Library   

 

                           

VIOLA - VIOLET
(1) United States Dispensatory 1926
(2) King's American Dispensatory. 1898
Compiled by Ivor Hughes.

(1) Viola, Violet.� The genus Viola (Fam. Violaceae)  includes numerous species, many, perhaps all, of which are possessed of analogous medicinal properties. Viola tricolor L., the Heart's-ease, Pansy, or Johnny-jump-up of the gardens, was formerly recognized by the U. S. Pharmacopoeia; while V. odorata L., and V. pedata L., have held places in both the British and the United States Pharmacopoeias. 

V. odorata L. Sweet Violet, Violette, Violette odorante, Fr.; Wohlriechendes Veilehen, Veilchen, G.; Violetta, It.; Violeta, Sp.

This is the common violet of Europe and also the parent of the florists' violets. It resembles very closely the American blue violet, V. oucullata Ait., from which, however, it is at once distinguished by its greater fragrance. It is the sweet violet of our gardens. V. pedata L., or Bird's Foot Violet is an indigenous, stemless Violet, characterized by its large blue or variegated beardless flowers, and its deeply three- to five-divided, pointed pedate leaves. . The flowers of V. odorata yield their odor and their slightly bitter taste .to boiling water. Their infusion affords a delicate test for acids and alkalies, being reddened by the former and rendered green by the latter. Their odor is destroyed by desiccation, and the degree to which they retain their fine color depends upon the care used in collecting and drying them. 

They should be gathered before being fully blown, deprived of their calyx, and rapidly dried, either in a heated room or by exposing them to a current of very dry air. The flowers of other species are often mingled with them, and, if of the same color, are equally useful as a chemical test. In the root, leaves, flowers, and seeds of Viola odorata, Boullay discovered an alkaloid, violine, allied to emetine, but possessing distinct properties. It exists in the plant combined with malic acid. Orfila asserts that it is exceedingly active and even poisonous. Linde, however (Chem. Abstr., 1910, xiii, 2963) says that the amount of alkaloid in the violet roots is so small that one can scarcely attribute any toxic effect of these roots to their alkaloidal content. Mandelin (Jahresb., 1883) obtained a glucoside analogous to quercitrin, which he names violaquercitrin. It crystallizes out of hot water in fine yellow needles. When boiled with diluted acids, it is decomposed into quercetin, isodulcite and a fermentable glucose, C27H30O16 = C6H14O6 + C6H12O6 + C15H10O7. he also obtained salicylic acid from several species of viola. (A. JT. P., 1882, 10.) Kraemer (Inaug. Diss., Marking, 1896) detected methyl salicylate and this was later confirmed by Schimmel & Co. See also Gadd's article, Y. B. P., 1905, 466. The herbaceous parts of various species of violets are mucilaginous, emollient, and slightly laxative, and have been used in pectoral, nephritic, and cutaneous diseases. In Europe a syrup prepared from the fresh flowers of Viola odorata is employed as an addition to demulcent drinks, and as. a laxative for infants. The root, which has a bitter, nauseous, slightly acrid taste, acts in the dose of from thirty grains to a drachm (2.0-3.9 Gm.) as an emetic and cathartic. It is probable that the same property is possessed by the roots of all the violets, as it is known to be by several species of lanidium, which belongs to the same family. The existence in small proportion of the emetic principle in the leaves and flowers accounts for their expectorant properties.


(2) Common Names: (1) Blue violet, Bird's-foot violet; (2) Sweet violet, Sweet-scented violet.  
Nat.Ord. Violaceae.
Part Used: The whole plant of Viola pedata, L; Viola odorata, L. and other species of Viola.  

History and Description. The Blue violet is common to the United States, growing from Maine to Florida, and west to Missouri, in dry woods and pastures, and sandy places, flowering in May and June. Occasionally a second flowering occurs in August and September. The herb and root are used, and impart their virtues to water. The taste of the flowers is sweet and mucilaginous; of the rhizome, bitter, mucilaginous, and sub-acrid. The Viola odorata, or Sweet violet, of Europe, is much cultivated in this country on account of its beautiful, flowers, which appear in April and May. The flowers of this species are made into a syrup which is official in the French Codex. Of fresh violet petals (the deep-blue ones only, deprived of the calyx), take 10 parts, and boiling water, 20 parts. Infuse, and add to 21 parts of infusion 38 parts of sugar. Both of these plants possess similar properties; the flowers are commonly employed, but the whole plant is medicinal. The flowers should be gathered as soon as they are fully expanded, the sepals removed, and then carefully dried. According to P. L. Simmonds (Amer. Jour. Pharm., 1891, p. 201), the whole plant of Viola odorata is sold in a dry state in all the bazaars of Bengal, and is given in infusion as a diaphoretic in fevers. In large doses it nauseates and often produces vomiting. The Romans had a wine of violet flowers, and it is said they are still used in the preparation of sherbets.

Chemical Composition. The root, leaves and seeds of these odoriferous plants are emetic in larger doses. Boullay (1828) found the whole plant of V. odorata to contain an acrid and poisonous principle which he called violine. It resembles emetine in its action, is a pale-yellow or white powder of bitter and acrid taste, more soluble in water than emetine, insoluble in ether, quite soluble in alcohol, and forming an insoluble compound with tannin solution. It also exists in other plants of this family, particularly in the rhizomes of the perennial, and especially the stemless species of violet. It is not present, however, in the pansy (see below). The root also contains starch, yellow coloring matter, gum, traces of volatile oil, etc. The flowers contain a blue coloring matter, turning green with alkalies. As to the odoriferous principle of the violet, it has not yet been definitely established whether it is identical with the synthetical violet perfume from orris root. (Regarding the latter, see Henry Kraemer, Amer. Jour. Pharm., 1895, pp. 346-356.) K. Mandelin (Dissert., 1881; see Amer. Jour. Pharm., 1882, p. 11) found the leaves of V. odorata to contain a substance which, after boiling, yielded salicylic acid (also see Related Species, below). Boiling water extracts the virtues of these plants.    

Action, Medical Uses, and Dosage. The flowers and seeds of V. odorata act as laxatives in doses of 3 or 4 drachms, rubbed up with sugar and water; the root in 1/2 or 1-drachm doses is emeto-cathartic, but it is uncertain in its action. The odorous emanations from the flowers have caused faintness and giddiness, and in one case were supposed to have brought on apoplexy. The seeds have been recommended in uric acid gravel. Blue violet is mucilaginous, emollient, and slightly laxative; also antisyphilitic and useful, when combined with Corydalis formosa, in syphilis. Has been used in pectoral, nephritic and cutaneous affections, especially crusta lactea. The plant should be used when fresh, as drying destroys its active properties. Prof. Scudder says of it that "it stimulates waste and secretion, relieves nervous irritability, and improves nutrition".  The V. tricolor, or pansy, may be used as a substitute. The roots of these plants are bitterish and slightly acrid, and in doses of from 8 to 10 grains are tonic; from 25 to 30 grains, purgative; and from 40 to 60 grains, emetic.   

Related Species. Viola tricolor, L.  Heartsease, Johnny jump-up, Pansy. The wild-growing species of pansy is official in the German Pharmacopoeia, and its variety arvensis in the French Codex. Its corolla has the 3 colors-blue, yellow, and purple. According to Boullay (1828), no emetic violine is present, but a yellow coloring principle, and an abundance of mucilage was found. The yellow principle has since been shown by Mandelin (Pharm. Zeitschrift fr Russland, 1883, p. 329) to be a glucosid violaquercitrin
(C42H42O24). From hot solution it forms fine yellow acicular crystals, soluble in alkalies and reprecipitated by acids; when boiled with diluted acids it is split into quercetin, glucose, and a fluorescent body. Previously (1881), Mandelin obtained free salicylic acid from the dried herb, varying from 0.06 to 0.14 percent. It occurs in several other species of Viola. Griffith and Conrad (1884) found 0.13 per cent in the leaves, 0.08 per cent in the stems, and 0.05 per cent in the root; the flowers contained but a trace. The fresh leaf-buds, when rubbed between the fingers, exhibit a distinct odor of methyl salicylate (see monograph on Viola tricolor, by Henry Kraemer, Dissert., Marburg, 1897). The immoderate use of Viola tricolor is said to derange the gastro-intestinal functions, and to induce diuresis, sweating, and a pustular skin eruption. It imparts to the urine a feline odor. Its chief use is as a remedy for the moist eczematous eruptions which are prone to occur on the scalp and face of children. From 5 to 10 drops of a strong tincture may be added to 4 fluid ounces of water, the dose of the mixture being a teaspoonful every 4 hours. In Europe it is used as a blood purifier, and in catarrhal affections of the bronchiae and intestines.

Did you find what you were seeking? If not use the site search box at the top right hand of the page or else browse the site library.
 

      Library