Study Set Content:
They are precipitated by salts of _____ and by strong aqueous Potassium dichromate solution
Copper, Lead and Tin
Tannins precipitate proteins from solutions and can combine with proteins rendering them resistant to
proteolytic enzymes
When applied to living tissues, this action is known as
astringent
HAMAMELIS hamamelis leaf or , is the dried leaf of
witch hazel leaves ,Hamamelis virginiana (Hamamelidaceae)
Constituents:
hamamelitannin, hexose sugar, volatile oil, galic acid, a bitter principle, calcium oxalate
Use:
astringent and incorporated in hemorrhoidal products
NUTGALL is the excrescence obtained from the young twigs of
Quercus infectoria (Fam. Fagaceae)
Constituents
tannic acid, gallic acid, ellagic acid, starch, resin
Use:
used in tanning and dyeing industry astringent
is a mixture of esters of gallic acid with glucose whose exact composition varies according to its source
gallotannic acid or tannin,
occurs as an amorphous powder, glistening scales or spongy masses that are light brown to yellowish white. Having a faint odor
TANNIC ACID
Tannic acid It has a strong astringent taste, soluble in (blank) and insoluble in ((blank)
water, alcohol, and acetone,ether, chloroform, and benzin
Use:
o Astringent
o Used in the treatment of bed sores and minor ulcerations
o Employed in cases of alakaloidal poisoning
General use of Tannins
• Anti-diarrhea
• Antibacterial
• Antidote
• Haemostatic
• Mild diuretic
• Leather industry
• Astringent
• stomachic
sources are used as cortisone precurso
diosgenin
present in cambium sap of pine trees
Coniferin-
-present in clove oil
eugenol
by product of the pulp industry
lignin
