What Is It?
Carotene is probably the best known of the carotenoids those red orange and yellow pigments that give color to many fruits and vegetables. The body converts carotene into vitamin A a nutrient first identified in the 1930s and now recognized as vital to the growth and development of the human body.
As a potent immune-system booster and a powerful antioxidant--it counters the effects of cell-damaging molecules called free-radicals-- carotene has an important role to play in human health.
Consuming plenty of fruits and vegetables is an excellent way to supply your body with carotene. In addition carotene is now sold in supplement form.
Scientists have long hoped that supplements could provide concentrated sources of carotene and thus provide increased protection against heart disease and even against certain cancers. Recent findings however indicate that single high-dose carotene supplements may actually do more harm than good--possibly increasing (rather than decreasing) the number of cell-damaging free-radicals in the body.
Until more information is available it's probably wise to get carotene in supplement form only as part of a mixed complex along with other health-promoting carotenoids. Look for products that combine carotene with other carotenes such as alpha-carotene lycopene lutein zeaxanthin and cryptoxanthin.
The power and goodness of carrots Carrots have many important vitamins and minerals. They are rich in antioxidants Beta Carotene Alpha Carotene Phytochemicals and Glutathione Calcium and Potassium and vitamins A B1 B2 C and E which are also considered antioxidants protecting as well as nourishing the skin. They contain a form of calcium easily absorbed by the body. Finally they also contain Copper Iron Magnesium Manganese Phosphorous.and Sulphur - better than a wonder drug!
How to Take It
By far the best source of beta-carotene is fresh fruits and vegetables. Excellent sources include carrots cantaloupe and myriad other yellow orange and red fruits and vegetables. Green vegetables are also a good source. Choose dark ones such as broccoli romaine lettuce and spinach; the darker color indicates a higher beta-carotene content.
In terms of supplements the most effective and economical way to take beta-carotene is as part of a formula containing other significant health-promoting carotenoids such as alpha-carotene lycopene lutein zeaxanthin and cryptoxanthin. Many products supply these carotenoids in one pill.
Life presents us with a kaleidoscope of colors. From the green green grass of home to a forest's ruddy autumn hues we are surrounded by living color. Living things obtain their colors with few exceptions from natural pigments. In addition to their role in coloration natural pigments carry out a variety of important biological functions. Among the most common and most important natural pigments are the carotenoids.
Carotenoids are a class of natural fat-soluble pigments found principally in plants algae and photosynthetic bacteria where they play a critical role in the photosynthetic process. They also occur in some non-photosynthetic bacteria yeasts and molds where they may carry out a protective function against damage by light and oxygen. Although animals appear to be incapable of synthesizing carotenoids many animals incorporate carotenoids from their diet. Within animals carotenoids provide bright coloration serve as antioxidants and can be a source for vitamin A activity.Carotenoids are responsible for many of the red orange and yellow hues of plant leaves fruits and flowers as well as the colors of some birds insects fish and crustaceans. Some familiar examples of carotenoid coloration are the oranges of carrots and citrus fruits the reds of peppers and tomatoes and the pinks of flamingoes and salmon . Some 600 different carotenoids are known to occur naturally and new carotenoids continue to be identified .
Carotenoids are defined by their chemical structure. The majority carotenoids are derived from a 40-carbon polyene chain which could be considered the backbone of the molecule (Fig. 1). This chain may be terminated by cyclic end-groups (rings) and may be complemented with oxygen-containing functional groups. The hydrocarbon carotenoids are known as carotenes while oxygenated derivatives of these hydrocarbons are known as xanthophylls. Beta-carotene the principal carotenoid in carrots is a familiar carotene while lutein the major yellow pigment of marigold petals is a common xanthophyll (Fig. 1).
The structure of a carotenoid ultimately determines what potential biological function(s) that pigment may have. The distinctive pattern of alternating single and double bonds in the polyene backbone of carotenoids is what allows them to absorb excess energy from other molecules while the nature of the specific end groups on carotenoids may influence their polarity. The former may account for the antioxidant properties of biological carotenoids while the latter may explain the differences in the ways that individual carotenoids interact with biological membranes.
What do carotenoids do?
In human beings carotenoids can serve several important functions. The most widely studied and well-understood nutritional role for carotenoids is their provitamin A activity. Deficiency of vitamin A is a major cause of premature death in developing nations particularly among children. Vitamin A which has many vital systemic functions in humans can be produced within the body from certain carotenoids notably beta-carotene. Dietary beta-carotene is obtained from a number of fruits and vegetables such as carrots spinach peaches apricots and sweet potatoes. Other provitamin A carotenoids include alpha-carotene (found in carrots pumpkin and red and yellow peppers) and cryptoxanthin (from oranges tangerines peaches nectarines and papayas).
Carotenoids also play an important potential role in human health by acting as biological antioxidants protecting cells and tissues from the damaging effects of free radicals and singlet oxygen. Lycopene the hydrocarbon carotenoid that gives tomatoes their red color is particularly effective at quenching the destructive potential of singlet oxygen. Lutein and zeaxanthin xanthophylls found in corn and in leafy greens such as kale and spinach are believed to function as protective antioxidants in the macular region of the human retina. A xanthophyll found in salmon shrimp and other seafoods is another naturally occurring xanthophyll with potent antioxidant properties. Other health benefits of carotenoids that may be related to their antioxidative potential include enhancement of immune system function protection from sunburn and inhibition of the development of certain types of cancers.
Carotenoids are plant pigments that involve in light harvesting to participate in energy transfer process in photosynthesis. They absorb light in the 400-500 nm region of the visible spectrum and impart coloration of yellow orange red and purple. They are widely distributed in nature including vegetables fruits insects fishes and birds. Animals are incapable of synthesizing carotenoids which should be obtained through diet. Chlorophyll is the generic name for green plant pigments which includes the open-chain bile pigments and the large ring compounds. The structure of chlorophyll molecule has four nitrogen-containing pyrrole rings bonded to a central magnesium atom and the fifth ring containing only carbon atoms and various long hydrocarbon tails attached to the pyrrole rings. Carotenoids contain sequences of conjugated isoprene units alternating double and single carbon bonds. They are sometimes terminated by cyclic end-groups (rings) complemented with hydroxylated oxidized and hydrogenated groups. The conjugated double bonds absorbs light and UV. The more number of double bonds result in the absorbance of red color wavelength. Changes in geometrical configuration about the double bonds result in the existence of many cis- and trans- isomers. Carotenoids are usually located in quantity in the grana of chloroplasts in the form of carotenoprotein complexes which give blue green purple red or other colors to the outer surfaces in plants or eggs of crustaceans such as the lobster and crab. Carotenoids are classified into carotenes (un-oxidized carotenoids orange pigments) or xanthophylls (yellow pigments) which contains oxygen and are alcohol-soluble. It is known that more than 600 carotenoids are isolated from natural sources.
4. gamma-Lutein (xanthophyll)
Carotene: though carotene is the simplest of a group of natural pigments called carotenoids it has an unsaturated and long aliphatic hydrocarbon chain. It is found as a fat-soluble pigment in many higher plants of dark green leafy and yellow vegetables such as carrots collards turnips sweet potatoes and squash and in yellow fruits such as apricots oranges peaches and cantaloupes. Carotene is thought to transport light energy for photosynthesis or contribute to reduction reaction. It is important in animal biology as it is are converted to retinol in the body by an enzyme in the intestinal wall and the liver. Carotene occurs in several isomeric forms: alpha beta gamma delta epsilon and zeta of which the form of beta acts as an antioxidant nutrient protecting the body from damaging molecules called free radicals and an immune system booster as it is converted to vitamin A (retinol) important in animal biology as the main dietary source. One molecule of beta-carotene splits into two molecules of vitamin A and thus Beta-carotene is called provitamin A. Cryptoxanthin is a yellow carotenoid widely distributed in egg yolk green grass yellow corn which can be converted into vitamin A in the body. Cryptoxanthin is the major precursor of vitamin A together with beta-carotene in humans.
Trans-Beta-Carotene; Provatene; Provitamin A; Natural Yellow 26;
áá-caroteno (Spanish); betabeta-carotene; 11'-(371216-tetramethyl-1357911131517- Octadecanonaene-118-diyl) Bis(266-trimethyl- (All-e)-Cyclohexene;
PHYSICAL STATE: red to brown powder or crystals
MELTING POINT: 176 - 183 C (Decomposes)
SOLUBILITY IN WATER: insoluble
MOL WT: 536.90
STABILITY: Stable under ordinary conditions
EXAMPLES OF NATURALLY-OCCURRING CAROTENOIDS: