Habitat: Cultivated in many parts of India.
English: Indigo.Ayurvedic: Nilikaa, Nilaa, Nila, Nili, Nilini, Nilapushpa, Ranjani, Shaaradi, Tutthaa.Unani: Habb-ul-Neel.Siddha/Tamil: Nili, Averi, Asidai, Attipurashadam.Action: Plant—antiseptic, hepato- protective, hypoglycaemic, nervine tonic. Used in enlargement of liver and spleen, skin diseases, leucoder- ma, burns, ulcers, piles, nervous disorders, epilepsy, asthma, lumbago, gout. Leaf—anti-inflammatory. Used in blennorrhagia. Root— diuretic. Used in hepatitis. Root and stem—laxative, expectorant, febrifuge, anticephalalgic, anti- tumour, anthelmintic, promote growth of hair.
The Ayurvedic Pharmacopoeia of India recommends the use of dried whole plant in phobia, delusion and disturbed mental state.Indicine (5-15 mg/g, dry basis) and the flavonoids, apigenin, kaempferol, luteolin and quercetin are present in various plant parts, maximum in the leaves and minimum in the roots (however quercetin was minimum in leaves). The presence of coumarins, cardiac glycosides, saponins and tannins is also reported.Alcoholic extract of the aerial parts showed hepatoprotective activity in experimental animals against CCl4- induced hepatic injury. The extract increased bile flow and liver weight in rats. The alcoholic extract also exhibited hypoglycaemic activity in rats.The plant is used in the treatment of endogenous depression. It contains appreciable amounts of conjugated in- doxyl (indican). The use of indigo and its constituents, indirubin and indigotin, prevents allergic contact dermatitis. The 8 weeks old tissues in culture contain maximum histamine content (5.0 mg/g dry weight).Dosage: Dried leaf—50-100 g for decoction; root—48 g for decoction (API Vol. II); whole plant—10-20 g for decoction. (API Vol. III.)