acid cycle is a vital part of the metabolic pathway which is securing the conversion of carbohydrates, proteins and fats towards usable energy. Foods containing Threonine are meat, poultry and fish and related products, cottage cheese, sesame seeds and lentils.

L-Tryptophan- Tryptophan is an essential amino acid as well as within the group of only twenty standard amino acids that are required by the human diet. It is one of the building blocks required for protein biosynthesis. It is also viewed as a precursor to serotonin and thereby also melatonin, niacin and also auxin. Interestingly enough, lactose intolerance and fructose malabsorption have the side effect that tryptophan is only improperly absorbed in the intestines which leads to diminished levels of it in the system. Dietary sources of tryptophan are plentiful, it can be found in red meat, poultry, fish, milk, milk products, peanuts, mangoes, dates, chocolate and oats, among others. As a dietary supplement tryptophan has found applications as a safe sleeping aid and also as a calming agent.

L-Tyrosine is a protein non-essential building block Although non-essential it is important for the structure of body proteins. It has a direct effect on neurotransmitters.

L-Valine is an amino acid with stimulant activities. It not only helps in tissue repair but also promotes muscle growth. It is one of the three branched amino acids that are formulated for providing support to the human body for normal functioning. Derived from animal and vegetable protein, L-Valine is not only involved in the synthesis of protein and metabolism of glucose but it also regulates the immune system. L-Valine is also effective in maintaining the exercise recovery time and the balance of nitrogen in the body. Since the human body doesn’t produce this amino acid naturally, you need to acquire it through dietary supplements and food items. When taking L-Valine supplements, you must follow strict directions from the physician. Even though it doesn’t have any side effects, it helps to consult the physician before its usage.