Use and Manufacturing

1 DefinitionChEBI: The L-enantiomer of leucine.

2 Produe MethodLeucine is produced microbially by incubating an amino-acidproducingmicroorganism including but not exclusive to Pseudomonas,Escherichia, Bacillus, or Staphylococcus in the presence ofoxygen and a hydrocarbon. The nutrient medium should contain aninhibitory amount of a growth inhibitor that is a chemically similarderivative of leucine (e.g. methylallylglycine, a-hydrozinoisocaproicacid, or b-cyclopentanealanine) to inhibit the growth of theorganism except for at least one mutant that is resistant to theinhibitory effect. The resistant mutant is then isolated and grown inthe presence of oxygen and the hydrocarbon in the absence of theinhibitor. The mutant cells are then harvested and a nutrientmedium is formed that includes a hydrocarbon as the sole source ofcarbon. Finally, the harvested cells are incubated in the medium inthe presence of oxygen.

3 Purification MethodsLikely impurities are isoleucine, valine, and methionine. Crystallise L-leucine from water by adding 4 volumes of EtOH. It sublimes at 180-188o/0.3mm with 99.1% recovery, and unracemised [Gross & Gradsky J Am Chem Soc 77 1678 1955]. [Greenstein & Winitz The Chemistry of the Amino Acids J. Wiley, Vol 3 p 2075-2094 1961, Kameda et al. J Pharm Soc Jpn 78 763 1958, Beilstein 4 IV 2738.]

4 UsageAmino acid drugs. Used as amino acid infusion and comprehensive amino acid preparations. For the diagnosis and treatment of children with idiopathic high blood sugar and glucose metabolism disorders,bile liver disease associated with reduced secretion , anemia, poisoning, muscular dystrophy, poliomyelitis, neuritis and mental illness. Diabetes, cerebral vascular sclerosis and kidney disease associated with proteinuria and hematuria is contraindicated. Gastric and duodenal ulcer patients should not be served. The product is used as a nutritional supplement,an amino acid infusion preparation and a comprehensive amino acid preparation,a hypoglycemic agent, a plant growth promoter.The product can be used as a spice according to GB 2760-8 .