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Glutamic acid

Glutamic acid is the major excitatory neurotransmitter in the central nervous system and it is widely accepted that anomaly of its control is involved in creation of pathological conditions of progressive encephalopathies such as disorder in memory, ischemic encephalopathy, amyotropic lateral sclerosis (ALS), Parkinson's disease, and Huntingon's chorea. Gamma aminobutyric acid (GABA) and glutamic acid are two major neurotransmitters involved in the regulation of brain neuronal activity. GABA is the major inhibitory neurotransmitter and L-glutamic acid is an excitatory transmitter. An imbalance in the concentration of these neurotransmitters can lead to convulsive states. The enzyme glutamic acid decarboxylase (GAD) catalyses the conversion of L-glutamic acid to the inhibitory neurotransmitter gamma-amino butyric acid (GABA). In addition to having various functions for neurotransmission, glutamic acid participates in many other important brain functions such as life and death, and differentiation and propagation of neurocytes, development of neurocytes and gliacytes, and plastic change in neurotransmission efficiency of matured or developed brains. L-glutamic acid is produced mainly by fermentation utilizing so-called L-glutamic acid-producing coryneform bacteria belonging to the genus Brevibacterium, Corynebacterium or Microbacterium or mutant strains thereof. Glutamic acid which is one of alpha-amino acids is widely distributed in proteins. It is generally known that a tasty component of tomatoes used as a seasoning and also a tasty component of fermentation products of soybeans are glutamic acid. Glutamic acid is synthesized in the first step of nitrogen metabolism in higher plants. glutamine and asparagine formed from glutamic acid are distributed to tissues through phloems and used for the synthesis of other amino acids and proteins. L-glutamic acid in the form of its monosodium salt is an important flavor-enhancing material for foods and is widely used in the preparation of processed food. There is an increasing demand for the amino acid, glutamic acid in the form of its sodium salt; monosodium glutamate (MSG). This demand is due to the use of MSG as a flavour enhancer in food applications in amongst others meat, sauces and soya-based products.

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