L-Serine is an amino acid that is synthesized by the human body and is used in the biosynthesis of proteins. It plays a vital role in the production of enzymes, muscle tissue, and various neurotransmitters. L-Serine is also involved in the synthesis of various amino acids, including glycine, cysteine, and tryptophan. 56-45-1 L-Serine is commonly used as a supplement in sports nutrition products and as a food additive. It is also used in the production of pharmaceuticals and cosmetics.