संस्कृत नाम- वचा
Botanical name - Acorus calamus
Description - Perennial, erect, aromatic herb, common on river banks and marshes, ascending to 3000 m; rhizome cylindrical or slightly compressed, about 2.5 cm in diameter, much-branched, externally light brown or pinkis'h brown but white and spongy within; leaves distichous, large, 1-2 m in length, base equitant, margin waved; spadix sessile, cylindric, densely flowered, not completely enclosed by spathe, spathe 15-75 cm in length, narrow, leaf-like; flowers small, bisexual; berries few-seeded; seeds oblong, albuminous.
Chemical_Constituents- Rhizome, roots and leaves contain volatile oil, where asarone and beta-asarone are the important constituents. Presence of small quantities of palmitic, heptylic and butyric acids, asarinaldehyde, calamol, calamone and azulene are reported. Sesquiterpene ketones like acorone, calorene, calacone, calacorene, acorenone, acolamone, isoacolamone, epishyobunone, shyobunone, isoshyobunone and acoragermacrone and alcohols like isocalamendiol and y-resicalamendiol are present. Hydrocar-bons present in the oil are elemene, caryophyllene, calanene, cadalene and humulene. Rhizome also contains phenyl indane derivative. Rhizome oil also contains phenylpropane derivatives. Also from Lexicon --Dry rhizome :1.5-3.5% of a yellow aromatic volatile oil-calamus oil; the oil contains beta-asarone, small quantities of sesquiterpenes and sesquiterpenes alcohols; Rhizome : also contains choline (0.26%), flavone, acoradin, 2,4,5-tri-MeO-benzaldehyde, 2,5-di-MeO-benzoquinone, galangin, calameone, acolamone, isoacolamone, epoxyisoacoragermacrone; Aerial parts : lutcolin-6,8-c-diglucoside; chemical constituents vary in ecotypes and polyploides.
Uses - Calamus acts as a carminative that is it relieves flatulence and feeling of overfullness of stomach, and increases appetite. It is considered a household remedy for flatulent colic. Due to its essential oil contents, it acts as an expectorant i.e. it promotes flow of bronchial secretions and is useful in asthma. It also contains tannins, and is therefore, useful in diarrhoea and dysentery. Calamus also acts as emetic and larger doses can cause violent vomiting. The leaves and rhizomes are also used for flavoring drinks, for perfumery and for preparing insecticides. Its powered roots are used as vermifuge. "The oil from the rhizomes is a good nerve-stimulant and the essential-oil-free alcoholic extract shows marked sedative and analgesic (i.e. pain-relieving) properties; these justify its use in mental diseases. The antibacterial activity of the rhizomes has recently been shown experimentally. It is used in speech defects, in epilepsy, and as a laxative for children and as an emetic.