Catechin: An antioxidant flavonoid, occurring especially in woody plants as both (+)-catechin and (-)-epicatechin (cis) forms.Tea: The infusion of leaves of CAMELLIA SINENSIS (formerly Thea sinensis) as a beverage, the familiar Asian tea, which contains CATECHIN (especially epigallocatechin gallate) and CAFFEINE.Camellia sinensis: Camellia sinensis L. (formerly Thea sinensis) is an evergreen Asiatic shrub of the THEACEAE family. The infusion of leaves of this plant is used as Oriental TEA which contains CAFFEINE; THEOPHYLLINE; and epigallocatechin gallate.Biflavonoids: Dimers (homo and hetero) of FLAVONOIDS.Polyphenols: A large class of organic compounds having more than one PHENOL group.Flavonoids: A group of phenyl benzopyrans named for having structures like FLAVONES.Gallic Acid: A colorless or slightly yellow crystalline compound obtained from nutgalls. It is used in photography, pharmaceuticals, and as an analytical reagent.Proanthocyanidins: Dimers and oligomers of flavan-3-ol units (CATECHIN analogs) linked mainly through C4 to C8 bonds to leucoanthocyanidins. They are structurally similar to ANTHOCYANINS but are the result of a different fork in biosynthetic pathways.Plant Extracts: Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.Phenols: Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.Antioxidants: Naturally occurring or synthetic substances that inhibit or retard the oxidation of a substance to which it is added. They counteract the harmful and damaging effects of oxidation in animal tissues.Camellia: A plant genus in the family THEACEAE, order THEALES best known for CAMELLIA SINENSIS which is the source of Oriental TEA.PicratesCentaurea: A plant genus of the family ASTERACEAE. Members contain 5-methyl-8-hydroxycoumarin. The common name of centaury is more often used for CENTAURIUMRutin: A flavonol glycoside found in many plants, including BUCKWHEAT; TOBACCO; FORSYTHIA; HYDRANGEA; VIOLA, etc. It has been used therapeutically to decrease capillary fragility.Tannins: Polyphenolic compounds with molecular weights of around 500-3000 daltons and containing enough hydroxyl groups (1-2 per 100 MW) for effective cross linking of other compounds (ASTRINGENTS). The two main types are HYDROLYZABLE TANNINS and CONDENSED TANNINS. Historically, the term has applied to many compounds and plant extracts able to render skin COLLAGEN impervious to degradation. The word tannin derives from the Celtic word for OAK TREE which was used for leather processing.Wine: Fermented juice of fresh grapes or of other fruit or plant products used as a beverage.Flavonols: A group of 3-hydroxy-4-keto-FLAVONOIDS.Cacao: A tree of the family Sterculiaceae (or Byttneriaceae), usually Theobroma cacao, or its seeds, which after fermentation and roasting, yield cocoa and chocolate.Quercetin: A flavonol widely distributed in plants. It is an antioxidant, like many other phenolic heterocyclic compounds. Glycosylated forms include RUTIN and quercetrin.Anthocyanins: A group of FLAVONOIDS derived from FLAVONOLS, which lack the ketone oxygen at the 4-position. They are glycosylated versions of cyanidin, pelargonidin or delphinidin. The conjugated bonds result in blue, red, and purple colors in flowers of plants.Protocatechuate-3,4-Dioxygenase: An enzyme that catalyzes the oxidation of protocatechuate to 3-carboxy-cis-cis-muconate in the presence of molecular oxygen. It contains ferric ion. EC 220.127.116.11.Free Radical Scavengers: Substances that influence the course of a chemical reaction by ready combination with free radicals. Among other effects, this combining activity protects pancreatic islets against damage by cytokines and prevents myocardial and pulmonary perfusion injuries.Transition Elements: Elements with partially filled d orbitals. They constitute groups 3-12 of the periodic table of elements.Paullinia: A plant genus of the family SAPINDACEAE. The seed of P. cupana is the source of guarana powder which contains 4% CAFFEINE.Anti-Obesity Agents: Agents that increase energy expenditure and weight loss by neural and chemical regulation. Beta-adrenergic agents and serotoninergic drugs have been experimentally used in patients with non-insulin dependent diabetes mellitus (NIDDM) to treat obesity.Cistus: A plant genus of the family CISTACEAE. The common name of rock rose is also sometimes used with the closely related Helianthemum genus (CISTACEAE).Combretum: A plant genus of the family COMBRETACEAE. Triterpenes and combretastatin have been identified in members of this genus.Bambusa: A plant genus of the family POACEAE. Young shoots are eaten in Asian foods while the stiff mature stems are used for construction of many things. The common name of bamboo is also used for other genera of Poaceae including Phyllostachys, SASA, and Dendrocalamus.Hydroxybenzoates: Benzoate derivatives substituted by one or more hydroxy groups in any position on the benzene ring.