Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals and chain reactions that may damage the cells of organisms. Antioxidants such as thiols or ascorbic acid may act to inhibit these reactions. To balance oxidative stress, organisms contain and produce antioxidants, such as glutathione, mycothiol or bacillithiol.
Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids.
Umbelliferone, also known as 7-hydroxycoumarin, hydrangine, skimmetine, and beta-umbelliferone, is a natural product of the coumarin family.
Caffeic acid is an organic compound that is classified as a hydroxycinnamic acid. This yellow solid consists of both phenolic and acrylic functional groups. It is found in all plants because it is an intermediate in the biosynthesis of lignin, one of the principal components of woody plant biomass and its residues.
Terminalia chebula, commonly known as black- or chebulic myrobalan, is a species of Terminalia, native to South Asia from India and Nepal east to southwest China (Yunnan), and south to Sri Lanka, Malaysia, and Vietnam.
Chebulagic acid is a benzopyran tannin and an antioxidant that has many potential uses in medicine.
Ethyl gallate is a food additive with E number E313. It is the ethyl ester of gallic acid. Ethyl gallate is added to food as an antioxidant.
A depside is a type of polyphenolic compound composed of two or more monocyclic aromatic units linked by an ester bond. Depsides are most often found in lichens, but have also been isolated from higher plants, including species of the Ericaceae, Lamiaceae, Papaveraceae and Myrtaceae.
Chebulinic acid is an ellagitannin found in the seeds of Euphoria longana, in the fruits of Terminalia chebula or in the leaves of T. macroptera.
A hydrolyzable tannin or pyrogallol-type tannin is a type of tannin that, on heating with hydrochloric or sulfuric acids, yields gallic or ellagic acids.
In biochemistry, naturally occurring phenols refers to phenol functional group that is found in natural products. Phenolic compounds are produced by plants and microorganisms. Organisms sometimes synthesize phenolic compounds in response to ecological pressures such as pathogen and insect attack, UV radiation and wounding. As they are present in food consumed in human diets and in plants used in traditional medicine of several cultures, their role in human health and disease is a subject of research. Some phenols are germicidal and are used in formulating disinfectants.
A quinone methide is a type of conjugated organic compound that contain a cyclohexadiene with a carbonyl and an exocyclic methylidene or extended alkene unit. It is analogous to a quinone, but having one of the double bonded oxygens replaced with a carbon. The carbonyl and methylidene are usually oriented either ortho or para to each other. There are some examples of transient synthetic meta quinone methides.
Miquelianin is a flavonol glucuronide, a type of phenolic compound present in wine, in species of St John's wort, like Hypericum hirsutum, in Nelumbo nucifera or in green beans.
Punicalin is an ellagitannin. It can be found in Punica granatum (pomegranate) or in the leaves of Terminalia catappa, a plant used to treat dermatitis and hepatitis. It is also reported in Combretum glutinosum, all three species being Myrtales, the two last being Combretaceae.
The pomegranate ellagitannins, which include punicalagin isomers, are ellagitannins found in the sarcotestas, rind (peel), bark or heartwood of pomegranates.
Sanguiin H-6 is an ellagitannin.
Terminalia macroptera is a species of flowering plant in the Combretaceae known by the Hausa common name kwandari. It is native to Africa, where it can be found in Benin, Burkina Faso, Ghana, Senegal, Sudan, Uganda, and Nigeria.
Cucurbitacin E is a biochemical compound from the family of cucurbitacins. These are found in plants which are member of the family Cucurbitaceae, most of them coming from traditional Chinese medicinal plants, but also in other plants such as pumpkins and gourds.
Tellimagrandin I is an ellagitannin found in plants, such as Cornus canadensis, Eucalyptus globulus, Melaleuca styphelioides, Rosa rugosa, and walnut. It is composed of two galloyl and one hexahydroxydiphenyl groups bound to a glucose residue. It differs from Tellimagrandin II only by a hydroxyl group instead of a third galloyl group. It is also structurally similar to punigluconin and pedunculagin, two more ellagitannin monomers.
Salazinic acid is a depsidone with a lactone ring. It is found in some lichens, and is especially prevalent in Parmotrema and Bulbothrix, where its presence or absence is often used to help classify species in those genera.
