Carotene
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Carotene is a terpene, an orange photosynthetic pigment, important for photosynthesis.
It is responsible for the orange colour of the carrot, and can cause people who have consumed enough to turn slightly yellow. It does not actively contribute in photosynthesis, but instead it transmits the energy it absorbs to chlorophyll.
Carotene is the dimer of vitamin A and comes in two forms α and β-carotene. Both types can be stored in the liver, and unlike vitamin A, excess carotene is non-toxic and can also be converted to vitamin A as needed.
α-carotene
Beta-carotene.png
Image:beta-carotene.png
β-carotene
β-carotene can be found in yellow, orange, and green leafy fruits and vegetables. These can be carrots, spinach, lettuce, tomatoes, sweet potatoes, broccoli, cantaloupe, and winter squash. As a rule of thumb, the greater the intensity of the color of the fruit or vegetable, the more beta-carotene it contains.
β-carotene is an anti-oxidant and such can be useful for curbing excess damaging free radicals in the body. However, the usefulness of β-carotene as a dietary supplement (i.e. taken as a pill) is still under debate. β-carotene is fat soluble so a small amount of fat is needed to adsorb it into the body.
External links
- Beta-carotene website by Martha Evens, School of Chemistry, University of Bristol (http://www.chm.bris.ac.uk/motm/carotene/beta-carotene_home.html)
- Berkeley Wellness Guide to Dietary Supplements (http://www.berkeleywellness.com/html/ds/dsBetaCarotene.php)
- Beta-caroten on University of Maryland (http://www.umm.edu/altmed/ConsSupplements/BetaCarotenecs.html)de:Carotine