Glycyl-L-glutamine (also known as Gly-Gln) is a dipeptide composed of the amino acids glycine and L-glutamine. It serves as a stable, highly soluble alternative to free L-glutamine, which is notoriously unstable in aqueous solutions and degrades rapidly during heat sterilization or long-term storage. Due to its enhanced stability, Glycyl-L-glutamine is widely used as a glutamine supplement in cell culture media, particularly in biopharmaceutical manufacturing and academic research, to support cell growth and metabolism. It is also found in certain clinical nutrition products and sports supplements, as it helps maintain plasma glutamine levels, supports immune function, and aids in muscle recovery after intense exercise. Once absorbed, the dipeptide is readily hydrolyzed to release free glutamine, providing a controlled and efficient delivery of this conditionally essential amino acid.
