Provitamin: Difference between revisions
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Created page with "{{Short description|Substances animals can metabolize into vitamins}} A '''provitamin''' is a substance that may be converted within the body to a vitamin. The term '''previtamin''' is a synonym. The term "provitamin" is used when it is desirable to label a substance with little or no vitamin activity, but which can be converted to an active form by normal metabolic processes. ==Example== Some provitamins are: * "Provitamin A" is a name for Beta-C..." |
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Some provitamins are: | Some provitamins are: | ||
* "Provitamin A" is a name for [[Beta-Carotene|β-carotene]], | * "Provitamin A" is a name for [[Beta-Carotene|β-carotene]], which has only about 1/6 the [[biological activity]] of [[retinol]] ([[vitamin A]]); the body uses an [[enzyme]] to convert β-carotene to retinol. In other contexts, both β-carotene and retinol are simply considered to be different forms ([[vitamer]]s) of vitamin A. | ||
* "Provitamin B5" is a name for [[panthenol]], which may be converted in the body to vitamin B<sub>5</sub> ([[pantothenic acid]]). | * "Provitamin B5" is a name for [[panthenol]], which may be converted in the body to vitamin B<sub>5</sub> ([[pantothenic acid]]). | ||
* [[Menadione]] is a synthetic provitamin of [[vitamin K]]. | * [[Menadione]] is a synthetic provitamin of [[vitamin K]]. | ||
Revision as of 15:56, 21 February 2024
A provitamin is a substance that may be converted within the body to a vitamin. The term previtamin is a synonym.
The term "provitamin" is used when it is desirable to label a substance with little or no vitamin activity, but which can be converted to an active form by normal metabolic processes.
Example
Some provitamins are:
- "Provitamin A" is a name for β-carotene, which has only about 1/6 the biological activity of retinol (vitamin A); the body uses an enzyme to convert β-carotene to retinol. In other contexts, both β-carotene and retinol are simply considered to be different forms (vitamers) of vitamin A.
- "Provitamin B5" is a name for panthenol, which may be converted in the body to vitamin B5 (pantothenic acid).
- Menadione is a synthetic provitamin of vitamin K.
- Provitamin D2 is ergosterol, and provitamin D3 is 7-dehydrocholesterol. They are converted by UV light into vitamin D.[1] The human body produces provitamin D3 naturally; deficiency is usually caused by a lack of sun exposure, not a lack of the provitamin.
External links
 | この記事は、クリエイティブ・コモンズ・表示・継承ライセンス3.0のもとで公表されたウィキペディアの項目Provitamin(5 December 2023編集記事参照)を素材として二次利用しています。 Item:Q21162  |
- ↑ Cite error: Invalid
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