Phenolic Compounds

Question 1

Define tannins

Answer 1

secondary metabolite non - nitrogenous and phenolic in nature. *forms bonds with proteins and nitrogen containing compounds

Question 2

Define phenolic

Answer 2

heterogeneous group of phytochemicals comprising phenol rings bearing one or more hydroxyl groups

Question 3

Which part of plants are they mostly founds and where in plant cell

Answer 3

mostly in skins and of fruits and veggies. Condensed in the vacuole or cuticle part of cell

Question 4

colour

Answer 4

yellow to dark brown

Question 5

taste

Answer 5

drying or puckering

Question 6

solubility

Answer 6

water soluble, acidic

Question 7

precipitate

Answer 7

gelatine, proteins, pectins and cellulose

Question 8

pharmacological effects

Answer 8

antioxidant, astringent (contraction of skin and other cells), vasoconstrictor, anti sceptic

negative

• irruption
• prevents absorption of nutrience
• long term use ; damage to organs

Question 9

reacts with

Answer 9

• salts; producing blue/black or green/brown

- ammonia and potassium ferricyanides producing deep red colour.

Question 10

types of tannins

Answer 10

hydrolysable (by acids or enzymes), condensed, complex

Question 11

test

Answer 11

• colour reaction with iron, produces green or blue Flourence.
• match stick, wood turns pink
• gelatin test, p. 1%
• gold beaters skin, does it tan skin?