carotene

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carotene

 [kar´o-tēn]
a yellow or red pigment found in many dark green, leafy, and yellow vegetables such as collards, turnips, carrots, sweet potatoes, and squash, as well as in yellow fruit, milk, egg yolk, and body fat; it is a chromolipoid hydrocarbon existing in four forms (α-, β-, γ-, and δ-carotene), which can be converted into vitamin A in the body.
beta carotene
1. the β isomer of carotene.
2. a preparation of this substance administered orally to prevent vitamin A deficiency and to reduce photosensitivity in patients with erythropoietic protoporphyria. Written also betacarotene and β-carotene.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

car·o·tene

(kar'ō-tēn),
A member of a class of carotenoids, yellow-red pigments (lipochromes) widely distributed in plants and animals, notably in carrots, and closely related in structure to the xanthophylls and lycopenes and to the open-chain squalene; of particular interest in that they include precursors of the vitamins A (provitamin A carotenoids). Chemically, they consist of 8 isoprene units in a symmetric chain with the 2 isoprenes at each end cyclized, forming either α-carotene or β-carotene (γ-carotene has only one end cyclized). The cyclic ends of β-carotene are identical β-ioninelike structures; thus, on oxidative fission, β-carotene yields 2 molecules of vitamin A. The cyclic ends of α-carotene differ in that one is an α-ionone and the other a β-ionone; on fission, α-carotene, like γ-carotene, yields 1 molecule of vitamin A (a β-ionone derivative).
Farlex Partner Medical Dictionary © Farlex 2012

carotene

(kăr′ə-tēn′) also

carotin

(-tĭn)
n.
An orange-yellow to red crystalline pigment, C40H56, found in animal tissue and certain plants, such as carrots and squash. It exists in several isomeric forms and is converted to vitamin A in the liver.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

car·o·tene

(kar'ō-tēn)
Yellow-red pigments (lipochromes) widely distributed in plants and animals, notably in carrots, and closely related in structure to the xanthophylls and lycopenes and to the open-chain squalene; they include precursors of vitamin A (provitamin A carotenoids).
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

carotene

One of a group of orange pigments found in carrots and some other vegetables. Beta-carotene (provitamin A) is converted to vitamin A in the liver. This vitamin is needed for normal growth and development of bone and skin, for the development of the fetus and for the proper functioning of the RETINA.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

carotene

an orange plant pigment of the CAROTENOID group which is usually present in the CHLOROPLASTS, and sometimes occurs in pigment-containing structures called CHROMOPLASTS which are found in yellow/orange leaves, vegetables and fruits. Carotene is also found in green leaves but the colour is masked; the orange colour can be seen in autumn leaves as the chlorophylls break down first. Carotene is necessary for the production of vitamin A in man and has an ABSORPTION SPECTRUM of about 450 nm. Carotene acts as an accessory pigment, passing energy to chlorophyll a for use in LIGHT REACTIONS and protecting chlorophyll from excessive light, and from oxidation by the oxygen produced in PHOTOSYNTHESIS.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

car·o·tene

(kar'ō-tēn)
Yellow-red pigments widely distributed in plants and animals, notably in carrots; include precursors of vitamin A.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
The [beta]-carotene was the predominant carotenoid (16.1 [micro]g.[g.sup.-1]), followed by phytoene, poly-cis-[gamma]-carotene, phytofluene, [gamma]-carotene and small levels of not identified carotene, [alpha]-cryptoxanthin (or zeinoxanthin) and [zeta]-carotene (Table 2).
This value is quite similar to the ones found in conventionally consumed fruits rich in provitamin A carotene, such as mango (35-215 RAE.100[g.sup.-1]) and acerola (35-325 RAE.100[g.sup.-1]) (RODRIGUEZ-AMAYA et al., 2008b).
"It might come as a surprise to most people," says Burri, "that even beta carotene, perhaps the best known of the carotenes, doesn't have its own RDA, or Recommended Dietary Allowance.
To find more about the interrelation of carotenes and vitamin A, Burri conducted two experiments, each with about a dozen healthy women aged 18 to 42.
She explains, "If the only acknowledged role of carotenes is to serve as precursors of vitamin A, then, in theory at least, if you have enough vitamin A, you don't need the carotenes."
Also, clinical trials can show whether it's beta-carotene, rather than something else in carotene-rich foods, that's preventing cancer (see "Don't Bother Counting the Carotenes").
A few dietary studies failed to find a link between carotene and cancer, but given the difficulty of getting accurate data on which foods have how much carotene and how often people eat how much of them, that comes as no surprise.
Beta-carotene is extensively used in providing color to foods and beverages, due to which, the segment is estimated to lead beta carotene market in the years to come.
Geographically, beta carotene industry is segmented as North America, Europe, Asia Pacific, and Middle East & Africa.
Control group C was given NIH laboratory diet, experimental group A was given toxic dose of acetaminophen 700 mg/kg body weight once daily and experimental group B was given beta carotene 30 mg/kg body weight once daily along with 700 mg/kg body weight acetaminophen once daily for one week.
Conclusion: It was concluded that beta carotene has hepatoprotective role on histomorphology of liver in acetaminophen-induced hepatotoxicity in rats.
[USPRwire, Thu Mar 07 2019] Rising use of carotene as a viable food additive is boosting the growth trajectory of carotene market.