Valerian Root; F. Racine de Valériane; G. Baldrianwurzel.
Botanical Origin—Valeriana officinalis L., an herbaceous perennial plant, growing throughout Europe from Spain to Iceland, the North Cape and the Crimea, and extending over Northern Asia to the coasts of Manchuria. The plant is found in plains and uplands, ascending even in Sweden to 1200 feet above the sea-level.
In England, valerian is cultivated in many villages[1394] near Chesterfield in Derbyshire, the wild plant which occurs in the neighbourhood not being sufficiently plentiful to supply the demand.
In Vermont, New Hampshire and New York, as well as in Holland, the plant is grown to some extent, but by far the largest supply would appear to be grown in the environs of the German town Cölleda, not far from Leipzig.
Valerian is propagated by separating the young plants which are developed at the end of runners emitted from the rootstock.
The wild plant, according to the situation it inhabits, exhibits several divergent forms. Among eight or more varieties noticed by botanists,[1395] we may especially distinguish α. major with a comparatively tall stem and all the leaves toothed, β. minor (V. angustifolia Tausch) with entire or slightly dentate leaves, and also V. sambucifolia Mikan, having only 4 or 5 pairs of leaflets.
History—The plant which the Greeks and Romans called Φοῦ or Phu, and which Dioscorides and Pliny describe as a sort of wild nard, is usually held to be some species of valerian.[1396]
The word Valeriana is not found in the classical authors. We first meet with it in the 9th or 10th century, at which period and for long afterwards, it was used as synonymous with Phu or Fu.
Thus in the writings of Isaac Judæus[1397] occurs the following:—“Fu id est valeriana, melior rubea et tenuis et quæ venit de Armenia et est diversa in sua complexione....”
Constantinus Africanus[1398]—“Fu, id est valeriana. Naturam habet sicut spica nardi....”
The word Valeriane occurs in the recipes of the Anglo-Saxon leeches written as early as the 11th century.[1399] Valeriana, Amantilla and Fu are used as synonymous in the Alphita, a mediæval vocabulary of the school of Salernum.[1400]
Saladinus[1401] of Ascoli directs (circa a.d. 1450) the collection in the month of August of “radices fu id est valerianæ.”
Valerian was anciently called in English Setwall, a name properly applied to Zedoary; and the root was so much valued for its medicinal virtues, that as Gerarde[1402] (1567) remarks, the poorer classes in the north of England esteemed “no broths, pottage, or physicall meats” to be worth anything without it. Its odour, now considered intolerable, was not so regarded in the 16th century, when it was absolutely the custom to lay the root among clothes as a perfume[1403] in the same way as those of Valeriana celtica L. and the Himalayan valerians are still used in the East.
Some of the names applied to valerian in Northern and Central Europe are remarkable. Thus in Scandinavia we find Velandsrot, Velamsrot, Vandelrot (Swedish); Vendelród, Venderód, Vendingsród (Norwegian); and Velandsurt (Danish)—names all signifying Vandels’ root.[1404] Valerian is also called in Danish Danmarks græs. Among the German-speaking population of Switzerland, a similar word to the last, namely Tannmark, is applied to valerian. The Denemarcha mentioned by St. Hildegard,[1405] about a.d. 1160, is the same. These names seem to point to some connexion with Northern Europe which we are wholly unable to explain.
Pentz, a pharmaceutical assistant at Pyrmont, was the first, in 1829, to draw attention to the acid reaction of the distilled water of valerian. Another German assistant, Grote, at Verden, showed in 1831 that the acidity was by no means due to acetic acid, but to a peculiar kind of acid. The latter was identified in 1843 by Dumas with the acid artificially obtained from amylic alcohol and that extracted in 1817 by Chevreul from the fat of dolphins.
Description—The valerian root of the shops consists of an upright rhizome of the thickness of the little finger, emitting a few short horizontal branches, besides numerous slender rootlets.[1406] The rhizome is naturally very short, and is rendered still more so by the practice of cutting it in order to facilitate drying. The rootlets, which are generally 3 to 4 inches long, attain ⅒ of an inch in diameter, tapering and dividing into slender fibres towards their extremities. They are shrivelled, very brittle, and, as well as the rhizome, of a dull, earthy brown. When broken transversely, they display a dark epidermis, forming part of a thick white bark which surrounds a slender woody column. The interior of the rhizome is compact, firm and horny, but when old becomes hollow, a portion of the tissue remaining however in the form of transverse septa.
The drug has a peculiar, somewhat terebinthinous and camphor-like odour, and a bitterish, aromatic taste. The root when just taken from the ground has no distinctive smell, but acquires its characteristic odour as it dries.
Microscopic Structure[1407]—In the rhizome as well as in the rootlets, the cortical part is separated from the central column by a dark cambial zone; the medullary rays are not distinctly obvious. In old rootstocks, sclerenchymatous cells are met with in the cortical tissue.
The parenchyme of the drug is loaded with small starch granules, brownish grains of tannic matter and drops of essential oil. Numerous oil ducts are met with in the outer layer of the tissue.
Chemical Composition—Volatile oil is contained in the dry root to the extent of ½ to 2 per cent., yet on an average appears scarcely to exceed ⁴/₅ per cent. This variation in quantity is partly explained by the influence of locality, a dry, stony soil yielding a root richer in oil than one that is moist and fertile. In the latter the plant may be distinguished as the variety sambucifolia, which has a less vigorous root, devoid of runners.
Schoonbroodt[1408] has shown that the most important influence is the recent condition of the root. He states that if the root is submitted to distillation when perfectly fresh, it yields a neutral water and a large quantity of essential oil. The latter has but a very faint odour, but by exposure to the air it slowly acidifies, especially if a little alkali is added, and acquires a strong smell. Valerianic Acid which is thus formed amounts to 6 per mille of the fresh root. The dried root yields a distillate of decided valerian odour, containing valerianic acid, but in proportion not exceeding 4 per mille of the root calculated as fresh.
The oil of valerian is of a very peculiar yellowish or brownish, sometimes even almost a little greenish hue, and possessing the characteristic odour of the drug. We found it to deviate the plane of polarization from 11° to 13° to the left when examined by Wild’s Polaristrobometer in a column of 50 millimetres. By submitting it to fractional distillation we noticed[1409] that it affords a magnificent blue fraction. A superb violet or blue colour is produced if one drop of the crude oil dissolved in about 20 drops of bisulphide of carbon is mixed with 1 drop of nitric acid 1·20 sp. gr. Other colorations are produced if bromine or concentrated sulphuric acid are used;[1410] even the tincture of valerian displays similar reactions.
Bruylants (1878) has isolated from oil of valerian—1st. A hydrocarbon, C₁₀H₁₆, boiling at 157° C., yielding a crystallized compound with HCl. 2nd. The liquid compound C₁₀H₁₈O, which by means of chromic acid affords common camphor and formic, acetic and valerianic acids, which are met with in old valerian root, owing no doubt to the slow oxidation of the compound C₁₀H₁₈O. 3rd. There is also present a crystallizable compound of the same composition, which is probably identical with the camphor of Dryobalanops aromatica (see our article on Camphora). It would appear that this substance is of alcoholic nature, being combined in the root with the 3 organic acids mentioned under 2nd. On distilling, these compound ethers are resolved partly into the alcohol C₁₀H₁₈O (borneol) and the acids. This decomposition is fully performed, if the root is macerated with alkaline water, and then, on distilling, a slight excess of sulphuric acid is added. 4th. At about 300° a greenish portion is coming over, which can be obtained colourless by again rectifying it. This oil assumes intense colorations if it is shaken with concentrated mineral acids; it becomes blue by distilling it over potash.
Valerianic acid as afforded by the root is not agreeing with normal valerianic acid. It is, more exactly, isovalerianic acid, or isopropyl-acetic acid: (CH₃)₂CH·CH₂COOH, which is produced by Valeriana as well as by Archangelica officinalis and Viburnum Opulus. The same acid also may be obtained from the fat of Dolphinus globiceps.
After the root has been submitted to the distillation of the oil, there is found a strongly acid residue containing malic acid, resin, and sugar,—the last capable, according to Schoonbroodt, of reducing cupric oxide.
Uses—Valerian is employed as a stimulant and antispasmodic.
Substitutes—In the London market there has been offered “Kesso” the root of Patrinia scabiosaefolia Link,[1411] a Japanese herb of the order Valerianaceæ. This drug consists of a very short rootstock giving off a large number of rootlets about 5 inches long and ⅒ of an inch in diameter. By the absence of a well-marked upright rhizome in this Japanese Valerian it is widely differing from our Valerian, although at first sight it agrees to some extent with it. As to the odour and taste we find Kesso almost identical with true Valerian.
The less aromatic and now disused root of Valeriana Phu L. consists of a thicker rhizome which lies in the earth obliquely; it is less closely annulated and rooted at the bottom only. It resembles by no means true Valerian.