Name | L(-)-Carnitine |
Synonyms | CAR-OH Vitamin BT L-Carnitine CARNIKING(R) CARNIFEED(R) CARNITINE, L- L(-)-Carnitine (D)L-Carnitine Levocarnitinep L-(-)-Carnitine L-Carnitine Base ME3-GAMMA-ABU(BETA-HYDROXY)-OH 3-Hydroxy-4-(trimethylammonio)butanoate (R)-3-HYDROXY-4-(TRIMETHYLAMMONIO)BUTYRATE (R)-BETA-HYDROXY-GAMMA-(TRIMETHYLAMMONIO)BUTYRATE L-Carnitine Tartrate,L-carnitine,Vitamin BT,L-ca greatrnitine,L-ctheirrnitine |
CAS | 541-15-1 |
EINECS | 208-768-0 |
InChI | InChI=1/C7H15NO3/c1-8(2,3)5-6(9)4-7(10)11/h6,9H,4-5H2,1-3H3/t6-/m1/s1 |
InChIKey | PHIQHXFUZVPYII-ZCFIWIBFSA-N |
Molecular Formula | C7H15NO3 |
Molar Mass | 161.2 |
Density | 0.64 g/cm3 |
Melting Point | 197-212°C(lit.) |
Boling Point | 287.5°C (rough estimate) |
Specific Rotation(α) | -31 º (c=10, H2O) |
Water Solubility | 2500 g/L (20 ºC) |
Solubility | Easily soluble in water and hot ethanol, absorbing moisture in the air, slightly soluble in cold ethanol, insoluble in acetone, ether |
Appearance | White crystal |
Color | White |
Merck | 14,1849 |
BRN | 4292315 |
pKa | 3.80(at 25℃) |
PH | 6.5-8.5 (50g/l, H2O) |
Storage Condition | Store below +30°C. |
Stability | Hygroscopic |
Sensitive | Easily absorbing moisture |
Refractive Index | -32 ° (C=1, H2O) |
MDL | MFCD00038747 |
Physical and Chemical Properties | Melting point 208-212°C specific optical rotation -31 ° (c = 10, H2O) water-soluble 2500g/L (20°C) |
Use | For drugs, nutrition and health products, functional beverages, feed additives |
Hazard Symbols | Xi - Irritant |
Risk Codes | 36/37/38 - Irritating to eyes, respiratory system and skin. |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36 - Wear suitable protective clothing. S37/39 - Wear suitable gloves and eye/face protection |
WGK Germany | 3 |
RTECS | BP2980000 |
FLUKA BRAND F CODES | 3-10 |
HS Code | 29239000 |
Hazard Note | Irritant |
Toxicity | LD50 orally in Rabbit: > 5000 mg/kg |
Raw Materials | Epichlorohydrin Epichlorohydrin |
Reference Show more | 1. Liu Shengjing, Guo Boda, Guo Jun, etc. Protective effect of Qilin pill on the reproductive system of rats with asthenospermia and its regulation mechanism [J]. Chinese Journal of Andrology, 2019, v.33(06):24-28. 2. Guo Boda, Zeng Yin, Guo Jun, etc. Protective Mechanism of huanshao capsule on reproductive function damage in rats with ornidazole-induced asthenospermia [J]. Chinese Journal of Andrology, Volume 26, 202005, pages 446-451, MEDLINE ISTIC PKU CSCD, 2020. 3. Shu Jin, Wang Haiya, Jin Li. Effect of matrix metalloproteinase-3 on the viability of myocardial fibrosis cells in rats [J]. Geriatrics and healthcare, 2020,26(03):476-479 492. 4. Li Zhao Min, Wang Hao Fei, Yang Lin, Gu Xue Dong, Zhu Yahui. Enzymatic determination of L-carnitine in muscle of different animals from Linzhi [J]. Plateau Agriculture, 2020,4(06):601-607. 5. [IF = 13.273] Congfei Yao et al."Efficient separation of phenol from model oils using environmentally benign quaternary ammonium-based zwitterions via forming deep eutectic solvents."Chem Eng J. 2017 Oct;326:620 6. [IF=2.775] Congfei Yao et al."Ternary phase behavior of phenol toluene zwitterionic alkaloids for separating phenols from oil mixtures via forming deep eutectic solvents."Fluid Phase Equilibr. 2017 Sep;448:116 7. [IF=5.396] Xiangnan Zhang et al."Chlorogenic acid inhibits trimethylamine-N-oxide formation and remodels intestinal microbiota to alleviate liver dysfunction in high L-carnitine feeding mice."Food Funct. 2021 Nov;12(21):10500-10511 8. [IF=5.396] Qiu Wu et al."A faster and simpler UPLC-MS/MS method for the simultaneous determination of trimethylamine N-oxide, trimethylamine and dimethylamine in different types of biological samples."Food Funct. 2019 Oct;10(10):6484-6491 9. [IF=5.279] Xiangnan Zhang et al."Decaisnea insignis Seed Oil Inhibits Trimethylamine-N-oxide Formation and Remodels Intestinal Microbiota to Alleviate Liver Dysfunction in l-Carnitine Feeding Mice."J Agr Food Chem. 2019;67(47):13082-13092 10. [IF=4.466] Yao Tan et al."Multiomics Integrative Analysis for Discovering the Potential Mechanism of Dioscin against Hyperuricemia Mice."J Proteome Res. 2021;20(1):645-660 11. [IF=2.1] Jin Shu et al."Matrix metalloproteinase 3 regulates angiotensin II‑induced myocardial fibrosis cell viability, migration and apoptosis."Mol Med Rep. 2021 Feb;23(2):1-1 |
White Crystal or transparent powder, melting point 200 ° C (decomposition). Soluble in water, alkali, methanol and ethanol, insoluble in acetone and acetate, insoluble in chloroform. Hygroscopic.
from epichlorohydrin and trimethylamine into quaternary ammonium salt reaction of 3 monochloro-2-hydroxypropyl trimethylamine chloride, and then by cyanation into 3-cyano -2-hydroxypropyl trimethylamine chloride, carnitine hydrochloride was obtained by hydrolysis with concentrated hydrochloric acid. Alternatively, ethyl y bromoacetoacetate is used as a raw material, which is first reduced to ethyl y bromoβ-hydroxybutyrate with sodium tetrahydroborate, and then formed with trimethylamine to form a quaternary ammonium salt, I .e., ethyl bromotrimethylammonium-p-hydroxybutyrate, and finally hydrolyzed with hydrochloric acid. It can also be extracted directly from beef and cow's milk containing L-carnitine.
for fortified soy-based baby foods to promote fat absorption and utilization. It is also a high-quality active substance for weight loss. China's provisions can be used for biscuits, bread and milk drinks, the use of 600 ~ 3000mg/kg/in solid beverages, drinks and capsules in the use of 250 ~ 600mg/kg; in the milk powder in the amount of 300 ~ mg/kg; In the baby food in the amount of 70~90mg/kg (L-carnitine, lg tartrate equivalent to 0. 68G L-carnitine).
update date: | 2022/11/12 10:05:38 |
LogP | -5.48 at 20℃ |
Introduction | Carnitine is a kind of B vitamins, and its structure is like amino acids, so some people classify it as amino acids. Its main function is to help transport long-chain fatty acids to provide energy. This prevents fat from accumulating in the heart, liver and skeletal muscle. Synthetic carnitine has three forms: left-handed body, right-handed body and racemate. L-carnitine has a better effect. L-carnitine is a compound with a variety of physiological active functions. Its main function is to promote fatty acid β-oxidation. It can also regulate the ratio of mitochondrial acyl groups and affect energy metabolism. L-carnitine can participate in the transportation of branched chain amino acid metabolites, thus promoting the normal metabolism of branched chain amino acids. In addition, L-carnitine plays a role in the elimination and utilization of ketone bodies. It can be used as a biological antioxidant to scavenge free radicals, maintain the stability of the membrane, improve the immunity of animals and the ability to resist diseases and stress. Recent studies have shown that L-carnitine and acetyl-L-carnitine play an important role in energy metabolism in sperm mitochondria, which can eliminate ROS and protect sperm membrane function. Oral administration of L-carnitine and acetyl-L-carnitine can increase the total number of forward motile sperm and total motile sperm for patients with oligospermia and asthenospermia, and increase the clinical pregnancy rate of the woman, which is safe and effective. Clinical experimental studies at home and abroad have shown that carnitine treatment of male infertility is a new breakthrough in the field of male infertility drug treatment in recent years, and its in-depth research is very necessary to further clarify its mechanism of action and clarify its indications. |
Chemical properties and metabolism | L-carnitine, also known as L-carnitine, has a chemical structure similar to choline and is similar to amino acids, but it is not an amino acid and cannot participate in protein biosynthesis. Since L-carnitine can be synthesized by humans and most animals to meet their physiological needs, it is not a real vitamin, but a vitamin-like substance. L-carnitine is very soluble in water, and the carnitine ingested from the diet can be completely absorbed by the human body. It is known that the site of absorption of L-carnitine in the body is the small intestine, but the exact process and site of absorption of carnitine (free or esterified) through the intestinal mucosa are still unclear. In addition to exogenous L-carnitine ingested from food, humans can also synthesize endogenous carnitine by themselves. The liver and kidney are the main organs for the biosynthesis of carnitine in the body. Starting from lysine, they pass ε-trimethyl-β hydroxylysine, and generate γ-butyl betaine under the action of aldolase and aldehyde oxidase., And then converted into L-carnitine by hydroxylase. In addition to lysine, the biosynthesis of L-carnitine in the body also requires methionine and substances such as vitamin C, niacin and vitamin B6. |
Discovery history | L-carnitine (L-Carnitine) was formerly known as vitamin BT. It was first discovered in meat sauce by Russian chemist Gulewitsch and Krimberg in 1905. Tomita and Senju determined its chemical structure in 1927. Twenty years later, in 1947, Fraenkel discovered that the growth of insects such as yellow mealworms required a factor in yeast, which was called vitamin BT at that time. Then in 1952, Carter and others at Illinois State University confirmed that vitamin BT was L-carnitine. Figure 1 is the structural formula of L-carnitine |
food source | carnitine is a kind of vitamin, l-carnitine is one of them, widely exists in animals, plants and microorganisms, and is one of the basic components of microorganisms, animals and plants. There are two main sources for the human body: ① Intake from the diet. Among them, meat and dairy products are the most abundant, and the content of vegetables and cereals is extremely small or even no. The adult body contains about 20g carnitine, and the body is mainly supplemented by red meat. Generally, the carnitine content in plant foods is low, and the carnitine content in animal foods is high. In animal foods, the content of meat is the highest (such as the content of L-carnitine in goat meat is 2100mg/kg), followed by viscera, and very few eggs. Most animals have the ability to synthesize L-carnitine. Mammals contain a lot of L-carnitine in skeletal muscle and heart muscle. ② endogenous synthesis. With the participation of lysine (mainly L-lysine), methionine, vitamin C, nicotine, vitamin B6 and reduced iron, L-carnitine is synthesized from the liver, kidney, brain and other major parts of the human body through a 5-step reaction. |
physiological function and function | recent studies have shown that L-carnitine also plays a certain role in promoting ketone body utilization and nitrogen metabolism. 1. Promote the transport and oxidation of fatty acids The β-oxidation of fatty acids is carried out in the mitochondria of liver and other tissue cells. It is known that neither free fatty acids nor fatty acyl-CoA can penetrate the inner mitochondrial membrane, while fatty acyl carnitine (Acylcarnitine) can quickly pass through this membrane, thus confirming that L-carnitine is a fatty acid in the form of fatty acids. A carrier transferred from outside the mitochondrial membrane to the membrane. The detailed mechanism of this transport is still unclear, but it is certain that carnitine acyl-CoA transferase (Carnitine acyl-CoA transferase) is the key enzyme in this process. Some people believe that L-carnitine can also participate in the transport and excretion of other acyl groups, so it can prevent the body from metabolic poisoning caused by the accumulation of acyl groups or is conducive to the normal metabolism of some branched chain amino acids. 2. Accelerate sperm maturation and improve motility L-carnitine is an energy substance for sperm maturation, which has the function of improving sperm number and motility. A survey of 30 adult men showed that the number and motility of sperm were proportional to the supply of L-carnitine in the diet within a certain range, and the content of L-carnitine in sperm was also positively correlated with the content of L-carnitine in the diet. 3. Improve the body's tolerance Watanabe and others have found that L-carnitine can improve the tolerance of patients with diseases in practice, such as practice time, maximum oxygen absorption, lactic acid threshold, oxygen absorption threshold and other indicators. After the body is supplemented with L-carnitine, there will be varying degrees of improvement; oral L-carnitine can also increase muscle tolerance during maximum oxygen absorption by 80%, and shorten the recovery period after strenuous exercise, reduce the tension and fatigue caused by exercise. Santulli et al. found in 1986 that L-carnitine can increase the growth rate of hatched cultured perch and reduce the content of cholesterol and triglyceride in fish tissues. Germany reported that after 3 weeks of intake of L-carnitine, the body fat content of athletes decreased significantly, and the proportion of protein increased but the weight was not affected. |
can l-carnitine lose weight | l-carnitine is not a weight loss drug, its main function is to burn fat, and weight loss is not the same thing. If you want to use L-carnitine to lose weight, in addition to burning fat, a lot of exercise is still the key to weight loss, carnitine only plays an auxiliary role. If the amount of exercise is not large, such as just dieting to lose weight, taking L-carnitine has no effect on weight loss. |
mechanism of action | l-carnitine is a kind of vitamin that promotes the conversion of fat into energy and has no toxic and side effects on human body. The most prominent physiological function of L-carnitine is to act as a carrier for fatty acid transportation. In the form of acetyl L-carnitine, the medium and long-chain fatty acids are transferred from the cell mitochondrial membrane to the membrane, which is oxidized in the mitochondrial matrix to generate energy. For example, it is like a forklift, which can scoop up fat and burn it into a fuel furnace to provide energy. It acts as a "porter" from fat to mitochondria. It is internationally recognized as a safe and non-toxic fat reduction nutrient fortifier. It is recommended to eat 1-5 grams of L-carnitine internationally. It is especially suitable for people to cooperate with aerobic exercise to reduce fat, and the effect is obvious. L-carnitine is produced in the liver and kidneys of the human body and stored in muscle, semen, brain and heart. |
application and prospect | l-carnitine, as a new nutritional fortifier, has been widely used in functional foods, especially as an additive for infant formula food, athlete food and weight-loss bodybuilding food. L-carnitine as a commodity is mainly its hydrochloride, tartrate and magnesium citrate. 1. Application in infant formula L-carnitine plays an important role in the metabolism of infants using fat as an energy source. Due to the weak biosynthetic ability of L-carnitine in infants, it cannot meet its normal metabolism. Therefore, exogenous L-carnitine must be ingested to ensure that the body fat is in the best oxidation state and provide enough energy to maintain the normal body temperature of infants. In addition, L-carnitine can also promote the growth and development of infants and young children and improve their metabolic balance. Therefore, it is necessary to fortify L-carnitine in infant food, especially soybean-based infant formula food, because the content of L-carnitine in soybean is very low. The limit of L-carnitine for infant formula food in China is 70~90mg/kg. At present, L-carnitine fortified infant formula milk powder is on the market in China. 2. Application in athletes' food According to Decombaz J. et al., the concentration of free carnitine in human muscle tissue will drop by 20% after strenuous exercise, and it is believed that carnitine supplementation can improve the body's fatigue, because L-carnitine can promote fat oxidation in the body, provide sufficient energy for the body, and is conducive to the improvement of exercise durability and explosive power. If the combination of 28 alcohol and L-carnitine is used, it will have a multiplier effect on enhancing physical strength, which is manifested as the relaxation of the whole body muscles, the increase of explosive power and endurance, the increase of basal metabolic rate, and the improvement of the nutritional status of the myocardial layer. A common method is to add L-carnitine to athletes' drinks for fortification. 3. application in weight loss and bodybuilding food as early as the 1970s, there were patent reports of DL-carnitine used to prevent and treat obesity. Subsequently, DL-carnitine was replaced by L-carnitine as it was found to have a negative effect. Practice has proved that L-carnitine fortified foods have a good effect on fat metabolism disorders caused by carnitine deficiency in the body, and can prevent obesity and fatty liver caused by the accumulation of lipids in muscle fibers and liver. disease. Sang Tian believes that the obese type with insufficient exercise has a lot of fat in the body and the biosynthetic ability of carnitine is low. By ingesting L-carnitine, excess fat in the body can be effectively converted into energy and released, which plays a role in preventing and treating obesity. Therefore, lipid-lowering foods with L-carnitine as the main ingredient are quite popular in the European market. |
content analysis | FCC method accurately weighed about 1.0g of sample and dissolved in water in a 250ml flask. When weighing, try to avoid moisture absorption. Titration with 1.0mol/L hydrochloric acid to the end of potentiometric titration. At the same time, a blank titration is performed and necessary corrections are made. 1.0mol/L hydrochloric acid per ml is equivalent to C7 H15NO3 161.2mg. Take about 0.1g of this product by GB method, weigh it accurately, add 20ml of glacial acetic acid to dissolve, add a drop of crystal violet indicator solution, titrate with perchloric acid solution (0.1mol/L) until the solution shows pure blue, and correct the titration result with blank test. Content (%)={(V1-V2)? C1 × 0.162/M1 (1-X2)}× 100 Volume of Perchloric Acid Standard Solution Consumed by V1 Titration Test Solution in Formula, ml;V2 -- Volume of Perchloric Acid Standard Solution Consumed by Titration of Blank Solution, ml; Concentration of C1-Perchloric Acid Standard Solution, mol/L; M1-mass of sample, g; x2-the percentage of moisture in the sample,%;0.1612-the quality of L-carnitine in grams equivalent to 1.00ml of perchloric acid standard titration solution [c(HClO4)= 1.00mol/L]. The arithmetic mean of the parallel measurement results is taken as the measurement results, and the relative difference of the parallel measurement results is not more than 0.3%. |
toxicity | Adl 20 mg/kg. LD502272 ~ 2444 mg/kg (rabbit, via mouth). |
usage limit | GB 2760-1996: chewable tablets, drinks, capsules, 250~600mg/tablets, branches and pills; Milk powder, 300~400 g/kg; Juice (flavor) beverage, milk beverage, 600~3000 mg/kg. |
use | L-carnitine is a newly approved animal nutrition fortifier in China. It is mainly used to strengthen protein-based additives, which can promote the absorption and utilization of fat. Type D and DL have no nutritional value. The usage amount is 70-90mg/kg. (in terms of L-carnitine, 1g tartrate is equivalent to 0. 68gL-carnitine). L-carnitine is a newly approved food fortifier in China. It is mainly used to strengthen soybean-based baby food and promote fat absorption and utilization. D-type and DL-type have no nutritional value. According to regulations of our country, it can be used for biscuits, drinks and milk drinks, with a usage of 600~3000 mg/kg; The usage amount in solid drinks, drinks and capsules is 250~600 mg/kg; The usage amount in milk powder is 300~400 mg/kg; The usage amount in infant formula is 70~90 mg/kg (calculated as L-carnitine, 1g tartrate is equivalent to 0.68gL-carnitine). used for drugs, nutrition and health products, functional drinks, feed additives, etc. appetite enhancer. It can promote the fatty acid oxidation of mitochondria and achieve other biochemical functions. These functions include acetyl buffering and maintaining sufficient concentration of coenzyme A in mitochondria in the absence of oxygen, stimulating the circulation of tricarboxylic acids and stimulating the output of ATP from mitochondria under sustained muscle exercise. For healthy growth of animals. |
production method | extraction method L-carnitine naturally exists in various meat and milk, so it can be directly extracted from beef and milk containing L-carnitine. Literature reports that 0.6g of crystalline carnitine can be extracted from 450g of beef extract and 100g of lactose powder containing 2% L-carnitine can be extracted from 56kg of milk. However, the extraction method is costly and economically unreasonable. Studies on microbial fermentation method show that L-carnitine also exists in many microorganisms. L-carnitine can be accumulated by liquid submerged culture or solid fermentation of microorganisms such as yeast, Aspergillus, Penicillium, Rhizopus and so on. However, due to the complexity of the screening of strains, the current fermentation level is still relatively low. It is reported that 2% DL-carnitine is used as raw material and fermented at 25 ℃ for 44h to accumulate L-carnitine 0.4%. Synthetic method There were patent reports of DL-carnitine synthesis abroad in 1953, and industrial production in the 2060s. In 1982, there was also the production and application of stomach medicine in China. Directly starting from DL-carnitine, using camphoric acid, N-acetyl-D-glutamic acid or ethylbenzoyl-L-(+) tartaric acid as the splitting agent, chemical resolution was carried out to obtain L-carnitine. However, carnitine racemization is difficult and cannot be recycled, and industrial production still needs breakthrough progress. Enzymatic transformation is the most studied and most promising method. The DL-carnitine obtained by chemical synthesis can be acetylated to make amide or nitrile, etc., and then selective hydrolysis and resolution can be carried out by enzymes derived from microorganisms. For example, the amidase of Pseudomonas and other microorganisms can selectively hydrolyze DL-carnitine amide or carnitine nitrile with an optical purity of more than 99%. In addition, L-carnitine can also be prepared by enzymatic conversion of β-dehydrocarnitine, enzymatic hydrolysis of trans-croton betaine and enzymatic hydroxylation of γ-butyl betaine. At present, only Switzerland, Italy, Japan and other countries produce internationally. The Institute of Microbiology in Jiangsu Province of China is also carrying out research on enzymatic transformation. (1) extraction method. It is naturally found in various meat and milk, so it can be directly extracted from beef and milk containing L-carnitine. Literature reports that 0.6g of crystalline carnitine can be extracted from 450g of beef extract and 100g of lactose powder containing 2% L-carnitine can be extracted from 56kg of milk. However, the extraction method is more costly and less economically reasonable. (2) Microbial fermentation. Studies have shown that L-carnitine also exists in many microorganisms. L-carnitine can be accumulated by liquid submerged culture or solid fermentation of microorganisms such as yeast, Aspergillus, Penicillium, and Rhizopus. However, due to the complexity of the screening of strains, the current fermentation level is still relatively low. It is reported that 2% DL-carnitine is used as raw material and fermented at 25 ℃ for 44h to accumulate L-carnitine 0.4%. (3) Synthetic method. There were patent reports of DL-carnitine synthesis in foreign countries in 1953, and industrial production was already available in the 1960s. In 1982, there was also the production and application of stomach medicine in China. Directly starting from DL-carnitine, using camphoric acid, N-acetyl-D-glutamic acid or ethylbenzoyl-L-(+) tartaric acid as the splitting agent, chemical resolution was carried out to obtain L-carnitine. However, D-carnitine racemization is difficult and cannot be recycled, and industrial production still needs breakthrough progress. (4) enzymatic transformation. This is the most studied and promising method. Selective hydrolysis resolution can be carried out using enzymes of microbial origin. For example, the amidase of Pseudomonas and other microorganisms can be used to selectively hydrolyze DL-carnitine amide or carnitine nitrile to produce L-carnitine with an optical purity of more than 99%. In addition, L-carnitine can be prepared by enzymatic conversion of β-dehydrocarnitine, enzymatic hydrolysis of trans-croton betaine and enzymatic hydroxylation of γ-butyl betaine. At present, there are only students from Switzerland, Italy, Japan and other countries in the world. The Institute of Microbiology in Jiangsu Province of China is also carrying out research on enzymatic transformation. |
spontaneous combustion temperature | >365°C |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |