DL-Methionine DL-Methionine

Structural formula

• Numbering system
• Physical property data
• Toxicological data
• Ecological data
• Molecular structure data
• Computing chemical data
• More
  • Properties and Stability
  • Storage method
  • Synthesis method
  • Purpose

Numbering system

CAS number:59-51-8

MDL number:MFCD00063096

EINECS number:200-432-1

RTECS number:PD0456000

BRN number:636185

PubChem number:24897336

Physical property data

1. Properties: White flaky crystals or powder.

2. Density (g/mL, 25/4℃): 1.340

3. Relative vapor density (g/mL, air=1): Undetermined

4. Melting point (ºC): 281℃ (decomposition)

5. Boiling point (ºC, normal pressure): Undetermined

6. Boiling point (ºC, 5.2kPa) : Undetermined

7. Refractive index: Undetermined

8. Flash point (ºC): Undetermined

9. Specific rotation (º): Undetermined

10. Autoignition point or ignition temperature (ºC): Undetermined

11. Vapor pressure (kPa, 25ºC): Undetermined

12 . Saturated vapor pressure (kPa, 60ºC): Undetermined

13. Heat of combustion (KJ/mol): Undetermined

14. Critical temperature (ºC): Undetermined

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15. Critical pressure (KPa): Undetermined

16. Log value of oil-water (octanol/water) partition coefficient: Undetermined

17. Explosion upper limit (%, V/V): Undetermined

18. Lower explosion limit (%, V/V): Undetermined

19. Solubility: soluble in water, dilute acid and Dilute alkali, very slightly soluble in 95% ethanol, insoluble in ether.

Toxicological data

1. Acute toxicity: rat oral LD: >5mg/kg; rat abdominal LD50: 2mg/kg; rat intravenous LD: >400mg/kg; mouse oral LC50: 4mg/kg; mouse abdominal LC50: 1500mg/kg; mouse intravenous LCLo: 300mg/kg2. Other multiple dose toxicity: rat oral TDLo: 36mg/kg/30D-C; rat oral TDLo: 21mg/kg/136D-C; rat oral TDLo: 39mg/kg/20D-C; Bird-turkey oral: 33600mg/kg/4W-C 3. Reproductive toxicity: Female rats oral TDLo: 40mg/kg, conception takes 1-20 days

Ecological data

None yet

Molecular structure data

5. Molecular property data:

1. Molar refractive index: 38.26

2. Molar refractive index: 38.26�� Volume (cm³/mol): 123.7

3. Isotonic specific volume (90.2K): 329.9

4. Surface tension (dyne/cm ): 50.5

5. Polarizability (10^-24cm³): 15.17

Compute chemical data

1. Reference value for hydrophobic parameter calculation (XlogP): None

2. Number of hydrogen bond donors: 2

3. Number of hydrogen bond acceptors: 4

4. Number of rotatable chemical bonds: 4

5. Number of tautomers: none

6. Topological molecule polar surface area 88.6

7. Number of heavy atoms: 9

8. Surface charge: 0

9. Complexity: 97

10. Number of isotope atoms: 0

11. Determine the number of atomic stereocenters: 0

12. Uncertain number of atomic stereocenters: 1

13. Determine the number of chemical bond stereocenters: 0

14. Number of uncertain chemical bond stereocenters: 0

15. Number of covalent bond units: 1

Properties and stability

1. Slightly sweet and has a special smell. Methionine is the only thioether-containing amino acid, divided into left-handed body (L-methionine, [63-68-3]) and right-handed body (D-methionine, [348-67-4]). Generally, the right-handed form of amino acids is invalid, with the exception of methionine. D-methionine can be converted into L-methionine in the body. It is precisely because these two kinds of methionine are biochemically effective that in the production of synthetic methionine, DL-methionine is directly used without separation. The commonly referred to as methionine generally refers to DL-methionine.

Storage method

Stored sealed and protected from light.

Synthesis method

1. Extraction method can be used to prepare methionine, but there are the following methods in industry: 1. Rhône-Planck process 2. Degussa DL-methionine process raw material consumption quota: acrolein 480kg/t, methylmercaptan 400kg/t, sodium cyanide 420kg/t.

2.It is synthesized from acrolein as raw material.

3.Use acrolein and methylmercaptan as raw materials to react to generate methylthiopropionaldehyde.

The product methylthiopropionaldehyde reacts with sodium cyanide to form hydantoin.

Hydantoin is hydrolyzed in the presence of sodium hydroxide to form sodium methionine.

Sodium methionine is neutralized with sulfuric acid to generate DL-methionine.

Purpose

1. The content of commercial methionine is ≥98.5%. It is one of the amino acids necessary for the growth of poultry and livestock animals. It is the “skeleton” amino acid for biosynthetic protein. It has a strong regulating effect on animal metabolism and is widely used in Medicine, food, feed and cosmetics and other fields. Among them, in medicine, it can be used as the main component of amino acid infusion and compound amino acid, and can also be used to synthesize medicinal vitamins. Its anti-fatty liver effect can be used to produce liver-protecting preparations; in food, it can be used for amino acid fortification of food and In the processing of food and health products, it can be used as a nutritional supplement. Because of its special smell, it is only used in fish cake products. In the feed industry, methionine is used in the largest amount and is used as a nutritional fortifier in feed to make up for the amino acid balance. Feed additives, among the varieties of amino acid nutritional feed additives, methionine accounts for 60%, lysine accounts for 30%, and other amino acids account for about 10%.

2.Used as a nutritional fortifier in feed, it can compensate for the amino acid balance. Lack of methionine in livestock and poultry can cause stunting, weight loss, weakened liver and kidney function, muscle atrophy, and coat deterioration. wait. Adding 1kg of methionine to the feed is equivalent to the nutritional value of 50kg of fish meal. The general addition amount is 0.05% ~ 0.2%.

3.Cosmetics are used as nutritional additives. Used as nutritional supplement in food. It can also be used as a fortified feed nutrient. In medicine, it is amino acid infusion, one of the main components of complex amino acids. It can also be used as a hepatoprotective preparation.