body. Because of the characteristics of GA and its derivatives, they are widely used in medical therapies, nutritional supplements, feed additives, and plant growth supplements. In its molecular structure, GA has two carboxyl groups and one amino group. It is an amphoteric substance possessing both acidic and basic properties and it finds many uses in cosmetic and cleansing products, foods, and in other chemical manufacturing processes.

Molecular structure of GA (Molecular formula of GA: C5H9O4N)

Application of GA

Medical and nutrition supplementary applications:
There is abundant GA in human blood and organs. Other than serving as a raw material in protein syntheses, it is also involved in the transmittance of central nervous system. Gln is responsible for nitrogen transportation about human body and serves as the main source of energy to several kinds of cells. It is due to the fact that GA is directly involved in the metabolic Krebs cycle (TCA cycle) that GA plays an indispensable role in human body metabolism.

Therefore, GA has been employed in treatments of disorders of nervous system such as epilepsy, added to dietary supplements for post-operation patients, and wholesome intravenous feeding nutritive solutions, which has also been used extensively lately for minimizing post-surgery infections and strengthening patient's immunity such as the activation of T-cells. There has been tremendous progress in the physiological studies of various peptides and proteins synthesized with GA as one of their main components. Those peptide and proteins are used not only in dietary supplements, but also, such as in the case of glutathion, made into part of synthetic antibiotics and other pharmaceuticals for human health cares.

Feed applications:
GA and Gln are just as important to animals physiologically as they are to human beings. For instance, chicken would stop growing if there is severe deficiency in GA alone. GA is quite often blended into commercial chicken feed in the form of MSG.

Food and fragrant essence applications:
The amino group in GA can easily undergo Maillard reaction with reducing sugars possessing a carbonyl group, and thereby to form fragrant compounds. With various sugars, it can be made into all kinds of different fragrant ingredients that are eatable and light in color and thus suitable for adding into food without spoiling the appearance of food products. It is therefore widely used in food processing industry.

Applications to culture medium for microorganism cultivation:
GA happens to be one of the main components in the cell wall of Gram-positive bacteria. It is also one of the more essential amino acids for other microorganisms to grow on. In most cases, it is often necessary to add GA into culture media to effect normal growth.

Agricultural applications:
GA is one of the major amino acids in plant proteins and Gln plays a role of the major nitrogen storage for plants. That is why GA is often one of the more prominent ingredients in many plant growth supplements. Besides, since GA is vital in the nitrogen metabolism in plants, it can be somewhat modified purposely to cut down on its capability to form Gln by combining with ammonia, and the accumulation of ammonia inside the plant can result in premature death of the organism. Therefore, this modification can be utilized as a measure to kill weeds.

Chemical product applications:

• Surfactants and buffers:
  GA is an amphoteric substance that contains both acidic and basic functional groups and thus a natural buffer by itself. It is hydrophilic by nature and can combine with hydrophobic fatty acids easily to form molecules with both water-soluble and water repelling portions that can be used as surfactants. There are many applications of GA derivatives as surfactants, especially due to its lack of harmful effects to skin and their general smooth appearance, it is very much favored by cosmetic, moist containing and hair shampooing product manufacturers. The amino acid when used with other organic acids can also be made into precursors of superconductors such as yttrium, barium and copper salts of organic acids.
• Gelatinizers:
  The surfactants made by combining GA and various fatty acids can further react with compounds with ammonium group to result in some emulsifiers, which is very useful especially in recovering process of spilt oil in cases of petroleum pollution accidents.
• Hardeners:
  Some derivatives of GA can be made into hardeners such as the one for epoxy resins by enhancing the adhesive force of the resin.
• Chelating agents:
  GA has two carboxylic groups, which can form chelates with many metal cations. Such chelating reaction is useful in the removal of heavy-metal contaminants in the wastewater treatment processes.

Applications of GA in non-food product fields

• Reagents employed in research and analytical standards
  Mainly in research work of biochemistry, bioassays, and protein syntheses.
  Medical therapies and pharmaceuticals.
  Nutritive supplements through enteral or parenteral routes, i.v. solutions, and drugs for metabolic disorders, hypertension, neuroregulating cases, and ophthalmic solutions.
  Raw material for chemical synthetic process
  Synthetic drugs, agricultural chemicals, surfactants, and other chemicals.
  Ingredients for cosmetic products.
  Ultraviolet light block, moisturizer, nutritive additives in shampoos and the like.

• GA crystals, crystalline MSG, GA-HCl crystals or solution, and other salt forms of GA

• Feed additive
  It will lift the appetite of piglets, enhance their consumption of food and increase the growth rate of the animal.
• Plant growth supplements