Basic Info.
Product Description
L-Cysteine
Product Name | L-Cysteine |
Category | Amino acids |
Analysis | HPLC |
Storage | Keep in cool and dry place, well-closed, away from moisture or direct sunlight. |
L-Cysteine is one of the 20 natural amino acids and, besides methionine,the only one which contains sulfur. It is a thiol-containing non-essential amino acid that is oxidized to form Cystine. It is a non-essential sulfur-containing amino acid in humans, related to cystine, Cysteine is important for protein synthesis, detoxification, and diverse metabolic functions. Found in beta-keratin, the main protein in nails, skin, and hair, Cysteine is important in collagen production, as well as skin elasticity and texture. Also required in the manufacture of amino acid taurine, Cysteine is a component of the antioxidant glutathione, and plays a role in the metabolism of essential biochemicals such as coenzyme A, heparin, and biotin.
L-cysteine hydrochloride is used in the baking industry as dough conditioner. Specially, it breaks the disulfide bonds of gluten, which lowers the viscosity of the dough. It is then easier to work with and increases the elasticity of the dough, helping it to rise during baking.
L-cysteine is available through many dietary sources, primarily animal protein. Eggs and dairy products also contain significant levels of l-cysteine. Vegetable sources of l-cysteine include broccoli, Brussels sprouts, garlic, granola, sprouted lentils, oats, onions and peppers. The commercial extraction of l-cysteine typically uses human hair, due to its high concentration of this amino acid. Other commercial sources include hog hair and poultry feathers. L-cysteine may also be synthesized in a process that involves fermentation by a variety of E. coli.
Testing Item | Standard | Result |
Appearance | White crystals or crystalline powder | conforms |
Specific rotation[a]D20 | + 8.3°~ +9.5° | +8.72° |
State of solution (Transmittance) | ≥95.0% | 98.5% |
Loss on drying | ≤0.50% | 0.18% |
Residue on ignition | ≤0.10% | 0.07% |
Heavy metals(Pb) | ≤10PPM | <10PPM |
Chloride (Cl) | 600---1000ppm | 800ppm |
A rsenic (As2O3) | ≤1PPM | conforms |
Iron (Fe) | ≤10PPM | <10PPM |
A mmonium (NH4) | ≤0.02% | <0.02% |
Sulfate (SO4) | ≤0.030% | ≤0.030% |
Other amino acids | Chromatographically | Qualified |
PH value | 4.5 ~ 5.5 | 5.0 |
Assay | 98.0%~101.0% | 99.4% |