L Ascorbic Acid Or L Ascorbate Vitamin C Biology Essay
Vitamin C, besides known as L-ascorbic acid or L-ascorbate, is a H2O soluble vitamin, intending it is non stored in the organic structure in big sums. The name “ ascorbic ” comes from its belongings of forestalling and bring arounding scorbutus, a vitamin C lack. As H2O soluble vitamins enter the organic structure, they are put to work instantly and any extra is eliminated from the organic structure via the piss. Because the organic structure is non able to hive away these vitamins, they must be invariably resupplied. ( Hickey, S. Roberts, H. 2005 ) Vitamin C is so critical to populating animals that about all mammals can utilize their ain cells to do it. Most mammals make ascorbic acid in their liver where the enzyme L-gulonolactone oxidase is required to change over glucose to ascorbic acid. ( Harris, JR 2007 ) Humans, gorillas, Pan troglodytess, chiropterans, guinea hogs and birds are some of the few animate beings that can non do vitamin C inside of their ain organic structures. Because these animate beings can non bring forth vitamin C, it must be obtained from a nutrient beginning or addendum. Worlds vary greatly in their vitamin C demand. It ‘s natural for one individual to necessitate 10 times every bit much vitamin C as another individual. A individual ‘s age and wellness position can dramatically alter his or her demand for vitamin C.
Beginning: Vitamin C is produced of course in fruits and veggies. Terminalia ferdinandiana or The Kakadu Plum has the highest known vitamin C concentration than any other nutrient beginning at 3200-5000mg/100g, compared with 50mg/100g for oranges. Other common beginnings of vitamin C are blackcurrant, ruddy Piper nigrums, Petroselinum crispum, strawberries and kiwi fruit. Vitamin C is sensitive to the visible radiation, air and heat. ( Mason, JB. 2007 ) The most vitamin C can be obtained if fruits and veggies are eaten natural or cooked lightly. About 25 % of the vitamin C in veggies can be lost merely by paling. This same grade of loss occurs in the freeze and unthawing of veggies and fruits. Cooking of veggies and fruits for longer periods of clip can ensue in a loss of over 50 % the entire vitamin C content. In animate beings Vitamin C is found largely in the liver and least in the musculus tissue. Since most of the meat consumed in the human diet is carnal musculus, it is an undependable beginning. ( Hartigan, K. 2008 )
Chemical Properties: Ascorbic acid is a of course happening compound. The IUPAC name for Ascorbic Acid is 2-oxo-L-threo-hexono-1,4- lactone-2,3-enediol. It has the molecular expression of C6H8O6 and appears as a white or light xanthous solid. ( Levine, M. 2001 ) As mentioned before vitamin C is really sensitive to even little warming, to the visible radiation, and to the action of oxidising agents and metal ions. Vitamin C is readily oxidized, particularly in aqueous solutions, by responding with atmospheric O and behaves as a two-electron giver. ( Harris, JR 2007 ) Ascorbic acid is active in many biological procedures ; it maintains prolyl hydroxylase in an active signifier by continuing its Fe atom in the decreased Fe2+ province and it keeps collagen in a sufficiently hydroxylated signifier forestalling skin lesions and blood-vessel breakability that are so outstanding in scorbutus.
Physiological Properties: Ascorbic Acid is a sugar acid with antioxidant belongingss. It helps to keep healthy collagen in the tegument, fix damaged tissue, promote healthy dentitions and castanetss, and hike the immune system. Ascorbate acts as a cut downing agent to change by reversal oxidization in aqueous solution. When there are more free groups ( reactive O species ) in the human organic structure than antioxidants, the status is called oxidative emphasis. Oxidative emphasis induced diseases encompass cardiovascular diseases, high blood pressure, chronic inflammatory diseases and diabetes. ( Carr, AC. Frei, B. 1999 ) Absorption of vitamin C is greater when several single doses of vitamin C, in measures less than one gm, are taken throughout the twenty-four hours instead than one big dosage. A high Fe concentration in the GI piece of land may do oxidative devastation and in bend impair consumption. Active conveyance is the chief mechanism of vitamin C distribution within the organic structure. Simple diffusion may happen in the oral cavity and tummy but histories for merely a really little per centum of consumption. In the plasma absorbed ascorbic and dehydroascorbate ( DHAA ) can either be transported freely or be bound to albumin. Ascorbate can besides travel into organic structure cells and tissues. ( Mason, JB. 2007 ) Vitamin C besides aids the metamorphosis of tyrosine, folic acid, and tryptophan. Tryptophan is converted in the presence of ascorbic acid to 5-hydroxytryptophan, which forms 5-hydroxytryptamine, an of import encephalon chemical. ( Hartigan, K. 2008 )
Vitamin C is stored throughout organic structure tissues and blood. Ascorbic acerb content of blood constituents, fluid and tissue varies widely on an single footing. Tissue concentrations exceed those found in the plasma by three to ten times. Tissues that shop norm degrees of vitamin C include the kidneys, encephalon, liver, lungs, and thyroid. The water-soluble belongingss of vitamin C prevent it from being stored in the adipose tissue of the organic structure. ( Carr, AC. Frei, B. 1999 )
Metabolic Role: Metabolites of vitamin C include dehydroascorbate ( DHAA ) , oxalic acid, 2-O-methyl ascorbate and 2-ketoascorbitol. ( Englard, S. Seifter, S. 1986 ) Dehydroascorbate is an oxidised signifier of ascorbic acid. Vitamin C does non go through from the blood watercourse into the encephalon. Even though the encephalon is one of the variety meats which contain the greatest concentration of vitamin C. Alternatively it is dehydroascorbate that is transported through the blood-brain barrier via GLUT1 transporters, and so converted to vitamin C. Oxalic acid is normally found within the works land. 2-0-methyl Ascorbate is a salt produced from ascorbic acid. ( Hartigan, K. 2008 )
Lack and Disease: Symptoms of a vitamin C lack include weak immune map, including susceptibleness to colds and other infections. The liner of the respiratory piece of land besides depend to a great extent on vitamin C for protection, respiratory infection and other lung-related conditions can besides be diagnostic of vitamin C lack. ( Groff, JL. Et. Al. 2002 ) Scurvy is a disease ensuing from the lack of vitamin C. Scurvy is characterized by swollen and hemorrhage gums with disentangled dentitions, tenderness and stiffness of the articulations and lower appendages, shed blooding under the tegument and in deep tissues, decelerate lesion healing, and anaemia. More terrible symptoms include psychotic upsets, black and bluish musca volitanss and broken capillaries. These occur shortly before decease. Scurvy is one of the attach toing diseases of malnutrition and therefore is still widespread in countries of the universe depending on external nutrient assistance. Though rare, there are besides documented instances of scorbutus due to hapless dietetic picks by people populating in industrialised states. ( Toss offing, C. Et Al. 2006 )
Toxicity: At high auxiliary doses affecting 5g or more of vitamin C a twenty-four hours, diarrhoea can ensue from the fluid in the bowel going excessively concentrated. Vitamin C can be transformed in the organic structure to oxalate, oxalic acidaa‚¬a„?s conjugate base, which is a common component of kidney rocks. Peoples who are prone to kidney rocks may desire to avoid big doses of the vitamin. Peoples who lack the control to modulate Fe consumption, such as sick persons of Haemochromatosis, should besides avoid big doses of the vitamin as it increases iron soaking up. Haemochromatosis is defined as an Fe overload with a hereditary/primary cause or arising from a metabolic upset.
Functions: Vitamin C serves a chiefly protective function in the organic structure. Cardiovascular diseases, some malignant neoplastic diseases, joint diseases and cataracts are associated with vitamin C lack. These could be partially prevented by an optimum consumption of vitamin C. Vitamin C achieves much of its protective consequence by working as an antioxidant and forestalling O based harm to cells in the organic structure. Structures that contain fat ( e.g. lipoprotein molecules which enable fats to be carried in the blood watercourse ) are peculiarly dependent on vitamin C for protection. For iron-deficiency anaemia, vitamin C helps the soaking up of Fe from the GI piece of land. ( Simon, H. Zieve, D. 2009 )
Bioavailability: Natural and man-made ascorbic acid are chemically indistinguishable. There appears to be no clinically important difference in the bioavailability and bioactivity of natural ascorbic acid and man-made ascorbic acid. The mean half life of ascorbic acid is believed to be between 16 and 20 yearss. Its half life is reciprocally related to intake. ( Englard, S. Seifter, S. 1986 ) The water-soluble belongingss of vitamin C lead to urinary elimination of the vitamin. The kidneys play a major function in vitamin C elimination and keeping. Levels within the organic structure that are 1500 milligram or less will ensue in no urinary elimination of vitamin C. Drugs which can consume the bodyaa‚¬a„?s supply of ascorbic acid include preventives like the pill, anti-inflammatory drugs such as acetylsalicylic acid, antibiotics and malignant neoplastic disease intervention drugs.
Fortification: Ascorbic acid is used widely in the nutrient industry for its nutritionary value and for the many functional parts it has to merchandise quality. Because ascorbic acid is an antioxidant, it helps to better the coloring material and palatableness of many nutrient merchandises. There are engineerings available for vitamin C munition of fruit juices, fruit juice drinks, other related drinks, dairy merchandises and some breakfast cereals. Some juices that are non usually a beginning of vitamin C can hold vitamin C added. Although vitamins in their purest signifier have small gustatory sensation, it is of import that the add-on of the vitamin to the merchandise does non alter its gustatory sensation. This could impact the sale of the merchandise. During the fabrication of fruit juices from fruits such as apples and Prunus persicas, ascorbic acid may be added during the suppression, striving or pressing procedures. This helps to forestall the enzymatic Browning of the natural fruits. Browning of fruits occurs when the polyphenolases, which are found in the tissue of fruits, catalyze the oxidization of phenols, besides of course present in the fruit, to organize quinones. The quinones can so polymerise to make melanins. Melanins are the compounds which cause the brown pigmentation. ( Vitamin C Foundation, 2009 )
Addendums: Dietary addendums typically contain vitamin C in the signifier of ascorbic acid. Because vitamin C is better absorbed in the presence of flavonoids, many addendum makers besides add flavonoids to their merchandises. Buffered versions of vitamin C are besides normally available. These buffered signifiers normally combine vitamin C with minerals like Ca, Mg or K. Buffered vitamin C may be helpful for persons who have stomach sensitiveness or who are taking higher doses of the addendum. Besides widely available is a complex signifier of vitamin C in which ascorbic acid is combined with several of its of course happening metabolites including dehydroascorbate, threonate and aldonic acids. ( Hamrick, I. Counts, SH. 2008 )
Decision: In decision vitamin C is a water-soluble vitamin that is necessary for normal growing and development. There are many medical benefits of holding a regular vitamin C consumption. The organic structure does non fabricate vitamin C on its ain, nor does it hive away it. It is hence of import to include plentifulness of vitamin C-containing nutrients in a day-to-day diet.
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