A substitute for glutamine in mammalian cell culture media; stable to heat-sterilization.L-Alanyl-L-glutamine is used as a component in pharmaceuticals, cosmetics and food products. It is a stable Gln dipeptide, which protects mice against the jejunal crypt depletion in the setting of dietary protein and fat deficiency. It provides nutritional requirements, improves intestinal health and enhances the immune system. It is also involved in various clinical studies such as cancer treatment, radiation and chemotherapy. It finds application in biotechnology as a component for mammalian cell culture medium. It improves pancreatic beta-cell function, maintaining the mitochondrial metabolism and stimulus-secretion coupling essential for insulin release.