L-cysteine, a common amino acid in organisms. Mainly used in medicine, cosmetics, biochemical research, etc. Used in bread to promote the formation of gluten, promote fermentation, mold release, and prevent aging. Used in natural juices to prevent vitamin C oxidation and prevent the juice from turning brown. This product has detoxification effect and can be used for acrylonitrile poisoning and aromatic acidosis. The product also has the effect of preventing radiation damage to the human body. It is also a drug for the treatment of bronchitis, especially as a phlegm medicine (mostly used in the form of acetyl L-cysteine methyl ester.Cosmetics are mainly used for beauty water, Perm lotion, sun-proof skin cream, etc.