Beta Carotene
<h3 ><b >What is Beta-Carotene?</b></h3>
<p >Beta-carotene is one of a group of natural chemicals known as carotenes or carotenoids. Carotenes are responsible for the orange color of many fruits and vegetables such as carrots, pumpkins, and sweet potatoes.</p>
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Beta carotene is converted in the body to vitamin A. It is an antioxidant, like vitamins E and C.</p>
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<b>β-Carotene</b> is a strongly-coloured red-orange <a href="http://en.wikipedia.org/wiki/Pigment" title="Pigment" >pigment</a> abundant in plants and fruits. It is an<a href="http://en.wikipedia.org/wiki/Organic_compound" title="Organic compound" >organic compound</a> and chemically is classified as a <a href="http://en.wikipedia.org/wiki/Hydrocarbon" title="Hydrocarbon" >hydrocarbon</a> and specifically as a <a href="http://en.wikipedia.org/wiki/Terpenoid" title="Terpenoid" >terpenoid</a> (isoprenoid), reflecting its derivation from <a href="http://en.wikipedia.org/wiki/Isoprene" title="Isoprene" >isoprene</a> units. β-Carotene is biosynthesized from <a href="http://en.wikipedia.org/wiki/Geranylgeranyl_pyrophosphate" title="Geranylgeranyl pyrophosphate" >geranylgeranyl pyrophosphate</a>.
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<sup id="cite_ref-Kirk_2-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Beta-Carotene#cite_note-Kirk-2" >[3]</a></sup> It is a member of the <a href="http://en.wikipedia.org/wiki/Carotene" title="Carotene" >carotenes</a>, which are <a href="http://en.wikipedia.org/wiki/Tetraterpene" title="Tetraterpene" >tetraterpenes</a>, synthesized biochemically from eight isoprene units and thus having 40 carbons. Among this general class of carotenes, β-Carotene is distinguished by having <a href="http://en.wikipedia.org/wiki/Carotene" title="Carotene" >beta-rings</a> at both ends of the molecule. Absorption of β-Carotene is enhanced if eaten with fats, as carotenes are fat soluble.</p>
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Carotene is the substance in <a href="http://en.wikipedia.org/wiki/Carrots" title="Carrots" class="mw-redirect" >carrots</a> that colours them orange and is the most common form of carotene in plants. When used as a food colouring, it has the <a href="http://en.wikipedia.org/wiki/E_number" title="E number" >E number</a> E160a.<sup id="cite_ref-isbn0-471-73518-3_3-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Beta-Carotene#cite_note-isbn0-471-73518-3-3" >[4]</a></sup><sup >p119</sup> The structure was deduced by Karrer et al. in 1930.<sup id="cite_ref-4" class="reference" ><a href="http://en.wikipedia.org/wiki/Beta-Carotene#cite_note-4" >[5]</a></sup> In nature, β-carotene is a precursor (inactive form) to <a href="http://en.wikipedia.org/wiki/Vitamin_A" title="Vitamin A" >vitamin A</a> via the action of <a href="http://en.wikipedia.org/wiki/Beta-carotene_15,15%27-monooxygenase" title="Beta-carotene 15,15'-monooxygenase" >beta-carotene 15,15'-monooxygenase</a>.<sup id="cite_ref-Kirk_2-1" class="reference" ><a href="http://en.wikipedia.org/wiki/Beta-Carotene#cite_note-Kirk-2" >[3]</a></sup> Isolation of β-carotene from fruits abundant in carotenoids is commonly done using column <a href="http://en.wikipedia.org/wiki/Chromatography" title="Chromatography" >chromatography</a>. The separation of β-carotene from the mixture of other carotenoids is based on the polarity of a compound. β-Carotene is a non-polar compound, so it is separated with a non-polar solvent such as <a href="http://en.wikipedia.org/wiki/Hexane" title="Hexane" >hexane</a>.<sup id="cite_ref-5" class="reference" ><a href="http://en.wikipedia.org/wiki/Beta-Carotene#cite_note-5" >[6]</a></sup> Being highly <a href="http://en.wikipedia.org/wiki/Conjugated_system" title="Conjugated system" >conjugated</a>, it is deeply colored, and as a <a href="http://en.wikipedia.org/wiki/Hydrocarbon" title="Hydrocarbon" >hydrocarbon</a> lacking functional groups, it is very <a href="http://en.wikipedia.org/wiki/Lipophilic" title="Lipophilic" class="mw-redirect" >lipophilic</a>.</p>