The structure of a-ketoglutaric acid is as follows:

α-ketoglutaric acid is also called α-glutaric acid; 2-oxoglutaric acid; α-carbonylpentanoic acid Diacid; chemical structural formula is: Molecular formula: C5H6O5; molecular weight 146.10, appearance is white or off-white crystalline powder.

The amino acid that can be directly converted into a-ketoglutarate is glutamic acid.

Glutamic acid, with a chemical formula of C5H9NO4 and a molecular weight of 147.13, is an acidic amino acid. The molecule contains two carboxyl groups, and its chemical name is α-aminoglutaric acid.

Glutamic acid was discovered by Lissouson in 1856. It is a colorless crystal with an umami taste, slightly soluble in water and soluble in hydrochloric acid solution, with an isoelectric point of 3.22. Glutamic acid is found in large amounts in cereal proteins and is also abundant in animal brains. Glutamic acid plays an important role in the protein metabolism process in organisms and participates in many important chemical reactions in animals, plants and microorganisms. MSG contains a small amount of glutamic acid.

In medicine, glutamate is mainly used to treat hepatic coma and is also used to improve the intellectual development of children. In the food industry, MSG is a commonly used food flavor enhancer, and its main component is sodium glutamate. In the past, the production of MSG was mainly carried out by hydrolysis of wheat gluten (gluten), but now microbial fermentation is used for large-scale production.

L-Glutamic acid is mainly used in the production of MSG, spices, and as salt substitutes, nutritional supplements, and biochemical reagents. L-glutamic acid itself can be used as a drug, participating in the metabolism of proteins and sugars in the brain, and promoting the oxidation process. This product combines with ammonia in the body to form non-toxic glutamine, which reduces blood ammonia and relieves the symptoms of hepatic coma.