San: Vaca, Ugragandha, Bhadra;
Hin: Bacc, Gorbacc;
Ben: Bach; Mal:Vayampu;
Tel: Vasa Vadaja
Importance: The sweet flag is an important medhya drug, capable of improving memory power and intellect. It is used in vitiated conditions of vata and kapha, stomatopathy, hoarseness, colic, flatulence, dyspepsia, helminthiasis, amenorrhoea, dismenorrhoea, nephropathy, calculi, strangury, cough, bronchitis, odontalgia, pectoralgia, hepatodynia, otalgia, inflammations, gout, epilepsy, delirium, amentia, convulsions, depression and other mental disorders, tumours, dysentery, hyperdipsia, haemorrhoids, intermittent fevers, skin diseases, numbness and general debility. It is reportedly useful in improving digestion, clearing speech and curing diarrhoea, dysentery, abdominal obstruction and colic. It is also useful in infantile fever, cough bronchitis and asthma. The drug is reported to cure hysteria, insanity and chronic rheumatic complaints. The rhizome is an ingredient of preparations like Vacaditaila, Ayaskrti, Kompancadi gulika, Valiya rasnadi kashaya, etc.
Distribution: The plant is a native of Europe. It is distributed throughout the tropics and subtropics, especially in India and Sri Lanka. It is found in marshes, wild or cultivated, ascending the Himalayas upto 1800m in Sikkim. It is plentiful in marshy tracts of Kashmir and Sirmoor, in Manipur and Naga Hills.
Botany: Acorus calamus Linn. belonging to the family Araceae is a semi -aquatic rhizomatous perennial herb. Rhizome is creeping, much branched, cylindrical or slightly compressed, light brown or pinkish brown externally, white and spongy within. Leaves are bright green, distichous, ensiform, base equitant, thickened in the middle and with wavy margins. Flowers are light brown and densely packed in sessile cylindric spadix. Fruits are oblong, turbinate berries with a pyramidal top. Seeds are few and pendant from the apex of the cells (Warrier et al, 1993).
Another species belonging to the genus Acorus is A. gramineus Soland, the roots of which are used in tonic, antiseptics and insecticidal preparations (Chopra et al, 1956).
Agrotechnology: Acorus is a hardy plant found growing from tropical to subtropical climates. It needs a good and well distributed rainfall throughout the year. It needs ample sunlight during the growth period as well as after harvest for drying the rhizomes. It may be cultivated in any good but fairly moist soil. It is usually grown in areas where paddy can be grown. It comes up well in clayey soils and light alluvial soils of river bank. The field is laid out and prepared exactly as for rice, irrigated sufficiently and after ploughing twice, watered heavily and again ploughed in the puddle. Sprouted rhizome pieces are used for planting and pressed into the mud at a depth of about 5cm at a spacing of 30x30cm. The rhizomes are planted in such a way that the plants in the second row comes in between the plants of the first row and not opposite to them. FYM is to be applied at 25t/ha. Fertilisers are applied at 25:50:60 kg N:P2O5:K2O/ha/yr. Whole of FYM and 1/3 of N, P2O5 and K2O are to be added in the field during March – April as a basal dose. The remaining 2/3 of nutrients is to be given in two equal split doses at 4 months and 8 months after planting. The field is to be regularly irrigated. About 5 cm of standing water is to be maintained in the field in the beginning. Later, it is to be increased to 10 cm as the plant grows. The field is to be regularly weeded. About 8 weedings are to be carried out in all. At each weeding the plants are pressed into the soil. The plant is attacked by mealy bugs. Both shoot and root mealy bugs can be controlled by spraying the shoot and drenching the roots of grown up plants with 10 ml Methyl parathion or 15ml Oxydemeton methyl or 20ml Quinalphos in 10 litres of water. The crop is ready for harvest at the end of first year. The field is to be dried partially so that sufficient moisture is left in the soil to facilitate deep digging. The leaves start turning yellow and dry, indicating maturity. The rhizome will be at a depth of 60cm and having about 30-60cm spread. Therefore, harvesting is to be done carefully. The rhizomes are to be cut into 5-7.5cm long pieces and all the fibrous roots are to be removed. Yield of rhizome is about 10t/ha (Farooqi et al, 1991).
Properties and Activity:Rhizomes, roots and leaves yield essential oil. The important constituents of the Indian oil are asarone and its -isomer. Other constituents are and -pinene, myrcene, camphene, p-cymene, camphor and linalool, sesquiterpenic ketones like asarone, calamone, calacone, acolamone, iso-acolamone, acoragermacrone, epishyobunone, shyobunone and iso- shyobunone. Alcohol present is preisocalamendiol. Sesquiterpene hydrocarbons like elemene, elemane and calarene are also present. Tricyclic sesquiterpenes present are caryophyllene, humulene, guaiene, S-guaizulene, arcurcumene, -cadinene, cadinane, calamenene, calacorene, dihydrocalacorene(calamenene), cadalene and selinene. Roots yield acoric acid as a main constituent in addition to choline. Plant also yields a flavone diglycoside- luteolin 6,8-C-diglucoside.
-asarone is the ma jor constituent of essential oil from rhizome (Dandiya et al, 1958,1959; Raquibuddoula, 1967).
Rhizome is insecticidal, pisicidal, spasmolytic, hypothermic, CNS active and analgesic. Essential oil is anticonvulsant. Rhizome is acrid, bitter, thermogenic, aromatic, intellect promoting, emetic, laxative, carminative, stomachic, anthelmintic, emmenagogue, diuretic, alexeteric, expectorant, anodyne, antispasmodic, aphrodisiac, antiinflammatory, sudorific, antipyretic, sialagogue, insecticidal, tranquillizer, sedative, analgesic, antithermic, antiasthmatic, hypotensive, respiratory depressant, aperitive and tonic.