vitamin
One of a group of organic substances, present in minute amounts in natural foodstuffs, that are essential to normal metabolism; insufficient amounts in the diet may cause deficiency diseases. [L. vita, life, + amine]
- v. A 1. any β-ionone derivative, except provitamin A carotenoids, possessing qualitatively the biological activity of retinol; deficiency interferes with the production and resynthesis of rhodopsin, thereby causing night blindness, and produces a keratinizing metaplasia of epithelial cells that may result in xerophthalmia, keratosis, susceptibility to infections, and retarded growth; 2. the original v. A, now known as retinol. SYN: axerophthol.
- v. A1 SYN: retinol.
- v. A2 SYN: dehydroretinol.
- v. A1 acid SYN: retinoic acid.
- v. A1 alcohol SYN: retinol.
- v. A aldehyde SYN: retinaldehyde.
- antiberiberi v. SYN: thiamin.
- antihemorrhagic v. SYN: v. K.
- antineuritic v. SYN: thiamin.
- antirachitic vitamins ergocalciferol (v. D2) and cholecalciferol (v. D3).
- antisterility v. SYN: v. E (2).
- v. B a group of water-soluble substances originally considered as one v..
- v. B1 SYN: thiamin.
- v. B2 1. SYN: riboflavin. 2. obsolete term for a complex of folic acid, nicotinic acid, nicotinamide, pantothenic acid, and riboflavin.
- v. B3 1. obsolete term for nicotinamide and/or nicotinic acid; 2. obsolete term for pantothenic acid.
- v. B4 1. once believed to be a factor necessary for nutrition of the chick, now identified simply as certain essential amino acid s and/or adenine; 2. obsolete term for adenine.
- v. B5 term once used to describe biologic activities now ascribed to pantothenic acid or nicotinic acid.
- v. B6 pyridoxine and related compounds (pyridoxal; pyridoxamine).
- v. B12 generic descriptor for compounds exhibiting the biological activity of cyanocobalamin (cyanocob(III)alamin); the antianemia factor of liver extract that contains cobalt, a cyano group, and corrin in a cobamide structure. Several substances with similar formulas and with the characteristic hematinic action have been isolated and designated: B12a, hydroxocobalamin; B12b, aquacobalamin; B12c, nitritocobalamin; B12r, cob(II)alamin; B12s, cob(I)alamin; B12III, factors A and V1a (cobyric acid) and pseudovitamin B12. Vitamins B12a and B12b are known to be tautomeric compounds; B12b has been obtained from cultures of Streptomyces aureofaciens; B12c has been obtained from cultures of Streptomyces griseus and is distinguishable from B12 by differences in its absorption spectrum. The physiologically active v. B12 coenzymes are methylcobalamin and deoxyadenosinecobalamin. A deficiency of v. B12 is often associated with certain methylmalonic aciduria s. SYN: animal protein factor, antianemic factor, antipernicious anemia factor (1), erythrocyte maturation factor, maturation factor, methylcobalamin.
- v. BT SYN: carnitine.
- v. Bx SYN: p-aminobenzoic acid.
- v. B complex a pharmaceutical term applied to drug products containing a mixture of the B vitamins, usually B1, B2, B3, B5, and B6.
- v. Bc conjugase an enzyme catalyzing the hydrolysis of the pteroylpolyglutamic acids to pteroylmonoglutamic acid, with consequent increase in v. activity; v. Bc is an obsolete term for folic acid.
- v. B12 with intrinsic factor concentrate a combination of v. B12 with suitable preparations of the mucosa of the stomach or intestine of domestic animals used for food by humans.
- v. C SYN: ascorbic acid.
- coagulation v. obsolete term for v. K.
- v. D generic descriptor for all steroids exhibiting the biologic activity of ergocalciferol or cholecalciferol, the antirachitic vitamins popularly called the “sun-ray vitamins.” They promote the proper utilization of calcium and phosphorus, thereby producing growth, together with proper bone and tooth formation, in young children; the sulfate, a water-soluble conjugate, is found in the aqueous phase of human milk; v. D1 is a 1:1 mixture of lumisterol and v. D2.
- v. D2 SYN: ergocalciferol.
- v. D3 SYN: cholecalciferol.
- v. E 1. SYN: α-tocopherol. 2. generic descriptor of tocol and tocotrienol derivatives possessing the biologic activity of α-tocopherol; contained in various oils (wheat germ, cotton seed, palm, rice) and whole grain cereals where it constitutes the nonsaponifiable fraction; also contained in animal tissue (liver, pancreas, heart) and lettuce; deficiency produces resorption or abortion in female rats and sterility in males. SYN: antisterility factor, antisterility v., fertility v..
- v. F term sometimes applied to the essential unsaturated fatty acid s, linoleic, linolenic, and arachidonic acid s.
- fat-soluble vitamins those vitamins, soluble in fat solvents (nonpolar solvents) and relatively insoluble in water, marked in chemical structure by the presence of large hydrocarbon moieties in the molecule; e.g., vitamins A, D, E, K.
- fertility v. SYN: v. E (2).
- v. G obsolete term for riboflavin.
- v. H SYN: biotin. [Ger, H for Haut, skin]
- v. K generic descriptor for compounds with the biologic activity of phylloquinone; fat-soluble, thermostable compounds found in alfalfa, hog liver, fish meal, and vegetable oils, essential for the formation of normal amounts of prothrombin. SYN: antihemorrhagic factor, antihemorrhagic v..
- v. K1, v. K1(20) SYN: phylloquinone.
- v. K2, v. K2(30) SYN: menaquinone-6.
- v. K3 SYN: menadione.
- v. K4 SYN: menadiol diacetate.
- v. K5 an antihemorrhagic v..
- v. K2(35) SYN: menaquinone-7.
- microbial v. a substance necessary for the growth of certain microorganisms, e.g., biotin, p-aminobenzoic acid.
- v. P a mixture of bioflavonoids extracted from plants (especially citrus fruits). It reduces the permeability and fragility of capillaries and is useful in the treatment of certain cases of purpura that are resistant to v. C therapy. SEE ALSO: hesperidin, quercetin, rutin. SYN: capillary permeability factor, citrin, permeability v..
- permeability v. SYN: v. P.
- v. PP SYN: nicotinic acid.
- v. U term given to a factor in fresh cabbage juice that encourages the healing of peptic ulcer, (3-amino-3-carboxypropyl)dimethylsulfonium chloride, a methionine derivative.

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vi·ta·min also vi·ta·mine 'vīt-ə-mən, Brit also 'vit- n any of various organic substances that are essential in minute quantities to the nutrition of most animals and some plants, act esp. as coenzymes and precursors of coenzymes in the regulation of metabolic processes but do not provide energy or serve as building units, and are present in natural foodstuffs or are sometimes produced within the body

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n.
any of a group of substances that are required, in very small amounts, for healthy growth and development: they cannot be synthesized by the body and are therefore essential constituents of the diet. Vitamins are divided into two groups, according to whether they are soluble in water or fat. The water-soluble group includes the vitamin B complex and vitamin C; the fat-soluble vitamins are vitamins A, D, E, and K. Lack of sufficient quantities of any of the vitamins in the diet results in specific vitamin deficiency diseases.

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vi·ta·min (viґtə-min) [L. vita life + amine] any of various unrelated organic substances that occur in many foods in small amounts and that are necessary in trace amounts for the normal metabolic functioning of the body. They may be water-soluble or fat-soluble.

Medical dictionary. 2011.

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  • Vitamin K — has also been used as a slang term for ketamine, an unrelated anaesthetic. Vitamin K1 (phylloquinone). Both forms of the vitamin contain a functional naphthoquinone ring and an aliphatic side chain. Phylloquinone has a phytyl side chain …   Wikipedia

  • Vitamin D — is a group of fat soluble prohormones, the two major forms of which are vitamin D2 (or ergocalciferol) and vitamin D3 (or cholecalciferol).cite web|url=http://dietary supplements.info.nih.gov/factsheets/vitamind.asp|title=Dietary Supplement Fact… …   Wikipedia

  • Vitamin A — Systematic (IUPAC) name (2E,4E,6E,8E) 3,7 Dimethyl …   Wikipedia

  • Vitamin B6 — is a water soluble vitamin. Pyridoxal phosphate (PLP) is the active form and is a cofactor in many reactions of amino acid metabolism, including transamination, deamination, and decarboxylation. PLP also is necessary for the enzymatic reaction… …   Wikipedia

  • Vitamin-B — ist eine Vitamin Gruppe, in der acht wasserlösliche Vitamine zusammengefasst sind, die alle als Vorstufen für Koenzyme dienen. Die Nummerierung ist nicht durchgehend, weil sich bei vielen Substanzen, die ursprünglich als Vitamine galten, der… …   Deutsch Wikipedia

  • Vitamin B — ist eine Vitamin Gruppe, in der acht Vitamine zusammengefasst sind, die alle als Vorstufen für Koenzyme dienen. Die Nummerierung ist nicht durchgehend, weil sich bei vielen Substanzen, die ursprünglich als Vitamine galten, der Vitamin Charakter… …   Deutsch Wikipedia

  • vitamin K — n. a fat soluble vitamin, synthesized constantly by intestinal bacteria in mammals and occurring in certain green vegetables, fish meal, etc., that promotes blood clotting and is required for the synthesis of prothrombin by the liver: the two… …   Universalium

  • Vitamin A — is retinol. Carotene compounds (found, for example, in egg yolk, butter and cream) are gradually converted by the body to vitamin A (retinol). A form of vitamin A called retinal is responsible for transmitting light sensation in the retina of the …   Medical dictionary

  • Vitamin B1 — is thiamine. Vitamin B1 acts as a coenzyme in the metabolism of the body. Deficiency of thiamine leads to beriberi, a disease of the heart and nervous system. The word vitamin was coined in 1911 by the Warsaw born biochemist Casimir Funk (1884… …   Medical dictionary

  • Vitamin de — Beschreibung Deutschlernerzeitschrift Verlag NP PRESS.DE Erstausgabe 2002 Erscheinungsweise …   Deutsch Wikipedia

  • vitamin de — Beschreibung Zeitschrift für junge Deutschlerner Verlag Verein vitamin de , NP PRESS.DE Erstausgabe 2002 …   Deutsch Wikipedia

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