L-Threonine

L-Threonine is an essential amino acid with specific physical properties that influence its behavior in biological systems and industrial applications. Below is a detailed breakdown of its physical characteristics: 1. Molecular Structure and Formula IUPAC Name: (2S,3R)-2-Amino-3-hydroxybutanoic acid Chemical Formula: C49NO3 Molecular Weight: 119.12 g/mol Stereochemistry: L-Threonine has two chiral centers (at carbon 2 and 3), giving it four stereoisomers. The biologically active form is (2S,3R), which has a hydroxyl group on the β-carbon (C3) and an amino group on the α-carbon (C2). 2. Physical State and Appearance Solid Form: White to off-white crystalline powder Crystal Structure: Monoclinic crystals (under standard conditions) Odor and Taste: Odorless, with a slightly sweet taste 3. Solubility and Physical Constants Water Solubility: Highly soluble in water (approx. 20.5 g/100 mL at 25°C). Its polarity (from the amino, carboxyl, and hydroxyl groups) enables strong hydrogen bonding with water. Solubility in Organic Solvents: Poorly soluble in non-polar solvents (e.g., ether, chloroform) but slightly soluble in polar organic solvents like ethanol (approx. 0.5 g/100 mL at 25°C). Melting Point: 255–257°C (with decomposition). The high melting point reflects strong intermolecular interactions (hydrogen bonds and ionic interactions between amino and carboxyl groups). pH of Aqueous Solution: Neutral aqueous solutions of L-threonine have a pH around 5.9–6.1, but the pH can vary with concentration. 4. Optical Activity Specific Rotation: [α]₂₀ᴰ = -28.5° to -31.5° (in 1 M HCl solution). This indicates that L-threonine rotates plane-polarized light to the left (levorotatory) under standard conditions. Optical Purity: Natural L-threonine is optically pure, while synthetic forms may require resolution to obtain the L-isomer. 5. Ionization and Acid-Base Properties (1)pKa Values: α-Amino group (-NH3^+): pKa ≈ 9.10 α-Carboxyl group (-COOH): pKa ≈ 2.09 β-Hydroxyl group: Not ionizable under physiological conditions, but the hydroxyl can form hydrogen bonds. (2)Isoelectric Point (pI): Calculated as (pKa1 + pKa2)/2 = (2.09 + 9.10)/2 ≈ 5.60. At this pH, L-threonine exists as a zwitterion (NH3^+-CH(CHOHCH3)-COO^- ) with minimal net charge.
Other supplier products
|
|
L-Cysteine hydrochloride monohydrate Wholesale Price |
Handling and Storage Practices1. Sealing After UseImmediate Re-Sealing: After opening, remove the required amount quickly and re-seal the container... |
|
|
DL-Alanine Powder Price |
The original commercial packaging of DL-Alanine is designed for its stability:
Unopened products: Keep in the original sealed bag/bucket (usually... |
|
|
L-proline 147-85-3 |
Basic informationStructural characteristics: The molecular structure of L-proline is rather unique. Its α -amino group is an imine, and the h... |
|
|
Sucralose powder Food additive |
Sucralose, as a new generation of high-sweetness sweetener, has demonstrated comprehensive and outstanding application advantages in the fields of ... |
|
|
Fish collagen peptides Manufacturer |
Fish collagen peptides are a type of protein derivative obtained from fish. Here are the main aspects about them:
Source: They are mainly extract... |
All supplier products
Same products
|
|
Sucralose powder Food additive |
Seller: Shanghai Yifu Food Ingredients Co., Ltd |
Sucralose, as a new generation of high-sweetness sweetener, has demonstrated comprehensive and ou... |
|
|
Sucralose Purchase price |
Seller: Shanghai Yifu Food Ingredients Co., Ltd |
Sucralose, as a high-sweetness, calorie-free, and highly stable artificial sweetener, enjoys wide... |
|
|
Sucralose Partners, long-termCooperation |
Seller: Shanghai Yifu Food Ingredients Co., Ltd |
Sucralose is currently a widely used high-potency sweetener globally. Its safety has been verifie... |
|
|
Sucralose Marke quotation |
Seller: Shanghai Yifu Food Ingredients Co., Ltd |
Sucralose is a high-sweetness agent obtained by replacing the hydroxyl groups at positions 4, 1',... |
|
|
Sucralose Supply price |
Seller: Shanghai Yifu Food Ingredients Co., Ltd |
Sucralose is a trichloro derivative of sucrose (4,1',6'-trichloro-4,1',6'-dideoxy-galactosucrose)... |