Anthocyanidin
Anthocyanidins are common plant pigments, the
Anthocyanidins are an important subclass of the
At least 31 monomeric anthocyanidins have been properly identified in living organisms, mostly as the core components of anthocyanins. The latter are responsible for the red, purple, blue, or black color of many fruits (like
Classification
3-Deoxyanthocyanidins such as luteolinidin are a class of anthocyanidins lacking an hydroxyl group on carbon 3.
Selected anthocyanidins and their substitutions Anthocyanidin Basic structure (R3 & R4′ = −OH) R3′ R5′ R5 R6 R7 Aurantinidin −H −H −OH −OH −OH Capensinidin −OCH3 −OCH3 −OCH3 −H −OH Cyanidin −OH −H −OH −H −OH Delphinidin −OH −OH −OH −H −OH Europinidin −OCH3 −OH −OCH3 −H −OH Hirsutidin −OCH3 −OCH3 −OH −H −OCH3 Malvidin −OCH3 −OCH3 −OH −H −OH Pelargonidin −H −H −OH −H −OH Peonidin −OCH3 −H −OH −H −OH Petunidin −OH −OCH3 −OH −H −OH Pulchellidin −OH −OH −OCH3 −H −OH Rosinidin −OCH3 −H −OH −H −OCH3
Natural occurrence
Most plant anthocyanins are based on cyanidin (30%), delphinidin (22%), and pelargonidin (18%), respectively. Altogether 20% of the anthocyanins are based on the three common anthocyanidins (peonidin, malvidin, and petunidin) that are methylated.
Around 3%, 3%, and 2% of the anthocyanins or anthocyanidins are respectively labeled as 3-desoxyanthocyanidins, rare methylated anthocyanidins, and 6-hydroxyanthocyanidins, respectively.
In bryophytes, anthocyanins are usually based on 3-desoxyanthocyanidins located in the cell wall. A new anthocyanidin, riccionidin A, has been isolated from the liverwort
Effect of pH
The stability of anthocyanidins is dependent on
References
External links
- Media related to Anthocyanidins at Wikimedia Commons