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VIOLA
- VIOLET (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.
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 Did you find what you
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