L-Cysteine manufacturers and suppliers

Properties

Melting point:: 240 °C (dec.) (lit.)

alpha: 8.75 º (c=12, 2N HCl)

Boiling point:: 293.9±35.0 °C(Predicted)

Density: 1.197 (estimate)

refractive index: 8.8 ° (C=8, 1mol/L HCl)

FEMA: 3263 | L-CYSTEINE

storage temp.: Store below +30°C.

solubility: H₂O: 25 mg/mL

form: Solid

pka: 1.92(at 25℃)

color: White

PH: 4.5-5.5 (100g/l, H2O, 20℃)

Odor: sulfury

Odor Type: sulfurous

optical activity: Optical rotation: +8° to +9° (c = 5, 1 N HCl, 20°C).

Water Solubility: 280 g/L (25 ºC)

Sensitive: Air Sensitive

λmax: λ: 260 nm Amax: 1.5
λ: 280 nm Amax: 0.2

JECFA Number: 1419

Merck: 14,2781

BRN: 1721408

Stability:: Stability Stable, but may be air sensitive. Incompatible with oxidizing agents, bases.

LogP: -2.49

Safety Information

Symbol(GHS): GHS07

Signal word: Warning

Hazard statements: H302

Precautionary statements: P264-P270-P301+P312a-P330-P501a

Hazard Codes: Xn,Xi

Risk Statements: 22-36/37/38-20/21/22

Safety Statements: 36-37/39-26-24/25

WGK Germany: 3

RTECS: HA1600000

F: 10-23

Autoignition Temperature: 420 °C

TSCA: Yes

HS Code: 29309012

Toxicity: LD50 orally in Rabbit: 1890 mg/kg

Use

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. L-Cysteine is a non-essential amino acid that can be synthesized by the human body under normal physiological conditions if a sufficient quantity of methionine is available. L-Cysteine is commonly use d as a precursor in the food and pharmaceutical industries. L-Cysteine is used as a processing aid for baking, as an additive in cigarettes, as well as in the preparation of meat flavours.L-Cysteine is a non-essential amino acid that can be synthesized by the human body under normal physiological conditions if a sufficient quantity of methionine is available. L-Cysteine is commonly use d as a precursor in the food and pharmaceutical industries. L-Cysteine is used as a processing aid for baking, as an additive in cigarettes, as well as in the preparation of meat flavours.Dietary sourcesAlthough classified as a non - essential amino acid, in rare cases, cysteine may be essential for infants, the elderly, and individuals with certain metabolic disease or who suffer from malabsorption syndromes. Cysteine can usually be synthesized by the human body under normal physiological conditions if a sufficient quantity of methionine is available. Cysteine is catabolized in the gastrointestinal tract and blood plasma . In contrast, cystine travels safely through the GI tract and blood plasma and is promptly reduced to the two cysteine molecules upon cell entry. Cysteine is found in most high-protein foods, including : Animal sources: pork, sausage meat, chicken, turkey, duck, luncheon meat, eggs, milk, whey protein, ricotta, cottage cheese, yogurt Plant sources: red peppers, garlic, onions, broccoli, brussels sprout, oats, granola, wheat germ, sprouted lentils. Like other amino acids, cysteine has an amphoteric character.Industrial sourcesThe majority of L-cysteine is obtained industrially by hydrolysis of poultry feathers or human hair. Synthetically produced L-cysteine, compliant with Jewish Kosher and Muslim Halal rules, is also available, albeit at a higher price . The synthetic route involves fermentation utilizing a mutant of E. coli. Degussa introduced a route from substituted thiazolines. Following this technology, L-cysteine is produced by the hydrolysis of racemic 2-amino-Δ22-thiazoline-4- carboxylic acid using Pseudomonas thiazolinophilum.BiosynthesisIn animals, biosynthesis begins with the amino acid serine. The sulfur is derived from methionine, which is converted to homocysteine through the intermediate S- adenosylmethionine. Cystathionine betasynthase then combines homocysteine and serine to form the asymmetrical thioether cystathionine. The enzyme cystathionine gamma-lyase converts the cystathionine into cysteine and alphaketobutyrate. In plants and bacteria, cysteine biosynthesis again starts from serine, which is converted to O-acetylserine by the enzyme serine transacetylase. The enzyme O-acetylserine (thiol)-lyase, using sulfide sources, converts this ester into cysteine, releasing acetate.L-cysteine (chemical name, 2-amino-3-mercaptopropionic acid or mercapto alanine) is a mercapto-containing aliphatic neutral amino acid. It is colorless crystal with isoelectric point of 5.07, PK1 = 1.71, pK2 = 8.33, and pK3 = 10.78. It is Soluble in water, ethanol, acetic acid and ammonia, while not soluble in benzene, carbon tetrachloride, ethyl acetate, carbon disulfide, ether and acetone. L-cysteine is an essential component of the protein and can be synthesized from serine or methionine in animals. L-cysteine comes to decompose while heated to 240 ° C, and can be quickly oxidized by air to form cystine in neutral or slightly alkaline solution. The acid solution of L-cysteine can be stored for several days, and stored better under the protection of nitrogen. The aqueous solution of levorotatory L-cysteine changes into dark blue after adding ferric chloride. It can be produced by the degradation of cystine, and also can be obtained by the hydrochloric acid hydrolysis, copper oxide treatment and then hydrogen sulfide decomposition of human hair and other silkworm. L-cysteine can be used for anti-radiation and the treatment of radiation sickness, as well as for hepatitis, liver poisoning, radiopharmaceutical poisoning, acrylonitrile and antimony poisoning and allergic diseases in medicine. It can also be applied for the biochemical and nutritional research. Pyruvate and mercaptoethanamine are its general catabolites. It is involved in the synthesis of glutathione, taurine and so on. The disulfide bridge in the polypeptide chain is also formed by dehydrogenation and condensation of two molecules of cysteine.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. L-cysteine, also known as cysteine, is a non-essential amino acid of the human body. Amino acids are protein components and protein is the material basis of life. Ranging from human to microorganism, all consist of protein. Protein is composed of peptides, and peptide chain is composed of amino acids. Different proteins are composed of peptide chains in different order and length. Genes related to heredity are in fact amino acid chains in different orders. L-cysteine is closely related to cysteine, and two molecules of cysteine can form a cysteine. Cysteine is relatively unstable and easy to become cysteine. Cystine can also re-generate cysteine. These two both are sulfur-containing amino acids, which affect the formation of skin and can be used for detoxification. L-cysteine is present in keratin, which is the major protein that makes up nails, toenails, skin and hair. L-cysteine can help the production of collagen, and can maintain the skin's elasticity and texture. It is also related to the protein of digestive enzymes, and cysteine can supply –SH group to many important enzymes, such as succinate dehydrogenase and lactate dehydrogenase. L-cysteine is mainly used in the field of cosmetics, medicine and food. In cosmetics, it can be used for the preparation of perm essence, sunscreen, hair-restoring perfume and other nourishing hair essence. In the field of medicine, it is mainly used for the preparation of methyl cysteine, ethyl cysteine, acetyl cysteine, cysteine methyl ester, cysteine ethyl ester as well as comprehensive amino acid preparations and other drugs. Cysteine can be used as protective agent for radiation damage. In food, L-cysteine can be used as bread fermentation aid (ripening agent), stabilizer of milk powder and fruit juice antioxidants and nutrition of pet food and so on. The above information is edited by andy of Chemicalbook.L-cysteine is an important precursor for antioxidants such as glutathione – a product metabolized in the liver. Glutathione is essential for the breakdown of toxins in the body, such as alcohol. L-cysteine is also the precursor for other important antioxidants that help ward off cancer by decreasing the incidence of cell mutation. Cancer is caused by the replication of genetic mistakes (mutations) that go unnoticed by the cell’s recognition system. In healthy cells, mutations are caught and denatured before replication continues. If mutations are not caught, then the on/off mechanisms that monitor cell formation may be disrupted allowing uncontrolled proliferation of cells into tumors. A healthy cell rich in amino acids such as L-cysteine, has a better chance of sensing and discarding such mutations. L-cysteine benefits can also include improved heart and circulatory system health. Inflammation plays a key role in heart health. The inflammation response causes a cascade of events to bring fluids, proteins and cells to damaged tissues. Some of these substances carried in an inflammatory response are sticky and can get stuck on the walls of arteries. The presence of L-cysteine has been found to directly regulate this adhesion of sticky substances to the walls of arteries and therefore has a positive effect on the health of our hearts. figure 1: L-Cysteine 500mg, 100 Tablets