Tannins 1 Flashcards
2 Classification of tannins
True Tannin
Psuedotannin
Test used to identify the classification of tannin
Goldbeater skin test
What are the 2 types of True Tannins
Hydrolysable Tannins
Non-Hydrolysable Tannins
What are hydrolysable tannins?
They are ester of sugars and phenolic acid molecules
They are substances used to heat up hydrolysable tannins
Hydrochloric Acid or Sulphuric acid
They are the result of heating up hydrolysable tannins
Gallic or Ellagic Acid
Historically, tannin containing drugs are related to their ______________ or their ability to transform fresh hides into ___________ Imputrescible leather
Tanning Property
Imputrescible
Positive color result for true tannins
Brown or Black
It is where where goldbeater’s skin is soaked in order to test
2% Hydrochloric Acid
Goadbeater’s skin is a membrane prepared from __________________
Intestine of Ox
Ox intestine that is used in goldbeater’s test behaves similarly to an _______________
Untanned Hide
Give 3 sources of tannins and their scientific name
Myrobalan (Terminalia chebula Combretaceae )
Bahera (Terminalia belerica Combretaceae)
Witch Hazel (hamamelidaceae)
Gallic Acid Contains _____________ and can be found in plants such as _________________
Gallotannins
Rhubarb
Gall
Clove
Ellagic Acid contains ______________ and can be found in plants such as _________________
Ellagitannins
Pomegranate
Eucalyptus
Color produced by hydrolysable tannin solution with ferric chloride
Blue
Gallic acid and Ellagic acid are types of ________
Phenolic Acid
What are the physical properties of Tannins?
Dark Brown to Light Brown
Puckering Taste
Non-Crystalline
Soluble in:
Water
Alcohol
Diluted Alkali solution
Acetone
Result of Tannins reaction with potassium ferricyanide and ammonia
Deep red color
Tannins reaction that causes precipitation
Salt of copper, lead, tin & potassium dichromate or 1% chromic acid solutions
Result when tannins react with proteins, alkaloids and heavy metals
Precipitation
