Glutathione (GSH) is a tripeptide compound formed by the condensation of glutamic acid, cysteine and glycine through peptide bonds, and is the most important low-molecular-weight thiol in mammalian cells to resist oxidant stress. Known as nature's antioxidant master, it is a colorless transparent and elongated granular crystal, soluble in water, dilute alcohol, liquid ammonia, dimethylformamide, insoluble in ethanol, ether, acetone. When it is solid, its properties are stable, and its aqueous solution is easily oxidized into oxidized glutathione in the air, which has the functions of anti-oxidation, scavenging free radicals, and delaying aging.