Glutathione is an active tripeptide formed by peptide bond condensation of glutamic acid, cysteine and glycine, which is widely distributed in animal liver, blood, yeast and wheat embryo, and also distributed in a small amount in various vegetables and other plant tissues. Glutathione has unique physiological functions and is called longevity factor and anti-aging factor. Japan began to develop and apply food in 1950s, and now it has been widely used in the field of food processing. The research on glutathione in China is still in its infancy.

There are four main production methods of glutathione: solvent extraction, chemical synthesis, microbial fermentation and enzyme synthesis. Among them, glutathione biosynthesis by microbial cells or enzymes has great development potential, and yeast fermentation is the main production method at present.

Glutathione molecules have specific γ -peptide bonds, which determine many important physiological functions in human body, such as the synthesis of protein and ribonucleic acid, the transport of oxygen and nutrients, the activity of endogenous enzymes, metabolism and cell protection, and participation in the tricarboxylic acid cycle and sugar metabolism. It has the functions of anti-oxidation, anti-fatigue, anti-aging, eliminating excessive free radicals in the body, detoxifying and protecting the liver, and preventing diabetes and cancer, so it has become the representative of human defense functional peptides. Glutathione can not only be used as a detoxification drug to treat corneal diseases, but also can be used as an additive for sports nutritious food and functional food.