Use and Manufacturing

1 DefinitionChEBI: The L-enantiomer of methionine.

2 General DescriptionMinute hexagonal plates from dilute alcohol.

3 Produe MethodNumerous methods have been described for manufacture ofmethionine, including hydrolysis of methionine amide )and 5-(bmethylmercaptoethyl)-hydantoin.

4 Purification MethodsCrystallise L-methionine from aqueous EtOH. Also purify it by dissolving ~0.5g of amino acid in ~10mL of hot H2O, filtering, adjusting the pH to 5.8 with 5N HCl, collecting the solid after addition of ~20mL of EtOH. It is recrystallised by dissolving in H2O and adding EtOH. It sublimes at 197-208o/0.3mm with 99.8% recovery and unracemised [Gross & Gradsky J Am Chem Soc 77 1678 1955]. [Milne & Peng J Am Chem Soc 79 647 1957, Greenstein & Winitz The Chemistry of the Amino Acids J. Wiley, Vol 3 pp 2125-2152 1961, Beilstein 4 IV 3189.]

5 UsageAmino acid drugs, nutritional supplements. Used for fatty liver and cirrhosis. Also widely used as feed additives to improve feed quality, improve the utilization of the native protein and promote animal growth. Such as DL-methionine can increase egg production of chickens, pigs make weight gain, more milk cows and so on. Adverse reaction: hepatic coma hanged. Nutritional supplements. One of the essential amino acids of the human body. Because the price is higher than DL-methionine and the results are equal, so commonly used DL-methionine. For biochemical studies and nutritional supplements, and as adjunctive treatment for pneumonia, liver cirrhosis and fatty liver.