Showing posts with label vitamin C. Show all posts
Showing posts with label vitamin C. Show all posts
Category: Vitamin C
Scurvy - Disease of vitamin C deficiency
Scurvy is a historically documented disease and was encountered in earlier days by sailors on long voyages foregoing fresh fruits and vegetables.
Though many animals can synthesize it in their body and are free from scurvy, unfortunately man has to depend on his food sources for vitamin C.
Health care and nutrition guidelines recommend a daily intake of 75 to 100mg of ascorbic acid (vitamin C).
Inadequate or irregular intake of ascorbic acid can lead to clinical manifestations of this disease in two to three months.
Initial symptoms of scurvy disease include lethargy, tiredness and malaise.
With chronic deficiency scurvy progresses and is characterised by spongy gums, bleeding gums, loosened teeth, bleeding beneath the skin, bleeding from the mucous membranes, extreme weakness, myalgia, anemia, pain in the bones, easy bruising and retarded wound healing, oedema, perifolicular hemorrhage and corkscrew hairs and depression.
A relationship appears to be present between alcoholism and vitamin C.
When blood levels of alcohol are high, vitamin C appears to be excreted in urine in greater quantities causing deficiency.
This can be treated by supplementation of ascorbic acid in high doses till recovery.
For more information on vitamin C deficiency please visit my web site http://www.thedynamicnature.com.
Vitamin C vegetables - richest sources
Presence of vitamin C in vegetables is quite significant. However vitamin C decomposes in many of the cooking processes.
Longer cooking duration and boiling for longer time causes reduction in the availability of vitamin C.
Another loss of vitamin C from vegetables is by leeching into the water used in cooking.
To safe guard the nutritional value, immediate refrigeration, cooking in smaller quantities of water and avoiding prolonged cooking may be resorted to.
Discussed here under are some of the high vitamin c sources.
Red pepper (Capsicum sp.)
Red pepper is one of the high vitamin C foods among vegetables (190 mg per 100 grams). Red pepper is also known as capsicum or just pepper.Red pepper belongs to the family Solanaceae to which tomato also belongs. Red pepper is a native plant of Americas.
Red pepper are used raw in salads and are also cooked and used in the preparation of various dishes. Red pepper is also preserved by drying, freezing or pickling.
Broccoli (Brassica oleracea)
Broccoli is one of the high vitamin C sources among vegetables. Broccoli contains 90 mg of vitamin C per 100 grams of the weight. Broccoli belongs the cabbage family Brassicaceae. Broccoli resembles cauliflower and has green colored flower head.It is believed that broccoli has evolved from wild cabbage plants in Europe.
Broccoli is rich in minerals and antioxidants. Broccoli has diindolylmethane and selenium which have anti-cancer properties.
Brussels sprouts (Brassica sp.)
Brussels sprouts are rich with Vitamin C among vegetables (80 mg per 100 grams).Brussels sprouts belong to the cabbage family Brassicaceae prevalent in Europe. Brussels sprouts resemble cabbages and are miniature in size, 2.5-4 Cm in diameter appearing as green leafy buds. Brussels sprouts particularly prefer cooler temperatures of the range between 7-24 C. giving high yields at 15-18 C.
Cauliflower (Brassica sp.)
Cauliflower contains 40 mg of vitamin C per 100 gms.of these vegetables. Cauliflowers belong to the cabbage family Brassicaceae.They are grown in Europe and its tropical varieties are grown in Asian countries.
Cauliflower is an annual plant and is propagated by seeds. Cauliflowers are cooked or pickled and have good nutritional density.
Garlic (Allium sativum)
Garlic contain 31 mg of vitamin C per 100 gms of these vegetables.Garlic belongs to the onion family Alliaceae. There is widespread use of garlic, through out the world for medicinal and culinary purposes.
Garlic is very easy to grow and usually is not attacked by pests. Garlic has been found to have antioxidant, anti fungal, antiviral and antibacterial properties.
Spinach (Spinacia oleracea)
Spinach contain 30 mg of vitamin C for every 100 gms. These leafy vegetables belong to the family of Amaranthaceae. Spinach is native to Asia (India and Nepal) and grows to a height of about 30 cms.Spinach is rich in minerals especially iron. Spinach leaves are rich in vitamins C, A, E, K, iron, calcium, copper, phosphorus, zinc and fatty acids.
Cabbage
Cabbages are sources containing 30 mg of vitamin C per 100 gms of these vegetables.Cabbage belong to the family of Brassicaceae and is a herbacious, biennial flowering plant with short stem and crowned mass of leaves.
Cabbage originated from Mediterranean region and is all over the world presently. China and India are the foremost countries in the production of cabbage.
Cabbage is rich in amino acid glutamine which has anti-inflammatory properties.
Potato (Solanum tuberosum)
Potatoes contain 20 mg of vitamin C per 100gms of these tuberous vegetables.Potato belong to the family Solanaceae and is perennial. Potato is native to the Americas and was introduced to Europe in 15th century.
Potato plants are herbaceous and perennial growing to a height of about two feet. There are many varieties of potatoes with different colors, sizes and shapes.
Potato is rich in starch and also contains polyphenols and carotenoids.
Potato contains iron, phosphorus, magnesium, zinc, niacin, riboflavin and thiamine.
Tomato (Solanum lycopersicum)
Tomato are sources containing 10 mg of vitamin C per 100 gms of these vegetables.Tomato vegetables belong to the family Solanaceae and is seasonal, herbaceous and sprawling plant.
Tomato plants usually grow up to 2 meters in height and the stem is woody and weak.
Tomato plant is native to South America and has been introduced to all regions of the world.
Vitamin C and liver - detoxification of body
Vitamin C is an important support in liver detoxification mechanism.
Role of vitamin C in liver detoxification
Vitamin C helps in the detoxification and removal of the harmful substances from the body. Liver as the main blood purifying organ of the body removes the harmful substances from the blood. Most of these toxic substances are absorbed into the body through gastrointestinal system, lungs and skin. Many toxic chemicals are also produced as by-products of biological processes.If these toxic substances are not removed from the blood due some disease or due lack of antioxidants, especially vitamin C, the toxins may accumulate in very important parts of the body like brain and kidney leading to devastating health problems. Depletion or lack of vitamin C impairs the blood purifying mechanism of the liver.
Detoxification takes place in two phases. In phase 1, the toxins are reduced to smaller less harmful fragments. This is achieved by the biological processes like hydrolysis, reduction and oxidation. During this phase 1 detoxification free radicals are formed and in excess they can destroy the cells.
The availability of ascorbic acid and other oxidants at this stage neutralizes the free radicals and protects the cells from the oxidative damages in this phase. In phase 2 of detoxification, the fragmented molecules are bound to sulphate, glycine and glutathione to create new non toxic substance and excreted in bile or urine.
Role of vitamin C in treatment of hepatitis
Ascorbic acid along with hepatic stimulants like alpha lipoic acid and milk thistle have been used successfully in the treatment of viral and chronic hepatitis. Vitamin C (sodium ascorbate) given via intravenous route will help liver detoxification bringing relief in a few days. Affected with hepatitis, the mitochondria may get damaged and free radical scavenging may get upset. This results in excessive free radicals and the resultant destruction of the cells. The presence of vitamin C mops up the free radicals and the conditions improve.Role of vitamin C in treatment of NFLD (Nonalcoholic Fatty Liver Disease)
Steatosis (also called adipose degeneration, fatty degeneration or fatty change) is a process wherein lipids are abnormally retained inside the cells. Steatosis of these cells causes NAFLD.
Vitamin C and liver detoxification
Vitamin C - Heart disease
Home > Vitamin C and heart disease
Vitamin C as an antioxidant and contributor in collagen synthesis, has very crucial role in prevention and treatment of heart disease.
But the nutritional requirement of ascorbic acid is much higher than this for warding off adverse health conditions, especially the ischemic heart disease.
subclinical form of vitamin C deficiency exists in many people leading to diseases like cardiac disease, strokes, diabetes etc.
Vitamin C - heart disease and arterial walls
As the heart pumps blood back to the body all the blood vessels experience pressure, especially arteries.When the blood vessels are healthy, normal blood flow is maintained.
If the arteries are weak, constricted or have deposits in the wall, there is cardiac stress and diseases like hypertension, cardiovascular disease is caused.
Collagen is found in the artery wall and is necessary for the elasticity and tenor of the artery.
Ascorbic acid is necessary for collagen synthesis.
When there is deficiency of vitamin C, the artery walls harden and develop minute cracks and blood leaks into the surrounding tissues.
A focal point inflammatory, disease and infection is formed.
This leads to production of prostaglandin thromboxane.
Ascorbic acid is necessary for collagen synthesis.
When there is deficiency of vitamin C, the artery walls harden and develop minute cracks and blood leaks into the surrounding tissues.
A focal point inflammatory, disease and infection is formed.
This leads to production of prostaglandin thromboxane.
In order to plug these leaking cracks platelets aggregate and lipoproteins are deposited.
The LDL cholesterol in the blood forms further deposits at this point and a plaque is formed.
This leads to narrowing of the blood vessels and to keep up circulation the heart has to pump harder.
Fresh cracks get formed due to pressure and a chain reaction starts leading to further narrowed vessels.
The consumption of ascorbic acid makes the endothelial lining of the artery wall healthy and elastic by proper and sufficient deposits of collagen.
Further ascorbic acid can prevent the plaque formation. Ascorbic acid inhibits the oxidative modification of LDL (low density lipoproteins) and prevents deposits.
Ascorbic acid hinders blood platelets aggregation and the formation of clot.
Ascorbic acid increases the fibrinolytic activity and the dissolution of plaques.
Ascorbic acid restores the characteristics of atherosclerotic arteries back to normalcy by dilation and restores proper blood supply curing cardiac disease.
It is vital for the healthy heart and for protection from cardiac conditions.
Related topics:
Ascorbic acid functions
Health benefits
Vitamin C and Liver
Kidney
Current topic:
Vitamin C and heart disease
Related topics:
Ascorbic acid functions
Health benefits
Vitamin C and Liver
Kidney
Current topic:
Vitamin C and heart disease
Vitamin C and kidney - Oxalate stones
Kidney regulates the plasma levels of vitamin C. The feared formation of oxalate stones due to high vitamin C is unfound. In fact vitamin C helps in the dissolution of other types of kidney stones.
Renal resorption threshold and excretion of vitamin C by kidney
The optimum renal resorption threshold levels of vitamin C in healthy men and women are 1.5 mg/dl and 1.3 mg/dl respectively. The body pool levels of 1500-3000 mg are considered tissue saturation levels of ascorbic acid. Once the plasma levels of vitamin C exceeds this level it is not further resorbed by the kidney and gets excreted in urine.Further the water soluble properties of vitamin C leads to urinary excretion as ascorbic acid in case of elevated levels. In higher plasma levels the half-life of vitamin C is about 30 minutes. When the concentrations are less than the renal resorption threshold the vitamin C is resorbed actively and the half-life is greatly extended in depleted conditions.
Ascorbic acid has an average half-life of about 15-20 days. The half-life is inversely decreases or increases with its intake. The metabolic products of vitamin C, like 2-ketoascorbitol, 2-O-methyl ascorbate, dehydroascorbate and oxalic acid are excreted by the kidney.
Does vitamin C cause Oxalate stones in kidney?
There are various types of kidney stones made up of urate, calcium phosphate, struvite, cystine. Oxalate and urate are the main deposits in renal stones. A section of the medical community believes that ascorbic acid in high doses can cause kidney stones. As one of the by-product of vitamin C metabolism is oxalic acid, it is being concluded that, these ions on combining with calcium, form calcium salt and get deposited in kidney and form stones.There are conflicting reports of studies conducted on these deposits formation. One study conducted on 45,250 men for 6 years and another on 85,557 women for 14 years, had given the conclusion that daily consumption of more than one gram of ascorbic acid did not result in oxalate deposit formation in the subjects. Another recent study on 45,619 men for 14 years had given a conflicting report that there is 41% higher risk in people consuming more than one gram of vitamin C in developing oxalate stones.
However this study had also concluded that persons consuming less than 250 mg/ day of ascorbic acid were also under high risk. The acidic vitamin C in urine may bind to calcium and reduce its availability for getting bound to oxalate. The possibility of deficiency of vitamin B6 and magnesium rather than the excess of ascorbic acid for the formation of calculi must be probed.
Though we may not fear for the risk of oxalate stones on high dose ascorbic acid consumption, it is prudent to evaluate the status of the individual prone to oxalate deposits and its recurrence, before embarking on high-dose vitamin C consumption. A person prone to calculi may also avoid excessive use of oxalate rich spinach, chocolate and rhubarb.
Vitamin C in the role of removing other types of kidney stones
Vitamin C has a diuretic action when consumed in high doses and this helps in flushing out the possible deposits, including calcium oxalate. Many calcium oxalate and other deposits usually form around a nucleus of infection. Ascorbic acid due to its pH lowering action, appears to retard, kill and flush out the causative agents like bacteria and nanobacteria.Calcium phosphate stones, unlike calcium oxalate stones are alkaline in nature and get dissolved by the ascorbic acid in the urine. Struvite kidney stones ( formed by magnesium ammonium phosphate) also differ in nature and are easily soluble in urine due to high ascorbic acid.
Vitamin C depletion due to maintenance hemodialysis in kidney impaired patients
In maintenance hemodialysis, the water soluble ascorbic acid is depleted. The food intake of ascorbic acid must be monitored, so as avoid development of deficiency. If necessary supplements in regulated doses must be given.Doses in excess of 100-200 mg must be avoided in chronic renal disease as oxalates can accumulate in the body causing oxalosis. This can even cause acute renal failure. Oxalosis due to excess vitamin C in kidney transplant recipients can affect renal transplants and cause graft failure.
Vitamin C and oxalate stones in kidney
Vitamin C fruits - Richest sources
Vitamin C is abundantly available in plant sources like fruits and vegetables
Kakadu plums - rich sources of vitamin C (3100 mg/100 gm)
Kakadu plums (Terminalia ferdinandiana) are the richest known sources of ascorbic acid.
These kakadu plum trees are medium sized and are tropical and native to Australia.
Kakadu plums are about 2 cm long and are almond-like.
Kakadu plums are green-yellow colored and have one large seed.
Kakadu plums have been found to contain even up to 5% ascorbic acid per plum by weight.
Camu Camu - rich in vitamin C (2800 mg/100 gm)
Camu camu (Myrciaria dubia) are the second richest sources of ascorbic acid containing up to 3000 mg per 100 gm.
Camu camu is a bushy tree found in the Amazon rain forests along the river side. Camu camu fruits are small, red and cherry like.
Camu camu gives high acidic taste and is consumed mixed with other food or diluents.
The processed powder of camu camu pulp has hit the market and it may start replacing synthetic sources of ascorbic acid.
Rose hips - rich in vitamin C (2000 mg/100 gm)
Rose hips are the fruits of the rose plant and they are orange-red in colour.
Rose hips are very rich, containing up to 2000 mg per 100 gm.
Rose hips of the species Rosa canina and R. majalis are particularly rich in vitamin C.
These bushy plants are also used as ornamental plants. Rose hips are used in the preparation of herbal tea.
Rose hips are also used in food preparations like jam. Rose hips also contain antioxidant flavonoids and essential fatty acids.
Acerola - rich in vitamin C (1600 mg/100 gm)
Acerola (Malpighia glabra) are small trees, bearing fruits with the appearance of cherry.
Acerola trees are found in the southern region of North America and South America.
Acerola is presently cultivated throughout the world. Acerola are small 1-3 cm drupes bright red in color.
Acerola are near acidic in taste with three seeds. Acerola contains up to 1600 mg of ascorbic acid per 100 gm.
Sea Buckthorn fruits - rich sources of vitamin C (700 mg/100 gm)
Seabuckthorn (Hippophae rhamnoides) are shrubs widespread in Asia and Europe.
The orange coloured berries contain 700 mg of vitamin C per 100 gm. The berries are acidic in nature.
Jujube fruits - rich sources of vitamin C (500 mg/100 gm)
Jujube or red date or Chinese date are the drupe fruits of the jujube shrubs (Ziziphus zizyphus). Jujube shrubs are widespread in Asia and have been introduced in Europe.
Jujube are eaten fresh or with sugar syrup. Jujube contains nearly 500 mg of ascorbic acid per 100 gm of fruits.
In Asia, jujube has a role in the cultural functions and traditional medicine.
Vitamin C in Indian gooseberry (450 mg/100 gm)
Indian gooseberry (Phyllanthus emblica) is a deciduous medium sized tree.
The Indian gooseberry are berries which are greenish yellow in color, round and hard.
Indian gooseberry is sour, astringent and bitter in taste.
Indian gooseberry is consumed raw or used in food preparations.
Indian gooseberry has been used in Indian traditional medicine for thousand years.
Indian gooseberry contains up to 500 mg of vitamin C per 100 gm of fruits.
Indian gooseberry also contains high levels of other antioxidants.
Vitamin C in Baobab fruits (400 mg/100 gm)
Baobab (Adansonia sp.) are found in Africa, Australia and Madagascar.
Baobab trees store water inside their trunk. Baobab fruits are nutritious containing up to 400 mg of vitamin C per 100 gm.
The dried pulp of baobab is eaten raw as well as used in various preparations. In certain parts of Africa juice of baobab is used.
Vitamin C in Blackcurrant (200 mg/100 gm)
Blackcurrant (Ribes nigrum) is small shrub growing in northern Asia and North and central Europe.
Blackcurrant fruits are rich in ascorbic acid, containing up to 200 mg per 100 gm.
Blackcurrant is a berry which is dark purple to black in color, measuring 1 cm in diameter.
Blackcurrant having sweet taste is used in a number of food preparations like salads, jams, jellies and syrups.
Vitamin C in Guava (100 mg/100 gm)
Guava (Psidium sp.) trees are native to Southeast Asia, Mexico, Central America and northern South America.
Guava trees are quite hardy and adaptable to colder regions.
Guava is eaten raw or used in food preparations like jam and salads.
Guava is rich in vitamin C and contains 100 mg per 100 gm.
Richest fruit sources of vitamin C.
Vitamin C antioxidant function
Home > Vitamin C as antioxidant
Vitamin C is one the potent antioxidant nutrient. Its water soluble property enhances its uses.
Antioxidant and its activity
Ascorbic acid as an antioxidant neutralizes and stops oxidative reactions caused by free radicals in our body.Vitamin C has a reactive reducing ion available and combines readily with the extra oxygen ion in the free radical, to form water and harmless products.
Free radical activity
During the biological process of metabolism and energy production a number of free radicals (reactive oxygen species) are generated in the body which are useful, in small quantities, for further biological activities.If these reactive oxygen species are in excess they can cause oxidative damages to body cells and kill them.
Due to our present food habits, sun exposure, pollution and the lifestyle, free radicals are being produced in our body in excess.
This is resulting in oxidative stress which is the precursor to all ailments of the body.
Vitamin C (ascorbic acid) antioxidant functions
- Ascorbic acid in aqueous solution, with the reactive hydrogen ion available, acts as reducing agent and neutralises the free radicals before they reach the cells and damage them.
- When the free reactive oxygen species (such as superoxide and hydroxyl radicals) formed in the body seek out an electron to gain stability vitamin C in the water soluble form readily reacts with them forming harmless by-products.
- Further inside the cells ascorbic acid as an reducing agent prevents the damage to lipids, cell membrane and the cell contents.
- Glutathione peroxidase, with the association of vitamin C helps in the re-synthesis of vitamin E which is fat soluble.
- Working along with vitamin E (fat soluble) and glutathione peroxidase enzyme, ascorbic acid stops damage to lipids and also alteration and mutation of genetic materials like chromosomes.
- Vitamin C inhibits the production of nitrosamines from the nitrites prevalent in our present day foods. Nitrosamines are carcinogenic in nature.
- Ascorbic acid protects cell DNA from the oxidative damages caused by carcinogens, mutagens and free radicals.
- Vitamin C (ascorbic acid) has been found to reduce the oxidative damages of lungs from free radicals.
- Vitamin C reduces chromosomal abnormalities caused by coal tar, halogenated ethers, methyl methacrylate and styrene.
- LDL cholesterol is protected from being oxidized by free radicals by vitamin c antioxidant.
- Smokers are prone to LDL cholesterol oxidation and in trials it has been found that ascorbic acid as an antioxidant prevents the oxidative damages.
- Sodium, calcium and potassium salts of ascorbic acid are useful as food additives to protect it from oxidative damages.
- In sportsmen after a burst of activity or exercise the free radicals go up alarmingly causing fatigue due to muscle damage. Sufficient vitamin C (ascorbic acid) antioxidant present in the body lowers the muscle damage and fatigue.
Vitamin C (ascorbic acid)
Vitamin C - Foods - Sources
Nutrition
Deficiency and Therapy
Collagen
Current topic:
Antioxidant function of vitamin C
Vitamin C in collagen synthesis
Vitamin C (ascorbic acid) is required for collagen synthesis, a vital protein component of connective tissue.
Type 1: This is for the formation of skin, organs, bone matrix, ligaments, tendons and blood vessels.
Type 2: This is for the formation of cartilage.
Type 3: This is for the formation of the reticular fibres.
Type 4: This is for the formation of Cell basement membrane.
Type 5: this is for the formation of Cell surfaces, placenta and hair.
Vitamin C deficiency affects the assembly, secretion, or other biological processes involved in the production of this vital protein.
Vitamin C in Collagen synthesis
Collagen has unique amino acid composition depending upon the type of tissue formed. Amino acid Glycine (Gly) is found at almost every third place and amino acids Proline (Pro) and its derivative Hydroxyproline makes up about 10% of this protein. Proline and hydroxyproline play key role in the stability of this protein by helping the twist of helix.In the higher organisms like humans, for maintaining the connective tissue, critical and crucial biochemical process is hydroxylation of proline.
Its synthesis for increasing its conformational stability significantly, hydroxylation of the amino acid proline by the enzyme prolyl hydroxylase is required.
Ascorbic acid is a necessary cofactor in this biochemical process.
Vitamin C (ascorbic acid) and enzyme catalysed reactions occurs in the lumen present in the endoplasmic reticulum.
Lack of this ascorbic acid (ascorbate) cofactor results in defects in this hydroxylation and mutations in the enzyme prolyl hydroxylase affecting the protein and its proper formation.
Vitamin C in collagen synthesis process more than serving as catalyst gets destroyed by donating H atom in the critical process of assembling this protein in the tissues.
Collagen synthesis and vitamin C.
Vitamin C (ascorbic acid) - properties - synthesis - production
Ascorbic acid (vitamin C) is an essential organic compound required for umpteen biosynthetic activities in most of the animals and all humans.
Ascorbic acid, the official name of vitamin C, was first discovered in 1912.
In 1933 it was isolated for the first time in lemons.
It appears as white or light yellow crystals or powder. Its empirical formula is C6H8O6.
It is made up of elements carbon, hydrogen and oxygen.
It is water soluble. In alcohol it dissolves sparingly.
In benzene, ether and chloroform it is insoluble.
It is also known as L-ascorbate. Its chemical name is L-ascorbic acid.
At the temperature of 190-192 degree Celsius it decomposes.
Its bioavailability is rapid and complete. It binds negligibly with proteins.
Its metabolic half life is 30 minutes. It is excreted by the kidneys.
Biosynthesis of vitamin C in animals and the human inability
It is biosynthesized by reptiles and birds (older orders) in their kidneys. Birds of recent orders and most of the mammals synthesize it in their livers.
It is water soluble. In alcohol it dissolves sparingly.
In benzene, ether and chloroform it is insoluble.
It is also known as L-ascorbate. Its chemical name is L-ascorbic acid.
At the temperature of 190-192 degree Celsius it decomposes.
Its bioavailability is rapid and complete. It binds negligibly with proteins.
Its metabolic half life is 30 minutes. It is excreted by the kidneys.
Biosynthesis of vitamin C in animals and the human inability
It is biosynthesized by reptiles and birds (older orders) in their kidneys. Birds of recent orders and most of the mammals synthesize it in their livers.
In these animals glucose is converted into ascorbic acid with the help of the enzyme L-gulonolactone oxidase.
In most of these animals ascorbic acid is a natural metabolite of liver.
Humans, most of the primates and guinea pigs cannot produce vitamin C in the body and they are required to source it from their food and can develop its deficiency.
In most of these animals ascorbic acid is a natural metabolite of liver.
Humans, most of the primates and guinea pigs cannot produce vitamin C in the body and they are required to source it from their food and can develop its deficiency.
It is hypothesized that humans and primates, by a genetic mutation, must have lost their capacity to synthesize L-gulonolactone oxidase long ago due to which they are unable to produce ascorbic acid.
This being a vital nutrient for the biosynthetic activities, is included as 'vitamin C' among essential nutrients.
The pharmacophore (the molecular frame required for the biological activity) of ascorbic acid to function in the biological activities is ascorbate ion.
L-ascorbate, which is related to glucose in structure, occurs naturally attached to hydrogen forming ascorbic acid.
Alternatively it may occur attached to metal ion forming its ascorbate.
This ascorbate ion is highly reactive and scavenging free radicals, functions as antioxidant.
Absorption, transport and excretion of ascorbic acid
Vitamin C is absorbed into the body by simple diffusion and active transport by SVCTS (Sodium-Ascorbate Co-Transporters) and GLUTS (Hexose transporters).
In normal regular intake absorption is 75-90%.
In heavy doses the absorption rate may fall down to 15%.
There is a renal reabsorption threshold and any concentration above this is excreted through urine.
Though there is a blood threshold for renal reabsorption, many tissues in the body maintain higher concentrations of it.
Adrenal glands, pituitary gland, corpus luteum, thymus and retina accumulate vitamin C as high as 100 times the concentration in blood.
The excess of vitamin C which is not yet excreted is oxidised and broken down by the body by the activity of the enzyme L-ascorbate oxidase.
This being a vital nutrient for the biosynthetic activities, is included as 'vitamin C' among essential nutrients.
The pharmacophore (the molecular frame required for the biological activity) of ascorbic acid to function in the biological activities is ascorbate ion.
L-ascorbate, which is related to glucose in structure, occurs naturally attached to hydrogen forming ascorbic acid.
Alternatively it may occur attached to metal ion forming its ascorbate.
This ascorbate ion is highly reactive and scavenging free radicals, functions as antioxidant.
Absorption, transport and excretion of ascorbic acid
Vitamin C is absorbed into the body by simple diffusion and active transport by SVCTS (Sodium-Ascorbate Co-Transporters) and GLUTS (Hexose transporters).
In normal regular intake absorption is 75-90%.
In heavy doses the absorption rate may fall down to 15%.
There is a renal reabsorption threshold and any concentration above this is excreted through urine.
Though there is a blood threshold for renal reabsorption, many tissues in the body maintain higher concentrations of it.
Adrenal glands, pituitary gland, corpus luteum, thymus and retina accumulate vitamin C as high as 100 times the concentration in blood.
The excess of vitamin C which is not yet excreted is oxidised and broken down by the body by the activity of the enzyme L-ascorbate oxidase.
Commercial production of Ascorbic acid
Earlier vitamin C has been made commercially by extracting it from plants.
Later vitamin C was chemically synthesized. Presently it is being made by two processes.
Reichstein processEarlier vitamin C has been made commercially by extracting it from plants.
Later vitamin C was chemically synthesized. Presently it is being made by two processes.
In the Reichstein process, which is traditional and earlier, glucose is converted into sorbitol by heat treatment.
Sorbitol is fermented and oxidised (by a microorganism) to form sorbose.
This is made to react with acetone to produce di-acetone sorbose and further oxidised to produce DAKS (di-acetone keto gulonic acid).
Then by dissolving it in a mixture organic solvents the structure of DAKS is rearranged with the help of a catalyst to form vitamin C.
In the next step, by recrystallization vitamin C is purified.
Glucose by heat treatment --> Sorbitol by fermentation --> sorbose by chemical process --> Diacetone sorbose by chemical process --> DAKS by chemical process --> raw vitamin C by recrystallisation --> purified vitamin C
two-step fermentation process
In the two stage fermentation process developed in China, a second stage fermentation of sorbose produces KGA and this like DAKS by the same chemical process is converted into crude vitamin C and then purified.
The later process is cost effective and more realisation of ascorbic acid is achieved.
Much of the world supplies of vitamin C are from China. glucose by heat treatment --> sorbitol by fermentation --> sorbose by fermentation --> KGA by chemical process --> raw vitamin C by recrystallisation --> purified vitamin C
Other uses of ascorbic acidMuch of the world supplies of vitamin C are from China. glucose by heat treatment --> sorbitol by fermentation --> sorbose by fermentation --> KGA by chemical process --> raw vitamin C by recrystallisation --> purified vitamin C
Calcium, potassium and sodium salts of ascorbic acid are used as food additives for their antioxidant properties.
Ascorbyl stearate or ascorbyl palmitate, which are fat soluble esters of ascorbic acid, are used for protecting fatty food from oxidation.
It is used for enhancing the fermentation process in food preparation. It is also used in chemical processes as reducing agent. Vitamin C (ascorbic acid) is used to fix and keep the red colour of meat products.
Current topic:
Properties of vitamin C and its production and synthesis.
Function of vitamin C in human physiology
Home > Functions of vitamin C
Function of vitamin C in our body includes many vital metabolic activities like protein synthesis, energy production, antioxidative actions and neurotransmission.
Vitamin C being a very essential nutrient has important functions almost in all systems of the body. Some of the functions are briefly listed.
Function of vitamin C in the enzymatic reactions for collagen production
Vitamin C acts as an electron donor in many different enzymatic reactions taking place in various organs of our body.
It is a co-factor in lysyl hydroxylase and prolyl hydroxylase, the enzymes essential for collagen hydroxylation.
This hydroxylation of collagen is essential for its role in the developing and maintaining cartilage, blood vessels and scar tissue.
The function of vitamin C in energy production
The role of ascorbic acid in the enzymatic reactions for the production of carnitine is crucial.
Carnitine is biosynthesized from amino acid methionine and amino acid lysine.
Carnitine is required for transporting fatty acids from cytosol or intracellular fluid into mitochondria, (powerhouse of the cell) for the generation ATP and metabolic energy by the breakdown of lipids.
The role of vitamin C in neuro-transmission
The role of ascorbic acid in the enzymatic reaction of dopamine beta hydroxylase is in the biosynthesis of stress hormone norepinephrine (also a neurotransmitter) from dopamine.
This hormone along with epinephrine (another hormone and neurotransmitter) induces the brain for flight-fight response.
In another enzymatic reaction the role of ascorbic acid is in regulation of tyrosine (an amino acid) metabolism.
Tyrosine is a precursor of dopamine which in turn is a precursor for neurotransmitters.
The function of vitamin C in hormone production
In another enzymatic reaction with the association of ascorbic acid, amide groups are added to peptide hormones to increase their stability.
Some of the peptide hormones like luteinizing hormone, follicle-stimulating hormone, prolactin, adrenocorticotropic hormone (ACTH), growth hormone and antidiuretic hormone are very important for reproductive health, excretory organs, hormone production and regulation.
Vitamin C in immune reactions
One of the important role of vitamin c is in the production of certain antibodies essential for neutralising proteins of pathogens and give faster recovery from diseases.
Ascorbic acid helps in the production of interferon which gives resistance to the body for countering viral attacks.
Ascorbic acid counters the allergic reactions by interfering in the release of histamines and reducing histamine levels in blood circulation.
Nitrosamines are potential carcinogenic compounds. They are produced from nitrites found in food. These can cause cancer in the digestive system and their formation is blocked by vitamin C in the stomach.
Function of vitamin C in nutrition
Folic acid has to be converted into active form for proper utilisation and ascorbic acid aids in this metabolism of folic acid.
Iron has to be in oxidized form for absorption and utilisation by the body and in the presence of vitamin C this is achieved.
Vitamin E is regenerated from its reduced form by ascorbic acid.
Ascorbic acid functions as a regulator of serum levels of copper, iron and lead keeping them below toxic levels by stimulating their excretion, decreasing their absorption or increasing their absorption as required.
Function of vitamin C as antioxidant
The antioxidant activity of ascorbic acid prevents the oxidation of LDL (low density lipoprotein), oxidative damage of DNA and proteins.
Related topics:
Vitamin C (ascorbic acid)
Benefits
Too much - Over dose
Toxicity
Side effects
Foods - Sources
Current topic:
Functions of vitamin C
Related topics:
Vitamin C (ascorbic acid)
Benefits
Too much - Over dose
Toxicity
Side effects
Foods - Sources
Current topic:
Functions of vitamin C
Vitamin C - ascorbic acid - health benefits - uses
The benefits and uses of vitamin C in the maintenance of the healthy body are numerous.
Vitamin C health benefits and uses as antioxidant
Our body's metabolic reactions and energy production causes free radicals to be produced.
These free radicals, though have their requirement for our health, in excess, cause oxidative damages to our body cells and their death.
Ascorbic acid is a potent antioxidant and it neutralizes the free radicals and saves our body and health from these damages.
Health benefits and uses in the treatment and prevention of scurvy disease
Scurvy is a debilitating and life threatening disease caused by the deficiency of ascorbic acid.
100-120 mg of ascorbic acid is the daily requirement to ward off scurvy and improve health.
Daily consumption of citrus fruits keeps this disease at bay.
Vitamin C health benefits and uses in collagen production and wound healing
Collagen is a body connective tissue and fiber found in various parts of the body.
As connective tissue beneath the skin, it gives the skin elasticity.
Vitamin C forms the matrix for the calcium and phosphate deposition and the formation of bone tissue.
It is also required for connecting bones, cartilages and the tendons.
Collagen has important role in wound healing. For the formation of collagen ascorbic acid is very essential.
Health benefits and uses in cellular immune functions and in enhancing immunity
Vitamin c influences the immune system and helps in its fight against bacteria, viruses and other pathogens.
It is shown to stimulate production and function of white blood corpuscles (leukocytes).
It is also found to increase the production of antibodies.
It can also control the production of histamine and allergy.
Vitamin C health benefits and uses during the treatment of diseases and in their prevention
Coronary heart disease: regular dietary intake has been proved to decrease the risk of coronary heart disease.
Cardiovascular disease: as ascorbic acid is vasodilatory in function the incidence of cardiovascular diseases has been greatly reduced with the regular vitamin C intake.
Hypertension: regular supplementation with ascorbic acid reduces hypertension.
Stroke: it has been found that in persons with higher levels of serum vitamin C the risk of stroke is greatly reduced.
Cancer: there is marked improvement in the health of cancer patients with higher vitamin C intake and also protection to the users from cancer of gastrointestinal system and respiratory system.
Cataracts: The levels of vitamin C in the eye lens is found to decrease with age. Regular consumption of vitamin C reduces the risk of cataract.
Gout: Studies have shown that higher serum levels of uric acid causes gout. With regular consumption of vitamin C the serum levels of uric acid gets reduced.
Diabetes: regular intake of vitamin C, reduces the cardiovascular disease in the diabetes patients.
Vitamin C benefits and uses in medication and side effects
There is an increase in the requirement of vitamin C during the medication with antibiotics.
Benefits and uses in hormone production and body metabolism
Vitamin C helps in the production of hormones like thyroid.
Vitamin C regulates the adrenal glands and the production of stress hormones epinephrine and norepinephrine.
One of the health benefits and uses is in the metabolism of tryptophan, tyrosine and folates.
Benefits and uses for smokers, alcoholics, obese persons and workers in toxic environment
The body systems of alcoholics, smokers and persons living in toxic environment are always under stress. Their bodies utilizes more ascorbic acid to counter the stress.
Regular supplementation improves the health and benefits and protects them from faster deterioration of their conditions.
Uses in skin care, wrinkles and ageing
Skin aging and wrinkle formation are associated with oxidative activities due to exposure to elements (especially sun) and food habits.
It has been clinically proved that ascorbic acid slows the aging process.
Vitamin C health benefits and uses in the absorption of essential minerals and protection from harmful elements
For the absorption and use of iron in the human body ascorbic acid is very essential.
To tide over the ill effects of toxins like DDT and the heavy metals like mercury, cadmium and lead higher quantities of vitamin C is required.
Health benefits of vitamin C
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