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Proanthocyanidin B4
Procyanidin B4 is a B type proanthocyanidin. Procyanidin-B4 is a catechin-(4α→8)-epicatechin dimer. It is found in the litchi pericarp, in grape seeds, and, along with 4-cis-isomer of procyanidin B4, in beer. See also *Phenolic content in wine
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 ...
References Procyanidin dimers ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
B Type Proanthocyanidin
B type proanthocyanidins are a specific type of proanthocyanidin, which are a class of flavanoids. They are oligomers of flavan-3-ols. Dimeric B type proanthocyanidins These molecules have the molecular formula C30H26O12 (molar mass : 578.52 g/mol, exact mass : 578.142426). Molecules with 4→8 bonds The 4-8 bond can be in the alpha or in the beta position. * Procyanidin B1 or epicatechin-(4β→8)-catechin * Procyanidin B2 or (−)-epicatechin-(4β→8)-(−)-epicatechin * Procyanidin B3 or catechin-(4α→8)-catechin * Procyanidin B4 or catechin-(4α→8)-epicatechin Molecules with 4→6 bonds * Procyanidin B5 or epicatechin-(4β→6)-epicatechin * Procyanidin B6 or catechin-(4α→6)-catechin * Procyanidin B8 or catechin-(4α→6)-epicatechin Chemistry B-type procyanidin (catechin dimer) can be converted to A-type procyanidin by radical oxidation. Dimeric proanthocyanidins can also be synthesized with procyanidin-rich grape seed extracts reacted with flavan-3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catechin
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. The name of the catechin chemical family derives from '' catechu'', which is the tannic juice or boiled extract of ''Mimosa catechu'' ('' Acacia catechu'' L.f). Chemistry Catechin possesses two benzene rings (called the A- and B-rings) and a dihydropyran heterocycle (the C-ring) with a hydroxyl group on carbon 3. The A-ring is similar to a resorcinol moiety while the B-ring is similar to a catechol moiety. There are two chiral centers on the molecule on carbons 2 and 3. Therefore, it has four diastereoisomers. Two of the isomers are in trans configuration and are called ''catechin'' and the other two are in cis configuration and are called ''epicatechin''. The most common catechin isomer is (+)-catechin. The other stereoisomer is (-)-catechin or ''ent''-catechin. The most common epicatechin isomer is (-)-epic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epicatechin
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. The name of the catechin chemical family derives from ''catechu'', which is the tannic juice or boiled extract of ''Mimosa catechu'' (''Acacia catechu'' L.f). Chemistry Catechin possesses two benzene rings (called the A- and B-rings) and a dihydropyran heterocycle (the C-ring) with a hydroxyl group on carbon 3. The A-ring is similar to a resorcinol moiety while the B-ring is similar to a catechol moiety. There are two chiral centers on the molecule on carbons 2 and 3. Therefore, it has four diastereoisomers. Two of the isomers are in trans configuration and are called ''catechin'' and the other two are in cis configuration and are called ''epicatechin''. The most common catechin isomer is (+)-catechin. The other stereoisomer is (-)-catechin or ''ent''-catechin. The most common epicatechin isomer is (-)-epicatechin (also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenolic Content In Wine
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. Origin of the phenolic compounds The natural phenols are not evenly distributed within the fruit. Phenolic acids are largely present in the pulp, anthocyanins and stilbenoids in the skin, and other phenols (catechins, proanthocyanidins and flavon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
