What is the relationship between betaine, choline and methionine?
The relationship between betaine, choline and methionine (repost)
1 Chemical structure and physicochemical properties of betaine
The chemical name of betaine is 1-carboxy-N.N.N-trimethylaminoethanoyl lactone.
CH3
|
The structural formula is: CH3-N-CH2-COOH
|
CH3
It belongs to the quaternary ammonium alkaloid class of substances, with a molecular weight of 117.15, usually contains one molecule of water of crystallization, is amphoteric, its aqueous solution is neutral, is a white crystal with a sweet taste, its boiling point is 273°C, is extremely soluble in water, soluble in methanol, acetic acid, etc., slightly soluble in ether, is extremely deliquescent, easily decomposes to release trimethylamine in concentrated strong alkali solutions, while its hydrochloride is not easily deliquescent, 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). Spectrophotometry is generally considered to be complex to operate, takes a long time to analyze, and has poor accuracy. High-performance liquid chromatography, however, only requires the use of a suitable chromatographic column, such as an amino acid column (Vialle, 1981), a sodium-type cation exchange resin column, with detection by a differential refractive detector or a variable-wavelength ultraviolet detector (190 nm). This method is accurate, rapid, and highly reproducible, but the high cost of high-performance liquid chromatography instruments places certain limits on the promotion of this method.
3 Biological functions of betaine
3.1 Betaine as a methyl donor
Because methyl groups are essential for the synthesis of methionine, carnitine, creatine, phospholipids, adrenaline, ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) and other substances with major physiological roles (Baker et al., 1985; Frontien et al., 1994), and because of the role played by methylation reactions in the nervous system, immune system, urinary system and cardiovascular system, it is believed that both growing animals and adult animals require a stable methyl donor. It is generally believed that animals cannot synthesize methyl groups themselves, and require methyl-rich substances in the food, whose molecules contain readily reactive methyl groups and thus participate in animal physiological functions; such methyl-rich substances are called "methyl donors," and the methyl groups that readily participate in this reaction (i.e., effective methyl groups) are methyl groups attached to a nitrogen atom or a sulfur atom, such as betaine, methionine, choline, etc. (Vogt, 1967).
These three substances, methionine, choline and betaine, each have their own different physiological functions, and in this respect the three cannot substitute for one another, but as regards methyl donation, the three can substitute for one another on the basis of satisfying their respective specific physiological functions. However, Shen Tong (1998) reported that certain biochemical reactions require different methyl sources.
The common function of methionine, choline and betaine is as methyl donors. In animals, the synthesis of methionine relies on choline to provide methyl groups, while choline itself does not act as a methyl donor. Choline must be oxidized to betaine within the mitochondria in order to exert its methyl-donor function, while betaine can no longer be reduced back to choline. Betaine can transfer a methyl group to homocysteine to synthesize methionine; homocysteine is produced by the metabolism of methionine in the body, is almost absent from natural proteins, and the newly formed homocysteine can further accept the transferred methyl group. In this cyclic process, there are no newly formed methionine molecules; in this cyclic process, methionine simply transfers onward to the other preceding reactions the methyl group provided by betaine. Therefore betaine cannot come back to replace methionine in synthesizing protein, but if the supply of choline or betaine is insufficient, the transmethylation cycle is inhibited, because there is not enough methyl to transfer to homocysteine for methionine synthesis. Therefore the methyl groups will have to be provided by methionine, which cannot be regenerated from the diet, thereby weakening protein synthesis and reducing the utilization rate of methionine. Cook (1994) believes that if methionine is supplied in excess while choline and betaine are deficient, then large amounts of homocysteine accumulate in the body, producing conditions such as tibial dyschondroplasia and atherosclerosis. This explains why the diet must contain sufficient choline and betaine to meet the need for labile methyl groups.
In addition, choline must be converted to betaine in order to exert its methyl-donor function, while betaine cannot be reduced back to choline. Tests have shown that betaine, as an intermediate metabolite commonly present in animals, is formed from choline under oxidation by liver flavoprotein enzymes; this reaction requires the participation of VB12, and is easily inhibited by nickel, cobalt and iron salts, and is also inhibited when riboflavin is deficient and when coccidia are present, affecting the exertion of choline's efficacy. Direct use of betaine reduces the oxidation process of converting choline to betaine, so direct use of betaine will be more effective (Lowry, 1978).
From the biochemical pathway of the transmethylation cycle, it can be seen that when choline acts as a methyl donor it is converted into betaine, but betaine can no longer be reduced back to choline, and betaine cannot perform choline's other functions. In addition, for chicks, the choline synthesized from phosphatidylethanolamine and from methyl groups provided by methionine is insufficient to meet their needs, so chicks have an absolute choline requirement that betaine or methionine cannot satisfy.
3.2 Betaine and the metabolism of amino acids and proteins
Finkelstein et al. (1974; 1982) and Huang Dayou (1983), in studies of human homocystinuria, found that the addition of betaine can markedly increase the methionine content in the liver. Xue et al. (1986), after feeding betaine to sheep and rats, found that the methionine cycle in the liver was markedly enhanced. This shows that betaine is closely related to methionine metabolism. On the one hand, betaine can provide active methyl groups more effectively than methionine, reducing methionine's consumption in providing methyl groups; on the other hand, betaine can increase the total activity and specific activity of betaine-homocysteine-S-methyltransferase (BHMT) in animal liver, promoting the conversion of homocysteine to methionine, and has the effect of net-increasing methionine. Feng Jie (1996) and Zhou Hongsong (1997) added betaine to the diet of finishing pigs and found that the contents of glycine and serine in pig serum were markedly elevated, possibly because betaine, after transmethylation, forms dimethylglycine, which after further demethylation forms glycine and serine. Xu Zirong (1997) showed that adding betaine to feed increased the RNA/DNA ratio in the longissimus dorsi muscle of pigs and the breast muscle of broilers, which means an increase in protein synthesis. Wang Yizhen (1998) reported that adding different doses of betaine (600, 1300, 2000, 2700 mg/kg) all markedly changed the carcass composition and meat quality of chicks, with the breast muscle percentage markedly increased, among which the 2000 mg/kg group had the best effect, increasing by 16.14% (P<0.01),添加蛋氨酸组 2000mg/kg提高了5.26%(P>0.05)。
3.3 Betaine participates in fat metabolism
Sandarson (1990), Mekinley (1990), Shette (1993) and Li Xiubo (1995) respectively conducted comparative trials of betaine and choline, and found that animals fed betaine had lower body fat, more uniform body fat distribution, looser meat, a tasty flavor, and an increase in the meat production of young poultry of 3.7%. Cong Yuyan (1999) reported that betaine replacing methionine and choline could significantly reduce the serum triglyceride content of broilers and increase the serum phospholipid content, with the abdominal fat rate and liver fat both markedly decreased. Feng Jie (1996), Ma Yulong (1998) and Wang Yizhen (1998) found in their research that betaine can markedly reduce the fat content in animal liver and greatly reduce the backfat thickness of pig carcasses and the abdominal fat rate of poultry. Research has found that betaine can markedly increase the content of very-low-density lipoprotein in the serum of laying hens (Ma Yulong, 1998), promoting the synthesis of phospholipids in the body, and phospholipids can reduce the activity of lipogenic enzymes in mouse liver (Kadir et al., 1995) and the triglyceride content.
From this it can be concluded that betaine, by promoting the synthesis of phospholipids in the body, on the one hand reduces the activity of lipogenic enzymes in the liver, and on the other hand promotes the synthesis of lipoproteins in the liver, among which very-low-density lipoprotein is the main apolipoprotein used to transport endogenous triglycerides, thereby promoting the migration of fat in the liver and reducing the triglyceride content in the liver. Triglycerides account for about 99% of animal body fat and are the main form in which animals store energy; their decomposition process is the degradation process of body fat. A decrease in serum triglyceride content indicates that fat decomposition is strengthened, and this is directly reflected in the reduction of the abdominal fat rate. From the above it can be seen that betaine reduces body fat and plays an anti-fatty-liver role through both promoting fat decomposition and inhibiting fat formation.
3.4 The effect of betaine on osmotic pressure regulation and on the efficacy of anticoccidial drugs
Betaine has a regulating and buffering function against abrupt changes in osmotic pressure. When the body faces stress (such as high temperature, diarrhea, coccidiosis infection, etc.), the external osmotic pressure changes abruptly, and the cells themselves begin to produce or absorb betaine to maintain normal osmotic pressure balance, prevent water loss and salt intrusion, and can enhance the function of the sodium-potassium pump, which is beneficial for protecting the normal function of the gastrointestinal tract, thereby reducing the degree of harm from stress, maintaining good health, and reducing the occurrence of death. Hall (1995) reported that feeding betaine to cattle before and after long-distance transport can markedly reduce transport stress and speed up the recovery of cattle body weight. Ding Xicheng et al. (1999) found in experiments that betaine improves the electrolyte balance disorder caused by Eimeria maxima infection in animals and has a marked inhibitory effect on the reproduction of Eimeria maxima schizonts. Peng Xinyu et al. (1999) reported that for broilers infected with Eimeria tenella, applying feed containing polyether antibiotics supplemented with betaine can increase broiler weight gain and the anticoccidial index of polyether antibiotics; in particular, the maduramicin plus betaine group had the most marked weight gain (relative weight gain rate increased by 19%), and the anticoccidial index increased by 24.7%. It can be seen that betaine is an effective buffer against abrupt changes in the osmotic pressure of biological cells, and can act together with ionophore anticoccidial drugs to protect intestinal mucosal cells, ensure the normal function of cells, and improve the efficacy of anticoccidial drugs.
3.5 The feeding-attractant effect of betaine:
Since scientists in Finland discovered in the 1970s that betaine has a special feeding-attractant effect on aquatic animals, betaine has been widely recognized and applied as a feeding attractant in the aquaculture industry. Although the artificial bait put into aquaculture is comprehensive in nutritional composition, it is still a bland food for aquatic animals. Apart from vision and touch, the roles of smell and taste in fish feeding are particularly important. Studies by some scholars in the United States, Japan and other countries on fish and shrimp show that 0.0001 mol/L betaine can trigger a taste receptor response in all fish. Clarke (1994) reported that in fresh water betaine had no marked effect on the growth or mortality of Atlantic salmon, while in seawater feeding a diet containing betaine had a marked effect on improving the growth of this fish. Xue Yongrui (1995), in trials on carp, showed that adding 0.1%, 0.2% and 0.3% betaine to the feed increased yield by 16.5%, 17.4% and 21.5% respectively compared with the control group. Yan Youli et al. (1994) added 0.3% betaine, 0.5% crude betaine hydrochloride and 0.3% refined product respectively to carp feed, among which the weight gain rates increased by 49.23%, 41.78% and 43.84% respectively compared with the control group, and the feed conversion ratios decreased by 24.16%, 22.13% and 14.13% respectively. Chang Zhizhou et al. (1982) added 1.25% betaine to river crab bait, and the net weight gain of river crabs increased by 95.3% and the survival rate increased by 38%, making it possible to obtain a faster growth rate and a higher survival rate.
--------------------------------------
Good material, thanks to the original poster!!!
--------------------------------------
Bookmarked, thanks to the original poster
--------------------------------------
The material is not bad, but to be honest, I don't quite trust Chinese arguments; the science is not rigorous, and some things have to be accepted dialectically
--------------------------------------
Overall, betaine still has very good utilization value.
--------------------------------------
Good material, just what I needed, thanks to the original poster
--------------------------------------
Bookmarked, thanks to the original poster
--------------------------------------
Although it is said to be so good, it still has not gained everyone's general recognition
--------------------------------------
Bookmarked, thanks, what other good material is there?
--------------------------------------
How betaine is actually used in practice, why wasn't that discussed.
--------------------------------------
I read this before, very valuable material!
--------------------------------------
Learned something! Thanks to the original poster..
The chemical name of betaine is 1-carboxy-N.N.N-trimethylaminoethanoyl lactone.
CH3
|
The structural formula is: CH3-N-CH2-COOH
|
CH3
It belongs to the quaternary ammonium alkaloid class of substances, with a molecular weight of 117.15, usually contains one molecule of water of crystallization, is amphoteric, its aqueous solution is neutral, is a white crystal with a sweet taste, its boiling point is 273°C, is extremely soluble in water, soluble in methanol, acetic acid, etc., slightly soluble in ether, is extremely deliquescent, easily decomposes to release trimethylamine in concentrated strong alkali solutions, while its hydrochloride is not easily deliquescent, 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). Spectrophotometry is generally considered to be complex to operate, takes a long time to analyze, and has poor accuracy. High-performance liquid chromatography, however, only requires the use of a suitable chromatographic column, such as an amino acid column (Vialle, 1981), a sodium-type cation exchange resin column, with detection by a differential refractive detector or a variable-wavelength ultraviolet detector (190 nm). This method is accurate, rapid, and highly reproducible, but the high cost of high-performance liquid chromatography instruments places certain limits on the promotion of this method.
3 Biological functions of betaine
3.1 Betaine as a methyl donor
Because methyl groups are essential for the synthesis of methionine, carnitine, creatine, phospholipids, adrenaline, ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) and other substances with major physiological roles (Baker et al., 1985; Frontien et al., 1994), and because of the role played by methylation reactions in the nervous system, immune system, urinary system and cardiovascular system, it is believed that both growing animals and adult animals require a stable methyl donor. It is generally believed that animals cannot synthesize methyl groups themselves, and require methyl-rich substances in the food, whose molecules contain readily reactive methyl groups and thus participate in animal physiological functions; such methyl-rich substances are called "methyl donors," and the methyl groups that readily participate in this reaction (i.e., effective methyl groups) are methyl groups attached to a nitrogen atom or a sulfur atom, such as betaine, methionine, choline, etc. (Vogt, 1967).
These three substances, methionine, choline and betaine, each have their own different physiological functions, and in this respect the three cannot substitute for one another, but as regards methyl donation, the three can substitute for one another on the basis of satisfying their respective specific physiological functions. However, Shen Tong (1998) reported that certain biochemical reactions require different methyl sources.
The common function of methionine, choline and betaine is as methyl donors. In animals, the synthesis of methionine relies on choline to provide methyl groups, while choline itself does not act as a methyl donor. Choline must be oxidized to betaine within the mitochondria in order to exert its methyl-donor function, while betaine can no longer be reduced back to choline. Betaine can transfer a methyl group to homocysteine to synthesize methionine; homocysteine is produced by the metabolism of methionine in the body, is almost absent from natural proteins, and the newly formed homocysteine can further accept the transferred methyl group. In this cyclic process, there are no newly formed methionine molecules; in this cyclic process, methionine simply transfers onward to the other preceding reactions the methyl group provided by betaine. Therefore betaine cannot come back to replace methionine in synthesizing protein, but if the supply of choline or betaine is insufficient, the transmethylation cycle is inhibited, because there is not enough methyl to transfer to homocysteine for methionine synthesis. Therefore the methyl groups will have to be provided by methionine, which cannot be regenerated from the diet, thereby weakening protein synthesis and reducing the utilization rate of methionine. Cook (1994) believes that if methionine is supplied in excess while choline and betaine are deficient, then large amounts of homocysteine accumulate in the body, producing conditions such as tibial dyschondroplasia and atherosclerosis. This explains why the diet must contain sufficient choline and betaine to meet the need for labile methyl groups.
In addition, choline must be converted to betaine in order to exert its methyl-donor function, while betaine cannot be reduced back to choline. Tests have shown that betaine, as an intermediate metabolite commonly present in animals, is formed from choline under oxidation by liver flavoprotein enzymes; this reaction requires the participation of VB12, and is easily inhibited by nickel, cobalt and iron salts, and is also inhibited when riboflavin is deficient and when coccidia are present, affecting the exertion of choline's efficacy. Direct use of betaine reduces the oxidation process of converting choline to betaine, so direct use of betaine will be more effective (Lowry, 1978).
From the biochemical pathway of the transmethylation cycle, it can be seen that when choline acts as a methyl donor it is converted into betaine, but betaine can no longer be reduced back to choline, and betaine cannot perform choline's other functions. In addition, for chicks, the choline synthesized from phosphatidylethanolamine and from methyl groups provided by methionine is insufficient to meet their needs, so chicks have an absolute choline requirement that betaine or methionine cannot satisfy.
3.2 Betaine and the metabolism of amino acids and proteins
Finkelstein et al. (1974; 1982) and Huang Dayou (1983), in studies of human homocystinuria, found that the addition of betaine can markedly increase the methionine content in the liver. Xue et al. (1986), after feeding betaine to sheep and rats, found that the methionine cycle in the liver was markedly enhanced. This shows that betaine is closely related to methionine metabolism. On the one hand, betaine can provide active methyl groups more effectively than methionine, reducing methionine's consumption in providing methyl groups; on the other hand, betaine can increase the total activity and specific activity of betaine-homocysteine-S-methyltransferase (BHMT) in animal liver, promoting the conversion of homocysteine to methionine, and has the effect of net-increasing methionine. Feng Jie (1996) and Zhou Hongsong (1997) added betaine to the diet of finishing pigs and found that the contents of glycine and serine in pig serum were markedly elevated, possibly because betaine, after transmethylation, forms dimethylglycine, which after further demethylation forms glycine and serine. Xu Zirong (1997) showed that adding betaine to feed increased the RNA/DNA ratio in the longissimus dorsi muscle of pigs and the breast muscle of broilers, which means an increase in protein synthesis. Wang Yizhen (1998) reported that adding different doses of betaine (600, 1300, 2000, 2700 mg/kg) all markedly changed the carcass composition and meat quality of chicks, with the breast muscle percentage markedly increased, among which the 2000 mg/kg group had the best effect, increasing by 16.14% (P<0.01),添加蛋氨酸组 2000mg/kg提高了5.26%(P>0.05)。
3.3 Betaine participates in fat metabolism
Sandarson (1990), Mekinley (1990), Shette (1993) and Li Xiubo (1995) respectively conducted comparative trials of betaine and choline, and found that animals fed betaine had lower body fat, more uniform body fat distribution, looser meat, a tasty flavor, and an increase in the meat production of young poultry of 3.7%. Cong Yuyan (1999) reported that betaine replacing methionine and choline could significantly reduce the serum triglyceride content of broilers and increase the serum phospholipid content, with the abdominal fat rate and liver fat both markedly decreased. Feng Jie (1996), Ma Yulong (1998) and Wang Yizhen (1998) found in their research that betaine can markedly reduce the fat content in animal liver and greatly reduce the backfat thickness of pig carcasses and the abdominal fat rate of poultry. Research has found that betaine can markedly increase the content of very-low-density lipoprotein in the serum of laying hens (Ma Yulong, 1998), promoting the synthesis of phospholipids in the body, and phospholipids can reduce the activity of lipogenic enzymes in mouse liver (Kadir et al., 1995) and the triglyceride content.
From this it can be concluded that betaine, by promoting the synthesis of phospholipids in the body, on the one hand reduces the activity of lipogenic enzymes in the liver, and on the other hand promotes the synthesis of lipoproteins in the liver, among which very-low-density lipoprotein is the main apolipoprotein used to transport endogenous triglycerides, thereby promoting the migration of fat in the liver and reducing the triglyceride content in the liver. Triglycerides account for about 99% of animal body fat and are the main form in which animals store energy; their decomposition process is the degradation process of body fat. A decrease in serum triglyceride content indicates that fat decomposition is strengthened, and this is directly reflected in the reduction of the abdominal fat rate. From the above it can be seen that betaine reduces body fat and plays an anti-fatty-liver role through both promoting fat decomposition and inhibiting fat formation.
3.4 The effect of betaine on osmotic pressure regulation and on the efficacy of anticoccidial drugs
Betaine has a regulating and buffering function against abrupt changes in osmotic pressure. When the body faces stress (such as high temperature, diarrhea, coccidiosis infection, etc.), the external osmotic pressure changes abruptly, and the cells themselves begin to produce or absorb betaine to maintain normal osmotic pressure balance, prevent water loss and salt intrusion, and can enhance the function of the sodium-potassium pump, which is beneficial for protecting the normal function of the gastrointestinal tract, thereby reducing the degree of harm from stress, maintaining good health, and reducing the occurrence of death. Hall (1995) reported that feeding betaine to cattle before and after long-distance transport can markedly reduce transport stress and speed up the recovery of cattle body weight. Ding Xicheng et al. (1999) found in experiments that betaine improves the electrolyte balance disorder caused by Eimeria maxima infection in animals and has a marked inhibitory effect on the reproduction of Eimeria maxima schizonts. Peng Xinyu et al. (1999) reported that for broilers infected with Eimeria tenella, applying feed containing polyether antibiotics supplemented with betaine can increase broiler weight gain and the anticoccidial index of polyether antibiotics; in particular, the maduramicin plus betaine group had the most marked weight gain (relative weight gain rate increased by 19%), and the anticoccidial index increased by 24.7%. It can be seen that betaine is an effective buffer against abrupt changes in the osmotic pressure of biological cells, and can act together with ionophore anticoccidial drugs to protect intestinal mucosal cells, ensure the normal function of cells, and improve the efficacy of anticoccidial drugs.
3.5 The feeding-attractant effect of betaine:
Since scientists in Finland discovered in the 1970s that betaine has a special feeding-attractant effect on aquatic animals, betaine has been widely recognized and applied as a feeding attractant in the aquaculture industry. Although the artificial bait put into aquaculture is comprehensive in nutritional composition, it is still a bland food for aquatic animals. Apart from vision and touch, the roles of smell and taste in fish feeding are particularly important. Studies by some scholars in the United States, Japan and other countries on fish and shrimp show that 0.0001 mol/L betaine can trigger a taste receptor response in all fish. Clarke (1994) reported that in fresh water betaine had no marked effect on the growth or mortality of Atlantic salmon, while in seawater feeding a diet containing betaine had a marked effect on improving the growth of this fish. Xue Yongrui (1995), in trials on carp, showed that adding 0.1%, 0.2% and 0.3% betaine to the feed increased yield by 16.5%, 17.4% and 21.5% respectively compared with the control group. Yan Youli et al. (1994) added 0.3% betaine, 0.5% crude betaine hydrochloride and 0.3% refined product respectively to carp feed, among which the weight gain rates increased by 49.23%, 41.78% and 43.84% respectively compared with the control group, and the feed conversion ratios decreased by 24.16%, 22.13% and 14.13% respectively. Chang Zhizhou et al. (1982) added 1.25% betaine to river crab bait, and the net weight gain of river crabs increased by 95.3% and the survival rate increased by 38%, making it possible to obtain a faster growth rate and a higher survival rate.
--------------------------------------
Good material, thanks to the original poster!!!
--------------------------------------
Bookmarked, thanks to the original poster
--------------------------------------
The material is not bad, but to be honest, I don't quite trust Chinese arguments; the science is not rigorous, and some things have to be accepted dialectically
--------------------------------------
Overall, betaine still has very good utilization value.
--------------------------------------
Good material, just what I needed, thanks to the original poster
--------------------------------------
Bookmarked, thanks to the original poster
--------------------------------------
Although it is said to be so good, it still has not gained everyone's general recognition
--------------------------------------
Bookmarked, thanks, what other good material is there?
--------------------------------------
How betaine is actually used in practice, why wasn't that discussed.
--------------------------------------
I read this before, very valuable material!
--------------------------------------
Learned something! Thanks to the original poster..