Flavan-3-ols are a subgroup of flavonoids. They are derivatives of flavans that possess a 2-phenyl-3,4-dihydro-2H-chromen-3-ol skeleton. Flavan-3-ols are structurally diverse and include a range of compounds, such as catechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate, proanthocyanidins, theaflavins, thearubigins. They play a part in plant defense and are present in the majority of plants.
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.
Proanthocyanidins are a class of polyphenols found in many plants, such as cranberry, blueberry, and grape seeds. Chemically, they are oligomeric flavonoids. Many are oligomers of catechin and epicatechin and their gallic acid esters. More complex polyphenols, having the same polymeric building block, form the group of tannins.
Procyanidins are members of the proanthocyanidin class of flavonoids. They are oligomeric compounds, formed from catechin and epicatechin molecules. They yield cyanidin when depolymerized under oxidative conditions.
In enzymology, a leucocyanidin oxygenase (EC 1.14.11.19) is an enzyme that catalyzes the chemical reaction
In enzymology, a leucoanthocyanidin reductase (EC 1.17.1.3) (LAR, aka leucocyanidin reductase or LCR) is an enzyme that catalyzes the chemical reaction
Flavonoids are synthesized by the phenylpropanoid metabolic pathway in which the amino acid phenylalanine is used to produce 4-coumaroyl-CoA. This can be combined with malonyl-CoA to yield the true backbone of flavonoids, a group of compounds called chalcones, which contain two phenyl rings. Conjugate ring-closure of chalcones results in the familiar form of flavonoids, the three-ringed structure of a flavone. The metabolic pathway continues through a series of enzymatic modifications to yield flavanones → dihydroflavonols → anthocyanins. Along this pathway, many products can be formed, including the flavonols, flavan-3-ols, proanthocyanidins (tannins) and a host of other various polyphenolics.
Anthocyanins, also called anthocyans, are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical compound that gives flowers a blue color for the first time in his treatise "Die Farben der Blüthen". Food plants rich in anthocyanins include the blueberry, raspberry, black rice, and black soybean, among many others that are red, blue, purple, or black. Some of the colors of autumn leaves are derived from anthocyanins.
The phenolic content in wine refers to the phenolic compounds—natural phenol and polyphenols—in wine, which include a large group of several hundred chemical compounds that affect the taste, color and mouthfeel of wine. These compounds include phenolic acids, stilbenoids, flavonols, dihydroflavonols, anthocyanins, flavanol monomers (catechins) and flavanol polymers (proanthocyanidins). This large group of natural phenols can be broadly separated into two categories, flavonoids and non-flavonoids. Flavonoids include the anthocyanins and tannins which contribute to the color and mouthfeel of the wine. The non-flavonoids include the stilbenoids such as resveratrol and phenolic acids such as benzoic, caffeic and cinnamic acids.
Prodelphinidin is a name for the polymeric tannins composed of gallocatechin. It yields delphinidin during depolymerisation under oxidative conditions.
Taxifolin (5,7,3',4'-flavan-on-ol), also known as dihydroquercetin, belongs to the subclass flavanonols in the flavonoids, which in turn is a class of polyphenols.
Leucopelargonidin is a colorless chemical compound related to leucoanthocyanins. It can be found in Albizia lebbeck, in the fruit of Anacardium occidentale (Cashew), in the fruit of Areca catechu, in the fruit of Hydnocarpus wightiana, in the rhizome of Rumex hymenosepalus, in Zea mays (Corn) and in Ziziphus jujuba.
Procyanidin C2 is a B type proanthocyanidin trimer, a type of condensed tannin.
A type proanthocyanidins are a specific type of proanthocyanidins, which are a class of flavonoid. Proanthocyanidins fall under a wide range of names in the nutritional and scientific vernacular, including oligomeric proanthocyanidins, flavonoids, polyphenols, condensed tannins, and OPCs. Proanthocyanidins were first popularized by French scientist Jacques Masquelier.
Procyanidin B3 is a B type proanthocyanidin. Procyanidin B3 is a catechin dimer.
Procyanidin B6 is a B type proanthocyanidin.
Hedysarum sulphurescens, the yellow sweetvetch or white sweetvetch, is a perennial herb species.
Procyanidin C1 (PCC1) is a B type proanthocyanidin. It is an epicatechin trimer found in grape, unripe apples, and cinnamon.
Condensed tannins are polymers formed by the condensation of flavans. They do not contain sugar residues.
B type proanthocyanidins are a specific type of proanthocyanidin, which are a class of flavanoids. They are oligomers of flavan-3-ols.
