This section is from the book "A Text Book Of Materia Medica, Being An Account Of The More Important Crude Drugs Of Vegetable And Animal Origin", by Henry G. Greenish. Also available from Amazon: A Text Book of Materia Medica : Being an Account of the More Important Crude Drugs of Vegetable and Animal Origin.
Elecampane, Inula Helenium, Linne (N.O. Compositoe), is a tall, herbaceous plant, with perennial rhizome, distributed over temperate Europe and Asia. For medicinal use the plant is cultivated in Holland, Thuringia, and Switzerland.
The plant produces a short, thick, fleshy rhizome and large, fleshy roots. Both rhizome and roots are collected when the plants are about three years old and dried, the larger being often sliced longitudinally.
The drug consists of both rhizome and roots. The former is usually cut longitudinally, and occurs in thin, irregularly rounded slices about 4 or 5 cm. in diameter. The roots vary much in size, the smaller being the thickness of a pencil or even less, the larger sometimes exceeding 3 cm. in diameter. They are nearly cylindrical (if entire), tapering very gradually towards the tip, but are seldom quite straight, usually curling irregularly as they dry, especially if they have been sliced.
Fig. 171. - Elecampane root. A, longitudinally cut; B, entire, with portion of the rhizome attached. (.Planchon and Collin).
Both rhizome and root are hard and horny, or, if slightly moist, tough, and are of a dark brownish grey colour externally, whitish or pale brownish internally. They break with a short fracture. The transverse section is more or less uniform in colour and exhibits a number of shining, brown oil-glands scattered over the whole of the surface, both in the bark and in the central portion (wood) which is separated from it by a dark and often very indistinct cambium line. In the wood small, radially elongated groups of vessels occur, but are difficult to discern with a lens. The root has an agreeable aromatic odour and an aromatic, slightly bitter taste.
The student should observe
(a) The horny (not starchy) nature of the drug,
Fig. 172. - Elecampane root. Transverse section, showing the distribution of the oil-glands. Magnified. (Planchon and Collin).
(b) The presence of oil-glands,
(c) The absence of distinct radiate structure in the wood; and. should compare the root with
(i) Belladonna root, which has no oil-glands, and which should possess a starchy fracture, (ii) Dandelion root, which has no oil-glands, a small yellow wood, and thick ringed bark, (iii) Marshmallow root, which has no oil-glands, a radiate structure, and a fibrous, easily separated bark, (iv) Pellitory root, which has oil-glands, but is distinguished by its yellow, radiate wood, distinctive odour and taste.
By distillation with water elecampane root yields from 1 to 2 per cent. of a crystalline mass associated with a little volatile oil. The crystalline mass consists of alantolactone, isoalantolactone (helenin), and alantolic acid, all of which are nearly colourless and crystalline and have but slight odour or taste. Alantol is an oily liquid with a peppermint-like odour found in the distillate. Elecampane root contains also in large quantity, as reserve material, inulin. The roots gathered in the autumn, when they are richest in inulin, contain as much as 45 per cent. of this substance, in the spring about 19 per cent.
Inulin C6H10O5, can be obtained as a white crystalline powder, slightly soluble in cold water but easily soluble in hot water without gelatinising. In the fresh root it is in solution in the cell sap, although only slightly soluble in cold water; when the roots are immersed in alcohol it is slowly deposited in sphero-crystalline masses; in the dry root it occurs in transparent, irregular lumps. It may be distinguished from starch by these characters as well as by the cooled decoction not assuming a blue colour with iodine. It takes the place of starch as a reserve material in many plants belonging to the order Compositoe, and in several belonging to Campantlaceoe, etc. Hydrolysis by means of a dilute mineral acid converts it into levulose.
In the dried root the oil-glands contain crystals of alantolactone which are also to be found in the powder when mounted in dilute nitric acid; the powder also contains irregular black masses of phytomelan which is chiefly found in fruits of Compositae.
Elecampane root has been used in bronchitis and tuberculosis; helenin is an effective antiseptic particularly for the tubercle bacillus.