what is the action of concentrated sulphuric acid on curcuma
Answers
Answer:
The chief constituents of turmeric are curcumin, a yellow crystalline body, and about 5 per cent. of a volatile oil. The rhizome also contains starch and resin, some of the starch being gelatinised owing to the method in which the drug is prepared for market. Curcumin is a yellow crystalline substance which dissolves in alcohol to form a deep yellow solution, alkalies changing the colour to reddish-brown; concentrated sulphuric acid, or better, a mixture of that reagent with alcohol, produces with tissues containing curcumin a deep crimson colouration, a reaction which is often useful in detecting the powdered drug. Boric acid changes it to reddish-brown, which, on the addition of alkalies, becomes greenish-blue.
Answer:
Curcumin is a yellow crystalline substance which dissolves in alcohol to form a deep yellow solution, alkalies changing the colour to reddish-brown; concentrated sulphuric acid, or better, a mixture of that reagent with alcohol, produces with tissues containing curcumin a deep crimson colouration, a reaction which is often useful in detecting the powdered drug. Boric acid changes it to reddish-brown, which, on the addition of alkalies, becomes greenish-blue.