An amino acid, L-Citrulline can be used in the treatment of asthenia and as an essential intermediate in the biosynthesis of nitric oxide.
Purification Methods
Likely impurities are arginine and ornithine. Crystallise S-citrulline from water by adding 5 volumes of EtOH. Also crystallise it from water by addition of MeOH. [Ellenbogen J Am Chem Soc 74 5198 1952, Greenstein & Winitz The Chemistry of the Amino Acids J. Wiley, Vol 3 pp 2491-2494 1961, Beilstein 4 IV 2647.]