List of antioxidants in food
Encyclopedia
Vitamins
- Vitamin AVitamin AVitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light and color vision...
(retinol), also synthesizedBiosynthesisBiosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step...
by the body from beta-caroteneBeta-caroteneβ-Carotene is a strongly-coloured red-orange pigment abundant in plants and fruits. It is an organic compound and chemically is classified as a hydrocarbon and specifically as a terpenoid , reflecting its derivation from isoprene units...
, protects dark green, yellow and orange vegetables and fruits from solar radiation damage, and is thought to play a similar role in the human body. CarrotCarrotThe carrot is a root vegetable, usually orange in colour, though purple, red, white, and yellow varieties exist. It has a crisp texture when fresh...
s, squashSquash (fruit)Squashes generally refer to four species of the genus Cucurbita, also called marrows depending on variety or the nationality of the speaker...
, broccoliBroccoliBroccoli is a plant in the cabbage family, whose large flower head is used as a vegetable.-General:The word broccoli, from the Italian plural of , refers to "the flowering top of a cabbage"....
, sweet potatoSweet potatoThe sweet potato is a dicotyledonous plant that belongs to the family Convolvulaceae. Its large, starchy, sweet-tasting, tuberous roots are an important root vegetable. The young leaves and shoots are sometimes eaten as greens. Of the approximately 50 genera and more than 1,000 species of...
es, tomatoTomatoThe word "tomato" may refer to the plant or the edible, typically red, fruit which it bears. Originating in South America, the tomato was spread around the world following the Spanish colonization of the Americas, and its many varieties are now widely grown, often in greenhouses in cooler...
es (which gain their color from the compound lycopeneLycopeneLycopene is a bright red carotene and carotenoid pigment and phytochemical found in tomatoes and other red fruits and vegetables, such as red carrots, watermelons and papayas...
), kaleKaleKale is very high in beta carotene, vitamin K, vitamin C, lutein, zeaxanthin, and reasonably rich in calcium. Kale, as with broccoli and other brassicas, contains sulforaphane , a chemical with potent anti-cancer properties. Boiling decreases the level of sulforaphane; however, steaming,...
, mangoMangoThe mango is a fleshy stone fruit belonging to the genus Mangifera, consisting of numerous tropical fruiting trees in the flowering plant family Anacardiaceae. The mango is native to India from where it spread all over the world. It is also the most cultivated fruit of the tropical world. While...
es, orangesOrange (fruit)An orange—specifically, the sweet orange—is the citrus Citrus × sinensis and its fruit. It is the most commonly grown tree fruit in the world....
, seabuckthorn berries, wolfberries (goji), collards, cantaloupeCantaloupe"Rockmelon" redirects here, for the band see Rockmelons. See also Cantaloupe .Cantaloupe refers to a variety of Cucumis melo, a species in the family Cucurbitaceae which includes nearly all melons and squashes. Cantaloupes range in size from...
, peachPeachThe peach tree is a deciduous tree growing to tall and 6 in. in diameter, belonging to the subfamily Prunoideae of the family Rosaceae. It bears an edible juicy fruit called a peach...
es and apricotApricotThe apricot, Prunus armeniaca, is a species of Prunus, classified with the plum in the subgenus Prunus. The native range is somewhat uncertain due to its extensive prehistoric cultivation.- Description :...
s are particularly rich sources of beta-caroteneBeta-caroteneβ-Carotene is a strongly-coloured red-orange pigment abundant in plants and fruits. It is an organic compound and chemically is classified as a hydrocarbon and specifically as a terpenoid , reflecting its derivation from isoprene units...
, the major provitamin A carotenoidCarotenoidCarotenoids are tetraterpenoid organic pigments that are naturally occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some bacteria, and some types of fungus. Carotenoids can be synthesized fats and other basic organic metabolic building...
. - Vitamin CVitamin CVitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...
(ascorbic acid) is a water-soluble compound that fulfills several roles in living systems. Important sources include citrusCitrusCitrus is a common term and genus of flowering plants in the rue family, Rutaceae. Citrus is believed to have originated in the part of Southeast Asia bordered by Northeastern India, Myanmar and the Yunnan province of China...
fruits (such as orangesOrange (fruit)An orange—specifically, the sweet orange—is the citrus Citrus × sinensis and its fruit. It is the most commonly grown tree fruit in the world....
, sweet lime, etc.), green peppers, broccoliBroccoliBroccoli is a plant in the cabbage family, whose large flower head is used as a vegetable.-General:The word broccoli, from the Italian plural of , refers to "the flowering top of a cabbage"....
, green leafy vegetables, black currants, strawberries, blueberries, seabuckthorn, raw cabbageCabbageCabbage is a popular cultivar of the species Brassica oleracea Linne of the Family Brassicaceae and is a leafy green vegetable...
and tomatoTomatoThe word "tomato" may refer to the plant or the edible, typically red, fruit which it bears. Originating in South America, the tomato was spread around the world following the Spanish colonization of the Americas, and its many varieties are now widely grown, often in greenhouses in cooler...
es. Linus PaulingLinus PaulingLinus Carl Pauling was an American chemist, biochemist, peace activist, author, and educator. He was one of the most influential chemists in history and ranks among the most important scientists of the 20th century...
was a major advocate for its use. - Vitamin EVitamin EVitamin E is used to refer to a group of fat-soluble compounds that include both tocopherols and tocotrienols. There are many different forms of vitamin E, of which γ-tocopherol is the most common in the North American diet. γ-Tocopherol can be found in corn oil, soybean oil, margarine and dressings...
, including tocotrienolTocotrienolTocotrienols are members of the vitamin E family. An essential nutrient for the body, vitamin E is made up of four tocopherols and four tocotrienols . The slight difference between tocotrienols and tocopherols lie in the unsaturated side chain having three double bonds in its farnesyl isoprenoid...
and tocopherolTocopherolTocopherols are a class of chemical compounds of which many have vitamin E activity. It is a series of organic compounds consisting of various methylated phenols...
, is fat soluble and protects lipidLipidLipids constitute a broad group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins , monoglycerides, diglycerides, triglycerides, phospholipids, and others...
s. Sources include wheat germ, seabuckthorn, nutsNut (fruit)A nut is a hard-shelled fruit of some plants having an indehiscent seed. While a wide variety of dried seeds and fruits are called nuts in English, only a certain number of them are considered by biologists to be true nuts...
, seedSeedA seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s, whole grainWhole grainWhole grains are cereal grains that contain cereal germ, endosperm, and bran, in contrast to refined grains, which retain only the endosperm. Whole grains can generally be sprouted while refined grains generally will not sprout. Whole-meal products are made by grinding whole grains in order to make...
s, green leafy vegetables, kiwifruitKiwifruitThe kiwifruit, often shortened to kiwi in many parts of the world, is the edible berry of a cultivar group of the woody vine Actinidia deliciosa and hybrids between this and other species in the genus Actinidia....
, vegetable oil, and fish-liver oilCod liver oilCod liver oil is a nutritional supplement derived from liver of cod fish. It has high levels of the omega-3 fatty acids, EPA and DHA, and very high levels of vitamin A and vitamin D. It is widely taken to ease the symptoms of arthritis and for other health benefits...
. Alpha-tocopherol is the main form in which vitamin E is consumed. Recent studies showed that some tocotrienol isomers have significant anti-oxidant properties.
Vitamin cofactors and minerals
- Coenzyme QCoenzyme QCoenzyme Q10, also known as ubiquinone, ubidecarenone, coenzyme Q, and abbreviated at times to CoQ10 , CoQ, Q10, or Q, is a 1,4-benzoquinone, where Q refers to the quinone chemical group, and 10 refers to the number of isoprenyl chemical subunits in its tail.This oil-soluble, vitamin-like substance...
10 - ManganeseManganeseManganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals...
, particularly when in its +2 valence state as part of the enzyme called superoxide dismutaseSuperoxide dismutaseSuperoxide dismutases are a class of enzymes that catalyze the dismutation of superoxide into oxygen and hydrogen peroxide. As such, they are an important antioxidant defense in nearly all cells exposed to oxygen...
(SOD). - IodideIodideAn iodide ion is the ion I−. Compounds with iodine in formal oxidation state −1 are called iodides. This page is for the iodide ion and its salts. For information on organoiodides, see organohalides. In everyday life, iodide is most commonly encountered as a component of iodized salt,...
Carotenoid terpenoids
-
- Alpha-caroteneAlpha-caroteneα-Carotene is a form of carotene with a β-ring at one end and an ε-ring at the other. It is the second most common form of carotene.-Human physiology:...
- AstaxanthinAstaxanthinAstaxanthin is a carotenoid. It belongs to a larger class of phytochemicals known as terpenes. It is classified as a xanthophyll, which means "yellow leaves". Like many carotenoids, it is a colorful, lipid-soluble pigment. Astaxanthin is found in microalgae, yeast, salmon, trout, krill, shrimp,...
- found naturally in red algaeRed algaeThe red algae are one of the oldest groups of eukaryotic algae, and also one of the largest, with about 5,000–6,000 species of mostly multicellular, marine algae, including many notable seaweeds...
and animals higher in the marine food chain. It is a red pigment familiarly recognized in crustacean shells and salmon flesh/roe. - Beta-caroteneBeta-caroteneβ-Carotene is a strongly-coloured red-orange pigment abundant in plants and fruits. It is an organic compound and chemically is classified as a hydrocarbon and specifically as a terpenoid , reflecting its derivation from isoprene units...
- found in high concentrations in butternut squash, carrots, orange bell peppers, pumpkins, and sweet potatoes. - CanthaxanthinCanthaxanthinCanthaxanthin is a carotenoid pigment widely distributed in nature. Carotenoids belong to a larger class of phytochemicals known as terpenoids. The chemical formula of canthaxanthin is C40H52O2. It has E number E161g and is approved for use in the EU and USA however it is not approved for usage in...
- LuteinLuteinLutein is a xanthophyll and one of 600 known naturally occurring carotenoids. Lutein is synthesized only by plants and like other xanthophylls is found in high quantities in green leafy vegetables such as spinach and kale...
- found in high concentration in spinach, kiwifruit and red peppers. - LycopeneLycopeneLycopene is a bright red carotene and carotenoid pigment and phytochemical found in tomatoes and other red fruits and vegetables, such as red carrots, watermelons and papayas...
- found in high concentration in ripe red tomatoes and watermelons. - ZeaxanthinZeaxanthinZeaxanthin is one of the most common carotenoid alcohols found in nature. It is important in the xanthophyll cycle. Synthesized in plants & some micro-organisms, it is the pigment that gives paprika , corn, saffron, and many other plants & microbes their characteristic color.The name is derived...
- the main pigment found in yellow corn. It is also abundant in kiwifruit.
- Alpha-carotene
Flavonoid polyphenolics
FlavonoidFlavonoid
Flavonoids , are a class of plant secondary metabolites....
s, a subset of polyphenol antioxidant
Polyphenol antioxidant
A polyphenol antioxidant is a type of antioxidant containing a polyphenolic substructure. Numbering over 4,000 distinct species, many of these compounds have antioxidant activity in vitro but are unlikely to have antioxidant roles in vivo...
s, are present in many berries, as well as in coffee
Coffee
Coffee is a brewed beverage with a dark,init brooo acidic flavor prepared from the roasted seeds of the coffee plant, colloquially called coffee beans. The beans are found in coffee cherries, which grow on trees cultivated in over 70 countries, primarily in equatorial Latin America, Southeast Asia,...
and tea
Tea
Tea is an aromatic beverage prepared by adding cured leaves of the Camellia sinensis plant to hot water. The term also refers to the plant itself. After water, tea is the most widely consumed beverage in the world...
.
- FlavonesFlavonesFlavones , are a class of flavonoids based on the backbone of 2-phenylchromen-4-one shown on the right....
:- ApigeninApigeninApigenin is a flavone that is the aglycone of several glycosides. It is a yellow crystalline solid that has been used to dye wool. Apigenin may contribute to the chemopreventive action of vegetables and fruits...
- LuteolinLuteolinLuteolin is a yellow crystalline compound. It is a flavonoid; to be specific, it is one of the more common flavones. From preliminary research, it is thought to play a role in the human body possibly as an antioxidant, a free radical scavenger, a promoter of carbohydrate metabolism, or an immune...
- TangeritinTangeritinTangeritin is an O-polymethoxylated flavone that is found in tangerine and other citrus peels. Tangeritin strengthens the cell wall and protects it from invasion ....
- Apigenin
- FlavonolsFlavonolsFlavonols are a class of flavonoids that have the 3-hydroxyflavone backbone . Their diversity stems from the different positions the phenolic -OH groups. They are distinct from flavanols , another class of flavonoids.Flavonols are present in a wide variety of fruits and vegetables...
:- IsorhamnetinIsorhamnetinIsorhamnetin is an O-methylated flavonol, a type of chemical compound. It can be found in Tagetes lucida, a psychedelic plant from Mexico and Central America.-Metabolism:...
- KaempferolKaempferolKaempferol is a natural flavonol, a type of flavonoid, that has been isolated from tea, broccoli, Delphinium, Witch-hazel, grapefruit,cabbage, kale, beans, endive, leek, tomato, strawberries, grapes, brussels sprouts, apples and other plant sources. Kaempferol is a yellow crystalline solid with a...
- MyricetinMyricetinMyricetin is a naturally occurring flavonol, a flavonoid found in many grapes, berries, fruits, vegetables, herbs, as well as other plants. Walnuts are a rich dietary source. Trace amounts can be found as glycosides. It is one of the phenolic compounds present in red wine.Myricetin has antioxidant...
- walnutWalnutJuglans is a plant genus of the family Juglandaceae, the seeds of which are known as walnuts. They are deciduous trees, 10–40 meters tall , with pinnate leaves 200–900 millimetres long , with 5–25 leaflets; the shoots have chambered pith, a character shared with the wingnuts , but not the hickories...
s are a rich source - ProanthocyanidinProanthocyanidinProanthocyanidins, also known as OPCs or condensed tannins, are a subgroup of the flavonoid class of polyphenols...
s, or condensed tannins - QuercetinQuercetinQuercetin , a flavonol, is a plant-derived flavonoid found in fruits, vegetables, leaves and grains. It also may be used as an ingredient in supplements, beverages or foods.-Occurrence:...
and related, such as rutinRutinRutin, also called rutoside, quercetin-3-O-rutinoside and sophorin, is a citrus flavonoid glycoside found in buckwheat, the leaves and petioles of Rheum species, and asparagus...
- Isorhamnetin
- Flavanones:
- EriodictyolEriodictyolEriodictyol is a bitter-masking flavanone, a flavonoid extracted from Yerba Santa , a plant native to North America...
- HesperetinHesperetinHesperetin is a bioflavonoid and, to be more specific, a flavanone. Hesperidin is water-soluble due to the presence of the sugar part in its structure, so on ingestion it releases its aglycone, i.e, hesperetin....
(metabolizes to hesperidinHesperidinHesperidin is a flavanone glycoside found abundantly in citrus fruits. Its aglycone form is called hesperetin. Its name is derived from the Hesperides nymphs of Greek mythology. Hesperidin is believed to play a role in plant defense. It acts as an antioxidant according to in vitro studies...
) - NaringeninNaringeninNaringenin is a flavanone, a type of flavonoid, that is considered to have a bioactive effect on human health as antioxidant, free radical scavenger, anti-inflammatory, carbohydrate metabolism promoter, and immune system modulator. It is the predominant flavanone in grapefruit.-Biological...
(metabolized from naringinNaringinNaringin is a flavanone glycoside. It is a major flavonoid in grapefruit and gives the grapefruit juice its bitter taste. It is metabolized to the flavanone naringenin in humans...
)
- Eriodictyol
- Flavanols and their polymers:
- CatechinCatechinCatechin is a natural phenol antioxidant plant secondary metabolite. The term catechins is also commonly used to refer to the related family of flavonoids and the subgroup flavan-3-ols ....
, gallocatechin and their corresponding gallateGallic acidGallic acid is a trihydroxybenzoic acid, a type of phenolic acid, a type of organic acid, also known as 3,4,5-trihydroxybenzoic acid, found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. The chemical formula is C6H23COOH. Gallic acid is found both free and as part of...
esters - Epicatechin, epigallocatechin and their corresponding gallate esters
- TheaflavinTheaflavinTheaflavin and its derivatives, known collectively as theaflavins, are antioxidant polyphenols that are formed from flavan-3-ols such as in tea leaves during the enzymatic oxidation of tea leaves, such as in black tea. Theaflavins are types of thearubigins, and are therefore reddish in color...
its gallate esters - ThearubiginThearubiginThearubigins are polymeric polyphenols that are formed during the enzymatic oxidation of tea leaves. Thearubigins are red in colour. Therefore a black tea gives a reddish liquor while a green or white tea gives a much clearer one...
s
- Catechin
- IsoflavoneIsoflavoneIsoflavones comprise a class of organic compounds, often naturally occurring, related to the isoflavonoids. Many act as phytoestrogens in mammals...
phytoestrogensPhytoestrogensPhytoestrogens are plant-derived xenoestrogens functioning as the primary female sex hormone not generated within the endocrine system but consumed by eating phytoestrogonic plants...
- found primarily in soy, peanuts, and other members of the Fabaceae family- DaidzeinDaidzeinDaidzein belongs to the group of isoflavones. Daidzein and other isoflavone compounds, such as genistein, are present in a number of plants and herbs like the Thai Kwao Krua or Pueraria mirifica, Kudzu or Pueraria lobata, and in food sources such as soybeans and soy products like tofu and textured...
- GenisteinGenisteinGenistein is one of several known isoflavones. Isoflavones, such as genistein and daidzein, are found in a number of plants including lupin, fava beans, soybeans, kudzu, and psoralea being the primary food source, also in the medicinal plant, Flemingia vestita and coffee Besides functioning as...
- GlyciteinGlyciteinGlycitein is an O-methylated isoflavone which accounts for 5-10% of the total isoflavones in soy food products. Glycitein is a phytoestrogen with weak estrogenic activity, comparable to that of the other soy isoflavones....
- Daidzein
- StilbenoidsStilbenoidsStilbenoids are secondary products of heartwood formation in trees that can act as phytoalexins. In chemical terms, they are hydroxylated derivatives of stilbene. In biochemical terms, they belong to the family of phenylpropanoids and share most of their biosynthesis pathway with chalcones...
:- ResveratrolResveratrolResveratrol is a stilbenoid, a type of natural phenol, and a phytoalexin produced naturally by several plants when under attack by pathogens such as bacteria or fungi....
- found in the skins of dark-colored grapes, and concentrated in red wine. - PterostilbenePterostilbenePterostilbene is a stilbenoid chemically related to resveratrol and is found in blueberries and grapes. It belongs to the group of phytoalexins, agents produced by plants to fight infections. Based on animal studies it is thought to exhibit anti-cancer, anti-hypercholesterolemia,...
- methoxylated analogue of resveratrol, abundant in VacciniumVacciniumVaccinium is a genus of shrubs or dwarf shrubs in the plant Family Ericaceae. The fruit of many species are eaten by humans and some are of commercial importance, including the cranberry, blueberry, bilberry or whortleberry, lingonberry or cowberry, and huckleberry...
berries
- Resveratrol
- Anthocyanins
- CyanidinCyanidinCyanidin is a natural organic compound. It is a particular type of anthocyanidin . It is a pigment found in many red berries including but not limited to grapes, bilberry, blackberry, blueberry, cherry, cranberry, elderberry, hawthorn, loganberry, acai berry and raspberry...
- DelphinidinDelphinidinDelphinidin is an anthocyanidin, a primary plant pigment, and also an antioxidant. Delphinidin gives blue hues to flowers like violas and delphiniums...
- MalvidinMalvidinMalvidin is an O-methylated anthocyanidin. As a primary plant pigment, its glycosides are highly abundant in nature. It is responsible primarily for the color of red wine, Vitis vinifera being one of its sources...
- PelargonidinPelargonidinPelargonidin is an anthocyanidin, a type of plant pigment. Like all anthocyanins, it is an antioxidant. It produces a characteristic orange color, and can be found in red geraniums, and ripe raspberries and strawberries, as well as blueberries, blackberries, plums and cranberries and pomegranates....
- PeonidinPeonidinPeonidin is an O-methylated anthocyanidin, and a primary plant pigment. Peonidin gives purplish-red hues to flowers such as the peony, from which it takes its name, and roses. It is also present in some blue flowers, such as the morning glory....
- PetunidinPetunidinPetunidin is an O-methylated anthocyanidin. It is a natural organic compound and a particular type of anthocyanidin. It is a dark-red or purple water-soluble pigment found in many redberries including chokeberries , Saskatoon berries or different species of grape , and...
- Cyanidin
Phenolic acids and their esters
-
- Chicoric acid - another caffeic acid derivative, is found only in the popular medicinal herb EchinaceaEchinaceaEchinacea is a genus of herbaceous flowering plants in the daisy family, Asteraceae. The nine species it contains are commonly called purple coneflowers. They are endemic to eastern and central North America, where they are found growing in moist to dry prairies and open wooded areas. They have...
purpurea. - Chlorogenic acidChlorogenic acidChlorogenic acid is a hydroxycinnamic acid, a member of a family of naturally occurring organic compounds. These are esters of polyphenolic caffeic acid and cyclitol -quinic acid. It is an important biosynthetic intermediate. It also is one of the phenols found in coffee, bamboo Phyllostachys...
- found in high concentration in coffee (more concentrated in robusta than arabica beans), blueberries and tomatoes. Produced from esterification of caffeic acid. - Cinnamic acidCinnamic acidCinnamic acid is a white crystalline organic acid, which is slightly soluble in water.It is obtained from oil of cinnamon, or from balsams such as storax. It is also found in shea butter and is the best indication of its environmental history and post-extraction conditions...
and its derivatives, such as ferulic acidFerulic acidFerulic acid is a hydroxycinnamic acid, a type of organic compound. It is an abundant phenolic phytochemical found in plant cell wall components such as arabinoxylans as covalent side chains. It is related to trans-cinnamic acid. As a component of lignin, ferulic acid is a precursor in the...
- found in seeds of plants such as in brown rice, whole wheat and oats, as well as in coffee, apple, artichoke, peanut, orange and pineapple. - Ellagic acidEllagic acidEllagic acid is a natural phenol antioxidant found in numerous fruits and vegetables including blackberries, raspberries, strawberries, cranberries, walnuts, pecans, pomegranates, wolfberry and other plant foods...
- found in high concentration in raspberryRaspberryThe raspberry or hindberry is the edible fruit of a multitude of plant species in the genus Rubus, most of which are in the subgenus Idaeobatus; the name also applies to these plants themselves...
and strawberryStrawberryFragaria is a genus of flowering plants in the rose family, Rosaceae, commonly known as strawberries for their edible fruits. Although it is commonly thought that strawberries get their name from straw being used as a mulch in cultivating the plants, the etymology of the word is uncertain. There...
, and in ester form in red wine tannins. - EllagitanninEllagitanninThe ellagitannins are a diverse class of hydrolyzable tannins, a type of polyphenol formed primarily from the oxidative linkage of galloyl groups in 1,2,3,4,6-Pentagalloyl glucose...
s - hydrolyzable tannin polymer formed when ellagic acid, a polyphenol monomer, esterifies and binds with the hydroxyl group of a polyol carbohydrate such as glucose. - Gallic acidGallic acidGallic acid is a trihydroxybenzoic acid, a type of phenolic acid, a type of organic acid, also known as 3,4,5-trihydroxybenzoic acid, found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. The chemical formula is C6H23COOH. Gallic acid is found both free and as part of...
- found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and many other plants. - GallotanninGallotanninA gallotannin is a class of molecules belonging to the hydrolysable tannins. Gallotannins are polymers formed when gallic acid, a polyphenol monomer, esterifies and binds with the hydroxyl group of a polyol carbohydrate such as glucose.-Metabolism:...
s - hydrolyzable tannin polymer formed when gallic acid, a polyphenol monomer, esterifies and binds with the hydroxyl group of a polyol carbohydrate such as glucose. - Rosmarinic acidRosmarinic acidRosmarinic acid, C18H16O8, is a natural phenol antioxidant carboxylic acid found in many Lamiaceae herbs used commonly as culinary herbs such as lemon balm, rosemary, oregano, sage, thyme and peppermint. Chemically, rosmarinic acid is an ester of caffeic acid with 3,4-dihydroxyphenyl lactic acid...
- found in high concentration in rosemaryRosemaryRosemary, , is a woody, perennial herb with fragrant, evergreen, needle-like leaves and white, pink, purple or blue flowers, native to the Mediterranean region. It is a member of the mint family Lamiaceae, which includes many other herbs, and is one of two species in the genus Rosmarinus...
, oreganoOreganoOregano – scientifically named Origanum vulgare by Carolus Linnaeus – is a common species of Origanum, a genus of the mint family . It is native to warm-temperate western and southwestern Eurasia and the Mediterranean region.Oregano is a perennial herb, growing from 20–80 cm tall,...
, lemon balmLemon balmLemon balm , not to be confused with bee balm, Monarda species, is a perennial herb in the mint family Lamiaceae, native to southern Europe and the Mediterranean region....
, sageCommon sageSalvia officinalis is a small, perennial, evergreen subshrub, with woody stems, grayish leaves, and blue to purplish flowers. It is a member of the family Lamiaceae and is native to the Mediterranean region, though it has naturalized in many places throughout the world...
, and marjoramMarjoramMarjoram is a somewhat cold-sensitive perennial herb or undershrub with sweet pine and citrus flavours...
. - Salicylic acidSalicylic acidSalicylic acid is a monohydroxybenzoic acid, a type of phenolic acid and a beta hydroxy acid. This colorless crystalline organic acid is widely used in organic synthesis and functions as a plant hormone. It is derived from the metabolism of salicin...
- found in most vegetables, fruits, and herbs; but most abundantly in the bark of willow trees, from where it was extracted for use in the early manufacture of aspirinAspirinAspirin , also known as acetylsalicylic acid , is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. It was discovered by Arthur Eichengrun, a chemist with the German company Bayer...
.
- Chicoric acid - another caffeic acid derivative, is found only in the popular medicinal herb Echinacea
Other nonflavonoid phenolics
- CurcuminCurcuminCurcumin is the principal curcuminoid of the popular Indian spice turmeric, which is a member of the ginger family . The other two curcuminoids are desmethoxycurcumin and bis-desmethoxycurcumin. The curcuminoids are natural phenols and are responsible for the yellow color of turmeric...
- Curcumin has low bioavailability, because, much of it is excreted through glucuronidationGlucuronidationGlucuronidation is the addition of glucuronic acid to a substrate. Glucuronidation is often involved in xenobiotic metabolism of substances such as drugs, pollutants, bilirubin, androgens, estrogens, mineralocorticoids, glucocorticoids, fatty acid derivatives, retinoids, and bile acids...
. However, bioavailability is substantially enhanced by solubilization in a lipid (oil or lecithin), heat, addition of piperine, or through nanoparticularization. - Flavonolignans - e.g. silymarin - a mixture of flavonolignans extracted from milk thistleMilk thistleThe milk thistle is a thistle of the genus Silybum Adans., a flowering plant of the daisy family . They are native to the Mediterranean regions of Europe, North Africa and the Middle East...
. - XanthoneXanthoneXanthone is an organic compound with the molecular formula C13H8O2. It can be prepared by the heating of phenyl salicylate. In 1939, xanthone was introduced as an insecticide and it currently finds uses as ovicide for codling moth eggs and as a larvicide...
s - mangosteenMangosteenThe purple mangosteen , colloquially known simply as mangosteen, is a tropical evergreen tree believed to have originated in the Sunda Islands and the Moluccas of Indonesia. The tree grows from 7 to 25 m tall...
is purported to contain a large variety of xanthones, but some of the xanthones like mangostinMangostinMangostin is a natural xanthonoid, a type of organic compound isolated from various parts of the mangosteen tree . It is a yellow crystalline solid with a xanthone core structure...
might be present only in the inedible shell. - EugenolEugenolEugenol is a phenylpropene, an allyl chain-substituted guaiacol. Eugenol is a member of the phenylpropanoids class of chemical compounds. It is a clear to pale yellow oily liquid extracted from certain essential oils especially from clove oil, nutmeg, cinnamon, basil and bay leaf. It is slightly...
Other potential organic antioxidants
- CapsaicinCapsaicinCapsaicin 2CHCH=CH4CONHCH2C6H3-4--3- ) is the active component of chili peppers, which are plants belonging to the genus Capsicum. It is an irritant for mammals, including humans, and produces a sensation of burning in any tissue with which it comes into contact...
, the active component of chili peppers - BilirubinBilirubinBilirubin is the yellow breakdown product of normal heme catabolism. Heme is found in hemoglobin, a principal component of red blood cells. Bilirubin is excreted in bile and urine, and elevated levels may indicate certain diseases...
, a breakdown product of blood, has been identified as a possible antioxidant. - Citric acidCitric acidCitric acid is a weak organic acid. It is a natural preservative/conservative and is also used to add an acidic, or sour, taste to foods and soft drinks...
, oxalic acidOxalic acidOxalic acid is an organic compound with the formula H2C2O4. This colourless solid is a dicarboxylic acid. In terms of acid strength, it is about 3,000 times stronger than acetic acid. Oxalic acid is a reducing agent and its conjugate base, known as oxalate , is a chelating agent for metal cations...
, and phytic acidPhytic acidPhytic acid is the principal storage form of phosphorus in many plant tissues, especially bran and seeds. Phytate is not digestible to humans or nonruminant animals, however, so it is not a source of either inositol or phosphate if eaten directly... - N-Acetylcysteine, water soluble
- R-α-Lipoic acidLipoic acidLipoic acid , also known as α-lipoic acid and Alpha Lipoic Acid is an organosulfur compound derived from octanoic acid. LA contains two vicinal sulfur atoms attached via a disulfide bond and is thus considered to be oxidized...
, fat and water soluble - Uric acidUric acidUric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates such as ammonium acid urate. Uric acid is created when the body breaks down purine nucleotides. High blood concentrations of uric acid...
, in humans, accounts for roughly half the antioxidant capacity of plasma. FructoseFructoseFructose, or fruit sugar, is a simple monosaccharide found in many plants. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed directly into the bloodstream during digestion. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847...
, which is found abundantly in fruits, significantly elevates uric acid levels in humans, and thus indirectly increases antioxidant capacity. High levels of uric acid may be a protective factor against Parkinson's disease and possibly other diseases related to oxidative stressOxidative stressOxidative stress represents an imbalance between the production and manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage...
.
Regulatory guidance
In the following discussion, the term "antioxidant" refers mainly to non-nutrient compounds in foods, such as polyphenols, which have antioxidant capacity in vitroIn vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
and so provide an artificial index of antioxidant strength – the ORAC measurement. Other than for dietary antioxidant vitamins – vitamin A
Vitamin A
Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light and color vision...
, vitamin C
Vitamin C
Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...
and vitamin E
Vitamin E
Vitamin E is used to refer to a group of fat-soluble compounds that include both tocopherols and tocotrienols. There are many different forms of vitamin E, of which γ-tocopherol is the most common in the North American diet. γ-Tocopherol can be found in corn oil, soybean oil, margarine and dressings...
– no food compounds have been proved with antioxidant efficacy in vivo
In vivo
In vivo is experimentation using a whole, living organism as opposed to a partial or dead organism, or an in vitro controlled environment. Animal testing and clinical trials are two forms of in vivo research...
. Accordingly, regulatory agencies like the Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
of the United States and the European Food Safety Authority
European Food Safety Authority
The European Food Safety Authority is an agency of the European Union that provides independent scientific advice and communication on existing and emerging risks associated with the food chain, created by European Regulation 178/2002....
(EFSA) have published guidance disallowing food product labels to claim an inferred antioxidant benefit when no such physiological evidence exists.
ORAC in foods
Many common foods are good sources of antioxidants. In the list of foods given below, "rich in antioxidants" usually means at least a ORAC rating of 1000 per 100 g. A typical apple or pear weighs around 200 g and hence 200 g can be considered as the serving size.Spices, herbs, essential oil
Essential oil
An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are also known as volatile oils, ethereal oils or aetherolea, or simply as the "oil of" the plant from which they were extracted, such as oil of clove...
s and cocoa
Chocolate
Chocolate is a raw or processed food produced from the seed of the tropical Theobroma cacao tree. Cacao has been cultivated for at least three millennia in Mexico, Central and South America. Its earliest documented use is around 1100 BC...
are rich in antioxidant properties in the plant itself and in vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
, but the serving size is too small to supply antioxidants via the diet. Typical spices high in antioxidants (confirmed in vitro) are clove
Clove
Cloves are the aromatic dried flower buds of a tree in the family Myrtaceae. Cloves are native to the Maluku islands in Indonesia and used as a spice in cuisines all over the world...
, cinnamon
Cinnamon
Cinnamon is a spice obtained from the inner bark of several trees from the genus Cinnamomum that is used in both sweet and savoury foods...
, oregano
Oregano
Oregano – scientifically named Origanum vulgare by Carolus Linnaeus – is a common species of Origanum, a genus of the mint family . It is native to warm-temperate western and southwestern Eurasia and the Mediterranean region.Oregano is a perennial herb, growing from 20–80 cm tall,...
, turmeric
Turmeric
Turmeric is a rhizomatous herbaceous perennial plant of the ginger family, Zingiberaceae. It is native to tropical South Asia and needs temperatures between 20 °C and 30 °C and a considerable amount of annual rainfall to thrive...
, cumin
Cumin
Cumin is a flowering plant in the family Apiaceae, native from the east Mediterranean to India. Its seeds are used in the cuisines of many different cultures, in both whole and ground form.-Etymology:...
, parsley
Parsley
Parsley is a species of Petroselinum in the family Apiaceae, native to the central Mediterranean region , naturalized elsewhere in Europe, and widely cultivated as an herb, a spice and a vegetable.- Description :Garden parsley is a bright green hairless biennial herbaceous plant in temperate...
, basil
Basil
Basil, or Sweet Basil, is a common name for the culinary herb Ocimum basilicum , of the family Lamiaceae , sometimes known as Saint Joseph's Wort in some English-speaking countries....
, curry powder
Curry powder
Curry powder is a mixture of spices of widely varying composition based on South Asian cuisine. Curry powder, and the contemporary English use of the word curry are Western inventions and do not reflect any specific Indian food, though a similar mixture of spices used in north India is called...
, mustard seed
Mustard seed
Mustard seeds are the small round seeds of various mustard plants. The seeds are usually about 1 or 2 mm in diameter. Mustard seeds may be colored from yellowish white to black. They are important spices in many regional foods. The seeds can come from three different plants: black mustard , brown...
, ginger
Ginger
Ginger is the rhizome of the plant Zingiber officinale, consumed as a delicacy, medicine, or spice. It lends its name to its genus and family . Other notable members of this plant family are turmeric, cardamom, and galangal....
, pepper
Black pepper
Black pepper is a flowering vine in the family Piperaceae, cultivated for its fruit, which is usually dried and used as a spice and seasoning. The fruit, known as a peppercorn when dried, is approximately in diameter, dark red when fully mature, and, like all drupes, contains a single seed...
, chili powder, paprika
Paprika
Paprika is a spice made from the grinding of dried fruits of Capsicum annuum . In many European languages, the word paprika refers to bell peppers themselves. The seasoning is used in many cuisines to add color and flavor to dishes. Paprika can range from mild to hot...
, garlic
Garlic
Allium sativum, commonly known as garlic, is a species in the onion genus, Allium. Its close relatives include the onion, shallot, leek, chive, and rakkyo. Dating back over 6,000 years, garlic is native to central Asia, and has long been a staple in the Mediterranean region, as well as a frequent...
, coriander
Coriander
Coriander is an annual herb in the family Apiaceae. Coriander is native to southern Europe and North Africa to southwestern Asia. It is a soft, hairless plant growing to tall. The leaves are variable in shape, broadly lobed at the base of the plant, and slender and feathery higher on the...
, onion
Onion
The onion , also known as the bulb onion, common onion and garden onion, is the most widely cultivated species of the genus Allium. The genus Allium also contains a number of other species variously referred to as onions and cultivated for food, such as the Japanese bunching onion The onion...
and cardamom
Cardamom
Cardamom refers to several plants of the genera Elettaria and Amomum in the ginger family Zingiberaceae. Both genera are native to India and Bhutan; they are recognised by their small seed pod, triangular in cross-section and spindle-shaped, with a thin papery outer shell and small black seeds...
. Typical herbs are sage, thyme
Thyme
Thyme is a culinary and medicinal herb of the genus Thymus.-History:Ancient Egyptians used thyme for embalming. The ancient Greeks used it in their baths and burnt it as incense in their temples, believing it was a source of courage...
, marjoram
Marjoram
Marjoram is a somewhat cold-sensitive perennial herb or undershrub with sweet pine and citrus flavours...
, tarragon
Tarragon
Tarragon or dragon's-wort is a perennial herb in the family Asteraceae related to wormwood. Corresponding to its species name, a common term for the plant is "dragon herb". It is native to a wide area of the Northern Hemisphere from easternmost Europe across central and eastern Asia to India,...
, peppermint
Peppermint
Peppermint is a hybrid mint, a cross between the watermint and spearmint . The plant, indigenous to Europe, is now widespread in cultivation throughout all regions of the world...
, oregano
Oregano
Oregano – scientifically named Origanum vulgare by Carolus Linnaeus – is a common species of Origanum, a genus of the mint family . It is native to warm-temperate western and southwestern Eurasia and the Mediterranean region.Oregano is a perennial herb, growing from 20–80 cm tall,...
, savory
Summer savory
Summer savory is the better known of the savory species. It is an annual, but otherwise is similar in use and flavor to the perennial winter savory...
, basil
Basil
Basil, or Sweet Basil, is a common name for the culinary herb Ocimum basilicum , of the family Lamiaceae , sometimes known as Saint Joseph's Wort in some English-speaking countries....
and dill weed.
Dried fruits are a good source of antioxidants by weight/serving size as the water has been removed making the ratio of antioxidants higher. Typical dried fruits are pears, apples, plums, peaches, raisins, figs and dates. Dried raisins are high in polyphenol count. Red wine is high in total polyphenol count which supplies antioxidant quality which is unlikely to be conserved following digestion (see section below).
Deeply pigmented fruits like cranberries, blueberries, plums, blackberries, raspberries, strawberries, blackcurrants, figs, cherries, guava, oranges, mango, grape juice and pomegranate juice also have significant ORAC scores.
Typical cooked vegetables rich in antioxidants are artichokes, cabbage, broccoli, asparagus
Asparagus
Asparagus officinalis is a spring vegetable, a flowering perennialplant species in the genus Asparagus. It was once classified in the lily family, like its Allium cousins, onions and garlic, but the Liliaceae have been split and the onion-like plants are now in the family Amaryllidaceae and...
, avocado
Avocado
The avocado is a tree native to Central Mexico, classified in the flowering plant family Lauraceae along with cinnamon, camphor and bay laurel...
s, beetroot and spinach.
Nuts are a moderate source of polyphenol antioxidants. Typical nuts are pecans, walnuts, hazelnuts, pistachio
Pistachio
The pistachio, Pistacia vera in the Anacardiaceae family, is a small tree originally from Persia , which now can also be found in regions of Syria, Lebanon, Turkey, Greece, Kyrgyzstan, Turkmenistan, India, Pakistan, Egypt, Sicily and possibly Afghanistan , as well as in the United States,...
, almonds, cashew nuts, macadamia nuts and peanut butter
Peanut butter
Peanut butter is a food paste made primarily from ground dry roasted peanuts, popular in North America, Netherlands, United Kingdom, and parts of Asia, particularly the Philippines and Indonesia. It is mainly used as a sandwich spread, sometimes in combination as in the peanut butter and jelly...
.
Sorghum bran, cocoa
Cocoa solids
Cocoa solids are the low-fat component of chocolate. When sold as an end product, it may also be called cocoa powder, cocoa, and cacao....
powder, and cinnamon
Cinnamon
Cinnamon is a spice obtained from the inner bark of several trees from the genus Cinnamomum that is used in both sweet and savoury foods...
are rich sources of procyanidins, which are large molecular weight compounds found in many fruits and some vegetables. Partly due to the large molecular weight (size) of these compounds, their amount actually absorbed in the body is low, an effect also resulting from the action of stomach acids, enzymes and bacteria in the gastrointestinal tract where smaller derivatives are metabolized and prepared for rapid excretion.
Physiological context
Despite the above discussion inferring that ORAC-rich foods with polyphenols may provide antioxidant benefits when in the diet, there remains no physiological evidence that any polyphenols have such actions or that ORAC has any relevance in the human body.On the contrary, research indicates that although polyphenols are good antioxidant
Antioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
s in vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
, antioxidant effects in vivo
In vivo
In vivo is experimentation using a whole, living organism as opposed to a partial or dead organism, or an in vitro controlled environment. Animal testing and clinical trials are two forms of in vivo research...
are probably negligible or absent. By non-antioxidant mechanisms still undefined, flavonoids and other polyphenols may reduce the risk of cardiovascular disease and cancer.
As interpreted by the Linus Pauling Institute
Linus Pauling Institute
The Linus Pauling Institute is a research institute located at Oregon State University with a focus on health maintenance. The mission statement of the institute is three-fold. First, to determine the functional roles of micronutrients and phytochemicals in promoting optimal health and to treat or...
and EFSA, dietary polyphenols have little or no direct antioxidant food value following digestion. Not like controlled test tube conditions, the fate of polyphenols in vivo
In vivo
In vivo is experimentation using a whole, living organism as opposed to a partial or dead organism, or an in vitro controlled environment. Animal testing and clinical trials are two forms of in vivo research...
shows they are poorly conserved (less than 5%), with most of what is absorbed existing as chemically-modified metabolites destined for rapid excretion.
The increase in antioxidant capacity of blood seen after the consumption of polyphenol-rich (ORAC-rich) foods is not caused directly by the polyphenols, but most likely results from increased uric acid
Uric acid
Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates such as ammonium acid urate. Uric acid is created when the body breaks down purine nucleotides. High blood concentrations of uric acid...
levels derived from metabolism of flavonoids. According to Frei, "we can now follow the activity of flavonoids in the body, and one thing that is clear is that the body sees them as foreign compounds and is trying to get rid of them." Another mechanism may be the increase in activities of paraoxonases by dietary antioxidants which can reduce oxidative stress.
See also
- AntioxidantAntioxidantAn antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
- Colour retention agentColour retention agentColour retention agents are food additives that are added to food to prevent the colour from changing. Many of them work by absorbing or binding to oxygen before it can damage food...
- NutritionNutritionNutrition is the provision, to cells and organisms, of the materials necessary to support life. Many common health problems can be prevented or alleviated with a healthy diet....
- Polyphenol antioxidantPolyphenol antioxidantA polyphenol antioxidant is a type of antioxidant containing a polyphenolic substructure. Numbering over 4,000 distinct species, many of these compounds have antioxidant activity in vitro but are unlikely to have antioxidant roles in vivo...
- Free radical