ascorbic acid


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Related to ascorbic acid: citric acid

ascorbic acid:

see vitaminvitamin,
group of organic substances that are required in the diet of humans and animals for normal growth, maintenance of life, and normal reproduction. Vitamins act as catalysts; very often either the vitamins themselves are coenzymes, or they form integral parts of coenzymes.
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Ascorbic acid

A white, crystalline compound, also known as vitamin C. It is highly soluble in water, which is a stronger reducing agent than the hexose sugars, which it resembles chemically. Vitamin C deficiency in humans has been known for centuries as scurvy. The compound has the structural formula shown below.

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The stability of ascorbic acid decreases with increases in temperature and pH. This destruction by oxidation is a serious problem in that a considerable quantity of the vitamin C content of foods is lost during processing, storage, and preparation.

While vitamin C is widespread in plant materials, it is found sparingly in animal tissues. Of all the animals studied, only a few, including humans, require a dietary source of vitamin C. The other species are capable of synthesizing the vitamin in such tissues as liver and kidneys. Some drugs, particularly the terpene-like cyclic ketones, stimulate the production of ascorbic acid by rat tissues.

Vitamin C–deficient animals suffer from defects in their mesenchymal tissues. Their ability to manufacture collagen, dentine, and osteoid, the intercellular cement substances, is impaired. This may be related to a role of ascorbic acid in the forma- tion of hydroxy-proline, an amino acid found in structural proteins, particularly collagen. People with scurvy lose weight and are easily fatigued. Their bones are fragile, and their joints sore and swollen. Their gums are swollen and bloody, and in advanced stages their teeth fall out. They also develop internal and subcutaneous hemorrhages.

There is evidence that vitamin C may play roles in stress reactions, in infectious disease, or in wound healing. Therefore, many nutritionists believe that the human intake of ascorbic acid should be many times more than that intake level which produces deficiency symptoms. The recommended dietary allowances of the Food and Nutrition Board of the National Research Council are 30 mg per day for 1- to 3-month infants, 80 mg per day for growing boys and girls, and 100 mg per day for pregnant and lactating women. These values represent an intake which tends to maintain tissue and plasma concentrations in a range similar to that of other well-nourished species of animals. See Vitamin

ascorbic acid

[ə′skȯr·bik ′as·əd]
(biochemistry)
C6H8O6 A white, crystalline, water-soluble vitamin found in many plant materials, especially citrus fruit. Also known as vitamin C.

ascorbic acid

a white crystalline vitamin present in plants, esp citrus fruits, tomatoes, and green vegetables. A deficiency in the diet of man leads to scurvy. Formula: C6H8O6
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He intends to organize a multi-institution, placebo-controlled, phase II study of IV ascorbic acid in sepsis.
Result showed that, the effect of ascorbic acid was superior to both nicotinic acid and turmeric extract with regard to total carotenoids, especially at a concentration of 200 ppm, and on total flavonoids at the concentration of 100 ppm.
The addition of ascorbic acid and ascorbic acid plus AJNE into sausages let to a significant decrease (32.
Extrapolation from the standard curve shows that 50% DPPH Inhibition of ascorbic Acid was 0.
Until recently the mechanism of action was uncertain, although there is quite recent in vitro evidence (2008) that confirms the direct anti-viral activity of both ascorbic acid and dehydroascorbic acid (ascorbic acid in its reduced form) in defined conditions (10).
Their almost unlimited amount of ascorbic acid has given them enormous powers of survival.
Drying resulted in high loss of ascorbic acid, which was 60% when the vegetable was dried with salt and 85% without salt.
1995 Superoxide Dismutase (SOD) Misra and Fridovich (1972 ascorbic acid Roe and Keuther (1953 [alpha]--Tocopherol Rosenberg (1992).
Not to mention the fact that ascorbic acid and some B vitamins just do not get along with each other.
Mario Ferruzzi, lead researcher and associate professor of food science and nutrition at Purdue University, insists that adding ascorbic acid to green tea would increase the absorbability of catechins found in the tea.
China produces most of the world's ascorbic acid (E300-304), a preservative and antioxidant used in products from bread to crisps.