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Madder (Rubia tinctorum
LINN.) Click on graphic for larger
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Madder
Botanical: Rubia tinctorum (LINN.) Family: N.O. Rubiaceae
---Synonyms---Krapp. Dyer's Madder. Robbia.
(French) Garance. ---Part Used---Root.
---Habitat---Southern Europe, including southern Britain, and
Mediterranean countries.
---Description---The stalks of the Madder are so
weak that they often lie along the ground, preventing the plant from
rising to its maximum height of 8 feet. The stalks are prickly, and the
whorls of leaves at the joints have spines along the midrib on the
underside, a feature that the French turn to advantage by using them for
polishing metal-work.
The herb is used as fodder for animals.
The flower-shoots spring from the joints in pairs, the loose spikes of
yellow, starry flowers blooming only in the second or third year, in June.
The thick, fleshy fibres that compose the perennial are about 1/4 inch
thick, and from their joining, or head, side roots run under the surface
of the ground for some distance, sending up shoots. The main and
side-roots are dried separately, their products being regarded as
different, that of a young, parent root being the best. They are covered
with a blackish rind, beneath which they are reddish, with a pale yellow
pith. In France, after drying, the outer layer is threshed off and
powdered and packed separately as an inferior product called mall. The
stripped roots are again heated - excepting in hot climates - then
powdered, and milled three times. The final product is packed in casks,
which in Holland are stamped by sworn assayers.
The best European Madder is Dutch, but that from Smyrna is said to be
even finer. The Turkey-red and other shades are adjective dyes, different
mordants bringing many shades of red, pink, lilac, purple, brown, orange
and black.
As a dye it colours milk, urine and bones, so that experiments in the
growth of bones can be conducted with its help.
Rubia tinctoria differs very slightly from the Wild Madder or
R. peregrina, and may be merely a variety.
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---Constituents---The root contains rubian,
rubiadin, ruberythric acid, purpurin, tannin, sugar and especially
alizarin. Pseudopurpurin yields the orange dye and
xanthopurpurin the yellow. The astringent taste, slight odour and
red colour, are imparted to water or alcohol.
The most interesting of the colouring substances is the alizarin, and
this is now termed dihydroscyanthraquinone. This occurs as orange-red
crystals, almost insoluble in water, but readily soluble in alcohol,
ether, the fixed oils and alkaline solutions. The alcoholic and aqueous
solutions are rose-coloured, the ethereal, golden-yellow; the alkaline,
violet and blue when concentrated, but violet red when sufficiently
diluted. A beautiful rose-coloured lake is produced by precipitating a
mixture of the solutions of alizarin and alum.
Alizarin was recognized by Graebe and Liebermann, in 1868, as a
derivative of anthracene - a hydrocarbon contained in coal-tar, and in the
same year they elaborated a method for preparing it commercially from
anthracene. Upon this arose rapidly a great chemical industry, and the
cultivation of Madder has, of course, decreased correspondingly until it
may be said that the coaltar products have entirely displaced the natural
ones.
---Medicinal Action and Uses---Although not as a
general rule employed medicinally, Madder has been reputed as effectual in
amenorrhoea, dropsy and jaundice.
When taken into the stomach it imparts a red colour to the milk and
urine, and to the bones of animals without sensibly affecting any other
tissue. The effect is observed most quickly in the bones of young animals
and in those nearest to the heart. Under the impression that it might
effect some change in the nervous system, it has been prescribed in
rachitis (rickets), but without noticeable favourable results. Dosage, 1/2
drachm three or four times daily.
---Other Species--- R. sylvestris, a
nearly allied species, hasbeen used as a remedy in liver diseases,
jaundice, gall and spleen complaints. The root, leaves and seeds are all
reputed as medicinally active.
R. cordifolia, or Bengal Madder, of India, yields the inferior
dye called Munjeet.
In France it is thought that the root of Galium cruciatum, or
Crosswort, might replace that of Madder.
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