What’s a phenolic compound?
A secondary product that contains a phenol group
- a hydroxyl functional group on an aromatic ring.
Phenolics are a chemically diverse group: many
different properties and functions.
Biosynthesis of phenolics
Shikimic acid pathway is most common in plants. Converts simple
carbohydrates into aromatic amino acids. Not present in animals.
Most plant phenolics are derived from cinnamic acid
formed from phenylalanine by phenylalanine ammonia lyase
PAL activity is inducible: fungal infection, low nutrient levels, high light
Major types of phenolics
1. Simple phenolics - e.g. coumarins
2. Lignin - 2nd most abundant compound in plants
3. Flavonoids - two aromatic rings, 2 pathways
4. Condensed tannins
5. Hydrolyzable tannins
made of phenolic acids and sugars
smaller molecules than condensed tannins