carotenoids


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ca·rot·e·noids

(ka-rot'e-noydz),
Generic term for a class of carotenes and their oxygenated derivatives (xanthophylls) consisting of 8 isoprenoid units (thus, tetraterpenes) joined so that the orientation of these units is reversed at the center, placing the two central methyl groups in a 1,6 relationship in contrast to the 1,5 of the others. All carotenoids may be formally derived from the acyclic C40H56 structure known as lycopene, with its long central chain of conjugated double bonds by hydrogenation, dehydrogenation, oxidation, cyclization, or combinations of these. Included as carotenoids are some compounds arising from certain rearrangements or degradations of the carbon skeleton, but not retinol and related C20 compounds. The nine-carbon end groups may be acyclic with 1,2 and 5,6 double bonds or cyclohexanes with a single double bond at 5,6 or 5,4 or cyclopentanes or aryl groups; these are now designated by Greek letter prefixes preceding "carotene" (α and δ, which are used in the trivial names α-carotene and δ-carotene, are not used for that reason). Suffixes (for example, -oic acid, -oate, -al, -one, -ol) indicate certain oxygen-containing groups (for example, acid, ester, aldehyde, ketone, alcohol); all other substitutions appear as prefixes (for example, alkoxy-, epoxy-, hydro-). ). The configuration about all double bonds is trans unless cis and locant numbers appear. The prefix retro- is used to indicate a shift of one position of all single and double bonds; apo- indicates shortening of the molecule. Many carotenoids have anticancer activities.

ca·rot·e·noids

(kă-rot'ĕ-noydz)
Generic term for a class of carotenes and their oxygenated derivatives (xanthophylls).

carotenoids

A large group of yellow or orange pigments occurring in plants some of which have antioxidant properties. Some of the carotenoids are carotenes.

carotenoids

a group of yellow/orange pigments found in plants, animals and microorganisms, which includes CAROTENES (orange) and xanthophylls (yellow).

Carotenoids

Carotenoids are yellow to deep-red pigments.
Mentioned in: Vitamin A Deficiency

carotenoids (k·rˑ·te·noidz),

n.pl fat-soluble plant pigments whose functions include photosynthesis, providing bright coloration (red, orange, and yellow), and protecting from light and oxygen (antioxidants). In humans, carotenoids are useful as an-tioxidants (compounds which prevent tissue damage and degeneration). See also beta-carotene, lutein, and lycopene.
References in periodicals archive ?
But the green pulp of avocado contains an assortment of carotenoids that includes: (4)
15) Carotenoids lycopene and [beta]-carotene degrade more intensively than L and Z; this may explain why L and Z are selectively taken up by the retina as opposed to other carotenoids present within the blood serum.
Scientists said that the results of this study strengthen the current body of research on this topic and complements a previous study (2) conducted in my lab that showed a similar enhancement in carotenoid absorption with one-half of an avocado.
In brief, the carotenoids were extracted by adding in hexane and distilled water to the pooled supernatant.
As mentioned, the carotenoid market has a lot of scope in medical field due to its newly discovered health benefits.
We identified the carotenoids in oriole feathers initially by analytical thin-layer chromatography (TLC) on flexible sheets of silica gel (PE SIL G; Whatman Ltd.
They added that the relationship between optimism and carotenoid levels was only partially explained by the fact that more optimistic people tended to engage in healthier behaviors such as eating fruits and vegetables and avoiding cigarette smoking.
This is the first study of its kind to report a relationship between optimism and healthier levels of carotenoid concentrations," Boehm added.
In more than 3,000 participants, there were significant associations between blood levels of carotenoids and breast cancer risk.
A prior 2004 study from Iowa State University found that carotenoids were more bioavailable in full-fat dressings than in either low-fat or fat-free dressings.
Carotenoids are natural tetraterpenes (C40) which are produced by microorganisms, plants, and marine invertebrates.