The relationship between betaine, choline and methionine (repost)

1 Chemical structure and physicochemical properties of betaine the chemical name of betaine is 1muryl-carboxyl-N.NMUR-trimethyl aminoethyl ester. CH3 | structural formula is: CH3-N-CH2-COOH | CH3 belongs to quaternary amine alkali, with a content of 117.15, usually contains a molecule of crystalline water, amphoteric, water-soluble, neutral, white crystal, sweet, its boiling point is 273 ℃, very soluble in water, soluble in methanol, acetic acid, slightly soluble in ether, easy to dissolve, easy to decompose trimethylamine in strong alkali solution Its hydrochloride is not easy to dissolve, and betaine is a non-toxic substance. 2 methods for the determination of betaine the determination of betaine includes spectrophotometry (AOAC,1984) and high performance liquid chromatography (Rajakgla,1983). It is generally believed that the operation of spectrophotometry is complex, the analysis time is long, and the accuracy is poor. High performance liquid chromatography only needs to use appropriate chromatographic columns, such as amino acid column (Vialle,1981) and sodium cation exchange resin column, to detect by differential analysis photodetector or ultraviolet variable wavelength detector (190nm). The method is accurate, rapid and reproducible, but the high performance liquid chromatograph is expensive, which limits the popularization of the method. 3 the biological function of betaine 3.1Betaine as a methyl donor is necessary for the synthesis of methionine, carnitine, creatine, phospholipid, epinephrine, ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) and other substances with major physiological functions (Baker et al., 1985 Frontien et al., 1994), and the role of methylation in the nervous system, immune system, urinary system and cardiac blood system, it is believed that stable methyl donors are needed in both growing and adult animals. It is generally believed that animals can not synthesize methyl by themselves, so they need to have methyl-rich substances in food, and their molecules have reactive methyl, thus participating in the physiological function of animals. This kind of methyl-rich substance is called "methyl donor". The methyl (that is, effective methyl) that is easy to participate in this reaction is the methyl connected with nitrogen or sulfur atoms, such as betaine, methionine, choline and so on (Vogt,1967). Methionine, choline and betaine have different physiological functions, which can not be replaced by each other in this respect, but as far as methyl donors are concerned, they can replace each other on the basis of their unique physiological functions. However, Shen Tong (1998) reported that some biochemical reactions require different methyl sources. The common role of methionine, choline and betaine is methyl donor. In animals, methionine is synthesized by choline to provide methyl, but choline itself does not act as a methyl donor. Choline must be oxidized to betaine in the mitochondria to play the role of methyl donor, while betaine can no longer be reduced to choline. Betaine can transfer methyl to homocysteine to synthesize methionine, which is metabolized by methionine in the body, which is almost free of this amino acid in natural proteins, and the new homocysteine can further accept the converted methyl. In the above cycle, there is no new methionine molecule, in this cycle, methionine simply transfers the methyl provided by betaine to other previous reactions. So betaine cannot come back to replace methionine to synthesize protein, but if choline or betaine is in short supply, the transmethylation cycle is inhibited because there is not enough methyl transfer to homocysteine for methionine synthesis. Therefore, methyl will have to be provided by methionine, which cannot be regenerated in the diet, thus weakening the synthesis of protein and decreasing the utilization of methionine. Cook (1994) believes that if methionine is oversupplied and choline and betaine are deficient, then a large amount of homocysteine accumulates in the body, resulting in diseases such as tibial achondroplasia and atherosclerosis. This explains why there is enough choline and betaine in the diet to meet the need for unstable methyl. In addition, choline needs to be converted to betaine to play the role of methyl donor, while betaine can not be reduced to choline. Some experiments have shown that betaine, as a common intermediate metabolite in animals, is formed by the oxidation of choline by hepatic Flavin protease. This reaction needs the participation of VB12 and is easily inhibited by nickel, cobalt and iron salts. In the absence of riboflavin and the presence of coccidia, the reaction will also be inhibited, affecting the efficiency of choline. Direct use of betaine reduces the oxidation process of conversion from choline to betaine, so direct use of betaine will be more effective (Lowry,1978). From the biochemical pathway of methyl conversion cycle, it can be seen that choline is converted to betaine when choline is used as methyl donor, but betaine can no longer be reduced to choline, and betaine can not play the role of other functions of choline. In addition, for chicks, the choline synthesized by phosphatidylethanolamine and methyl methionine is not enough to meet their needs, so chicks have an absolute choline requirement that cannot be met by betaine or methionine. 3.2 Metabolism of Betaine and Amino acids and proteins Finkelstein et al. (1974, 1982), Huang Dayou (1983). In the study of human homocysteine urine, it was found that the addition of betaine could significantly increase the methionine content in the liver. Xue et al. (1986) found a significant increase in methionine circulation in the liver of sheep and mice fed with betaine. This shows that there is a close relationship between betaine and methionine metabolism. On the one hand, betaine can provide active methyl more effectively than methionine, which reduces the consumption of methionine. On the other hand, betaine can increase the total activity and specific activity of betaine homocysteine-S-methyltransferase (BHMT) in animal liver, promote the transformation of homocysteine to methionine, and has the effect of net methionine increase. Feng Jie (1996) and Zhou Hongsong (1997) added betaine to the diet of fattening pigs. the results showed that the contents of glycine and serine in pig serum increased significantly, which may be due to the formation of dimethylglycine after transmethylation and the formation of glycine and serine after demethylation. Xu Zirong (1997) showed that the addition of betaine to feed increased the proportion of RNA/DNA in longissimus muscle of pig and breast muscle of broilers, which meant an increase in protein synthesis. Wang Yizhen (1998) reported that the addition of different doses of betaine (600, 1300, 2000 and 2700 mg / kg) significantly changed the carcass composition and meat quality of chicks, and the breast muscle percentage was significantly improved, of which the 2000mg/kg group was the best, which was 16.14% higher than that of the group without betaine (P0.05). 3.3.Betaine involved in fat metabolism Sandarson (1990), Mekinley (1990), Shette (1993) and Li Xiubo (1995) conducted comparative experiments between betaine and choline, respectively. It was found that animals fed betaine had lower body fat, more uniform body fat distribution, loose meat, delicious taste, and increased meat yield by 3.7%. It was reported from Yuyan (1999) that betaine substituted for methionine and choline could significantly reduce the content of serum triglyceride, increase the content of serum phospholipid, and decrease the percentage of abdominal fat and liver fat in broilers. Feng Jie (1996), Ma Yulong (1998) and Wang Yizhen (1998) showed that betaine could significantly reduce the content of fat in animal liver, carcass backfat thickness of pigs and abdominal fat rate of poultry. It was found that betaine could significantly increase the content of very low density lipoprotein in serum (Ma Yulong, 1998) and promote the synthesis of phospholipids in laying hens, while phospholipids could reduce the activity of lipase (Kadir et al., 1995) and the content of triglycerides in the liver of mice. It is concluded that by promoting the synthesis of phospholipids, betaine reduces the activity of lipogenic enzymes in the liver on the one hand, and promotes the synthesis of lipoproteins in the liver on the other hand. Very low density lipoprotein is the main apolipoprotein used to carry endogenous triglycerides, thus promoting the migration of fat in the liver and reducing the content of triglycerides in the liver. Triglycerides account for about 99% of animal body fat and are the main form of energy stored by animals. Its decomposition process is the degradation process of body fat. The decrease of the content of serum triglyceride indicates the enhancement of fat decomposition, which is directly reflected in the decrease of abdominal fat rate. It can be seen from the above that betaine plays an anti-fatty liver effect by reducing body fat by promoting fat decomposition and inhibiting fat production. 3.4 effect of betaine on osmotic regulation and efficacy of anticoccidial drugs Betaine can regulate and buffer osmotic stress. When the body is faced with stress (such as high temperature, diarrhea, coccidiosis, etc.), the external osmotic pressure changes dramatically, and the cells begin to produce or absorb betaine to maintain normal osmotic pressure balance, prevent water loss and salt invasion, and improve the function of sodium and potassium pump, which is helpful to protect the normal function of gastrointestinal tract, so as to reduce the harm degree of stress and maintain good health. And reduce the occurrence of death. Hall (1995) reported that betaine could significantly reduce the stress during transportation and accelerate the body weight recovery of cattle before and after long-distance transportation. Ding Xicheng et al. (1999) found that betaine could improve the disorder of electrolytic balance caused by giant Eimeria infection and significantly inhibit the reproduction of merozoites. Peng Xinyu et al (1999) reported that the addition of betaine in the feed containing polyether antibiotics could increase the weight gain and the anti-coccidial index of polyether antibiotics in broilers infected with Eimeria tenella. In particular, the weight gain of Maduramycin plus betaine group was the most significant (the relative weight gain rate increased by 19%), and the anti-coccidial index increased by 24.7%. It can be seen that betaine is an effective buffer for osmotic shock of organism cells, and can protect intestinal mucosal cells together with ion carrier anti-coccidial drugs, ensure the normal function of cells, and improve the efficacy of anti-coccidial drugs. 3.5 Food attraction of betaine: since Finnish scientists discovered that betaine has a special food attraction to aquatic animals in the 1970s, betaine as a food attractant in aquaculture has been widely recognized and applied. Although the artificial bait used in aquaculture is full of nutrients, it is still a boring food for aquatic animals. In addition to vision and touch, smell and taste play an important role in fish feeding. Studies on fish and shrimp by some scholars in the United States, Japan and other countries have shown that betaine in 0.0001mol/L can cause the taste response of all fish. Clarke (1994) reported that betaine had no significant effect on the growth and death of salmon in fresh water, but the growth of salmon was significantly improved by feeding betaine in seawater. The experiment of Xue Yongrui (1995) on carp showed that the yield of 0.1%, 0.2% and 0.3% betaine in feed was 16.5%, 17.4% and 21.5% higher than that of the control group, respectively. Yan Li et al. (1994) added betaine 0.3%, betaine hydrochloride 0.5% and fine product 0.3% to carp feed, respectively, and the weight gain rate increased by 49.23%, 41.78% and 43.84% respectively compared with the control group, and the feed coefficient decreased by 24.16%, 22.13% and 14.13%, respectively. Chang Zhizhou et al. (1982) added 1.25% betaine to the river crab diet, the net weight gain of the river crab increased by 95.3%, the survival rate increased by 38%, and faster growth rate and higher survival rate could be obtained. -- good information, thank you, landlord! -- collected Thank you, landlord-- the information is good, but to be honest, I don't believe in Chinese arguments and the science is not rigorous. Some things have to be accepted dialectically-betaine as a whole has good use value. -- good information. I just need it. Thank you for your collection. Thank you, landlord-- although it is so good, it has not been recognized by everyone-- collected, thank you, is there any good information? -- how betaine is really used now? why didn't you say it?-- I've seen it before. Very valuable information!-- study! Thank you, landlord.