Page 117 - phytochemistry II -pharmD general
P. 117
Plant phenolics
Plant metabolites that possess one or more aromatic moieties bearing one
or more hydroxyl groups.
What is meant by Tannins?
✓ Tannins are found in widely distributed species of plants, and it protects
plant from predators and pests.
✓ Tannins are being used as a significant element for the tanning of animal
hides for their ability to precipitate proteins.
✓ They protect trees from fungi, pathogens, insects, and herbivorous animals
“Tannins are water soluble phenolic compounds with molecular weight of
500 and 3000, capable of precipitating gelatin, alkaloids and other proteins
and provide the typical phenolic reactions”
Tannins Classification
Chemical structure of the complex polyphenols (tannins) that are:
1. Hydrolysable tannin (galloyl and hexahydroxydiphenyl (HHDP)
esters of glucose)
Gallic acid HHDP
116
