Doc:FL63AC
From Metabolomics.JP
(Difference between revisions)
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and [[FL63ACNS0001|(+)-Catechin]] and its stereoisomer | and [[FL63ACNS0001|(+)-Catechin]] and its stereoisomer | ||
[[FL63ACNS0002|(-)-Epicatechin]] are naturally abundant. Less abundant are [[FL63ACNS0004|(-)-Catechin]] and [[FL63ACNS0003|(+)-Epicatechin]]. | [[FL63ACNS0002|(-)-Epicatechin]] are naturally abundant. Less abundant are [[FL63ACNS0004|(-)-Catechin]] and [[FL63ACNS0003|(+)-Epicatechin]]. | ||
| − | + | * afzelechin ... catechin minus 1 hydroxyl group in ring B | |
| + | * gallocatechin ... catechin plus 1 hydroxyl group in ring B | ||
| | | | ||
いわゆるカテキン類とは、[[:Category:FL63|Flavan 3-ol]]の下にあるグループを指します。C2, C3位にある不斉炭素によって4つの異性体が作られますが、自然界に豊富なのは [[FL63ACNS0001|(+)-カテキン]] とその立体異性体である | いわゆるカテキン類とは、[[:Category:FL63|Flavan 3-ol]]の下にあるグループを指します。C2, C3位にある不斉炭素によって4つの異性体が作られますが、自然界に豊富なのは [[FL63ACNS0001|(+)-カテキン]] とその立体異性体である | ||
[[FL63ACNS0002|(-)-エピカテキン]] です。 [[FL63ACNS0004|(-)-カテキン]] と [[FL63ACNS0003|(+)-エピカテキン]] は自然界にあまりみられません。 | [[FL63ACNS0002|(-)-エピカテキン]] です。 [[FL63ACNS0004|(-)-カテキン]] と [[FL63ACNS0003|(+)-エピカテキン]] は自然界にあまりみられません。 | ||
| − | + | * アフゼレキン ... カテキンのB環から水酸基を一つ除いたもの | |
| + | * ガロカテキン ... カテキンのB環に水酸基を一つ追加したもの | ||
}} | }} | ||
Revision as of 11:39, 19 August 2010
Catechins refer to a subgroup of flavan 3-ol derivatives (FL63AC). The two chiral center at C2 and C3 of the flavan 3-ols produces 4 isomers, and (+)-Catechin and its stereoisomer (-)-Epicatechin are naturally abundant. Less abundant are (-)-Catechin and (+)-Epicatechin.
- afzelechin ... catechin minus 1 hydroxyl group in ring B
- gallocatechin ... catechin plus 1 hydroxyl group in ring B
| Structure | 
|
|
|
|
|---|---|---|---|---|
| Name | (+)-Catechin or D-Catechin |
(-)-Epicatechin or L-Epicatechin |
ent-Catechin or (-)-Catechin |
ent-Epicatechin or (+)-Epicatechin |
| B-ring stereo | ↓ | ↓ | ↑ | ↑ |
| 3-Hydroxyl stereo | ↑ | ↓ | ↓ | ↑ |
| Gallocatechins | (+)-Gallocatechin | (-)-Epigallocatechin | (-)-Gallocatechin |
Among the stereoisomers, the bioavailability in human follows the order:
| (-)-epicatechin | > | (+)-catechin | = | (+)-epicatechin | > | (-)-catechin |
The circulation level of (-)-epicatechin is 6 times higher than that of (-)-catechin. Naturally abundant species are more bioavailable than less abundant ones.
