Synonyms: Kattha, Cutch, Catechu.
Biological Source: Black catechu or cutch is an aqueous extract of the heartwood of Acacia catechu Willdenow, concentrated by boiling.
Family: Leguminosae.
Geographical Source: The plants used for preparation of catechu are grown in Myanmar and India.
Description:
Colour: Dull brownish to black.
Odour: Odourless.
Taste: Astringent and subsequently sweet.
Size: Near about 2.0 cm × 5.0 cm.
Shape: Cube like or brick shaped pieces.
Solubility: A brown magma forms with cold water but with boiling water it dissolves entirely and crystalline sediment is deposited upon cooling.
Chemical Constituents:
The chief constituents are catechutannic acid (25-33%) and acacatechin (10-12%). Other
constituents are catechu red, gum, quercitin and quercitrin.
Chemical Test:
1. When drug is treated with vanillin and hydrochloric acid, it produces pink or red
colour due to the presence of catechin.
2. Add ferric ammonium sulphate to the aqueous solution of drug, green colour
develops which turns to purple by the addition of sodium hydroxide.
3. To the aqueous solution of drug, add lime water brown colour produced which turns
into reddish precipitate after some time.
Uses:
Catechu is used as an astringent, cooling and digestive action whereas cutch is not used
medicinally. It is used for dyeing and tanning purposes like fishing nets etc.