Morphological information

A biennial or perennial herb attaining a height of 1- 2 m. Leaves rugose, somewhat downy, the radical ones long- stalked and ovate to ovate- lanceolate. The cauline leaves short stalked or sessile, becoming small towards top of stem. Flowers borne in one-side raceme, purple-more or less spotted yellow white. Calyx lobes broadly ovate. Fruits ovoid capsule, exceeding the calyx. Seeds small light and numerous. Flowers and fruits during April and June.

 

History

Digitalis comes from the Latin word "Digitalis" meaning finger, which refers to the finger shape of its corolla. Purpurea is derived from the purple colour of the flowers. Digitalis was used in England as far back as in tenth century in folk medicine and it became a pharmacopoeia drug only in 1650. It became official in France and Germany. Digitalis was specially recommended for cure of dropsy and other diseases in England during Sixteenth century. However, the use of digitalis in medicine is found in "great herbal" published by Peter Treveris in 1526. Fuchs (1542), a professor of medicine in Germany, described digitalis as emetic and purgative. Andre Cesalpine was probably the first to suggest the effect of digitalis on circulation of blood in the century. By 1961, when it was adopted in British Pharmacopeia, it was recommended for treatment of epilepsy as a sedative and as a treatment of tuberculosis. William Salman, a noted British physician, recorded it as a valuable cure for dropsy. However, French Physician Salarne based on some faulty experiments, published a paper in 1748, which declared digitalis as a poison. This resulted into complete ban on the drug in Europe. However, as a result of ten years exhaustive study by the noted physician William Withering, the drug was useful in number of patients. As a result of careful experimentation, he concluded that digitalis has a definite effect on heart and blood circulation and can be used for treatment of heart diseases. It was on the basis of this publication that digitalis was again adopted in pharmacopoeia in Europe and USA and has been a drug of choice for various heart diseases since 19th century.

 

Parts        : Leaves.

Status      : Low risk

Phytochemistry

Two new glucuronoxylosides of luteolin isolated from leaves but not identified (C.R.Acad.Sci. Ser D.1969, 269, 16754; Chem. Abstr. 1970, 72, 63595 e); digitolutein, digitopurpone, phomarine and isochrysophenol found in leaves (J.Chem. Soc.C.1971, 2007 ); saponification of methyl esters of triglycerides fraction yielded C10C14C16 and C18 saturated acids, C16:1 and C18:1 monosaturated,C18:2 diunsaturated and C18:3 triunsaturated adds (J. Pharm. Pharmacol.1972, 24, Suppl.168); cycloeucalenol, obtusifbliol, 24 methyleneolphenol, 24- methylenecholesterol isolated from flower's and seeds (J Pharm. Pharmocol. 1972, 24, 227; ibid.1973, 25, 156) in addition, cycloartenol, 24 methylene- cycloartenol, 24 methyllophenol and 24- ethyllophenol isolated from seeds (J. Pharm. Pharmocol. 1972, 24,227); glucose was major carbohydrate in leaves and stems whereas fructose predominated in inflorescence at various stages of plant growth (Phytochemistry 1973, 12, 2331) a bisdesmosidic 22- hydroxyfurostanol glycoside- purpureagitoside from leaves characterized (Chem.Ber.1974, 107, 2828); apigenin, dinatin, chryoseriol and nepetin from leaves (Planta Med.1977, 32, 347).

Agrocultivation

Digitalis purpurea is propagated through seeds. A nursery is raised and seedlings are transplanted when the plants become 4- 6 weeks old. Seedling can be directly sown in March- April, or in October November in autumn. Seeds are planted in rows at the distance of 4- 5 cm and thinned out at a distance of 20- 30 cm, when they are 5- 5.7 cm high. For raising nursery, seeds are generally planted in hot houses in February and then transferred to field in March- April. Seedlings are planted at a distance of 20- 30 cm in rows, which are 45 cm apart

 

Medicinal

Leaves are used for cardiac stimulant, diuretic; useful in renal obstruction and dropsy; tincture digitalis, an official pharmaceutical preparation from the leaves of both D. lanata and D. purpurea is very useful for the treatment of congestive heart failure associated with or without low or high blood pressure, fibrillating flutter, tachycardia and valvular defects.

 

---