Epikatekiini

Epikatekiini, known in English as epicatechin, is a natural phenolic compound that belongs to the flavanol class of flavonoids. It is the enantiomer of catechin, commonly occurring as (-)-epicatechin, and serves as a monomer for larger proanthocyanidin polymers found in many plants.

Epicatechin occurs widely in the plant kingdom and is especially abundant in Theobroma cacao (cocoa beans and dark chocolate), Camellia sinensis (tea), apples, grapes, and various berries. In plants it contributes to the color, taste, and defense against stress. In foods, epicatechin is available both as a free compound and as part of polymeric proanthocyanidins.

Chemically, epicatechin is a flavanol with a dihydroxyphenyl ring and a chroman-3-ol structure. It is biosynthesized in the flavonoid pathway from phenylpropanoid metabolism and can be found in free form or bound within polymeric catechin–epicatechin units.

Biological activity and research suggest that epicatechin has antioxidant properties and may influence cardiovascular health by affecting endothelial function and nitric oxide signaling. Some studies report anti-inflammatory effects and possible benefits for mitochondrial function and exercise performance, but results in humans are mixed and highly dependent on dose, duration, and matrix (food vs. supplement). Epicatechin is not approved as a medical treatment, and its effects are not guaranteed for disease prevention or therapy.

Pharmacokinetics indicate limited oral bioavailability, with absorption followed by rapid metabolism to glucuronide and sulfate conjugates and excretion in urine. Dietary intake from cocoa and tea is generally safe, while high-dose supplements may pose risks and should be used with caution or medical advice.