Madder root

Mordant dyes have hydroxy groups in their molecular stmcture that are capable of forming complexes with metals. Although a variety of metals such as iron, copper, aluminum, and cobalt have been used, chromium is most preferable as a mordant. Alizarin or Cl Mordant Red 11 [72 8-0] (1) (Cl 58000), the principal component of the natural dye obtained from madder root, is the most typical mordant dye (see Dyes, natural). The aluminum mordant of alizarin is a well-known dye by the name of Turkey Red and was used to dye cotton and wool with excellent fastness. However, as is the case with many other mordant dyes, it gave way to the vat or the azoic dyes, which are applied by much simpler dyeing procedures. 

Krapp-farbe, /. madder color, madder dye. -filrbcn, n. madder dyeing, -farbstoff, -farbc-atoff, m. alizarin, -gelb, n. madder yellow, xanthin. -lack, m. madder lake. -rot n. madder red, alizarin, -stoff, m. alizarin, -wurzel, /. madder root. 

Using his new understanding of structural chemistry, Perkin studied one of the most important natural dyes known madder red. Madder roots,... 

For the extraction of colourants from Rubia tinctorum (Figure 13.2) roots, mostly methanol, [42] water-methanol (with the addition of n-amyl alcohol in the case of lake extraction)[19,20] or water-ethanol solutions[38] are used. Additional hydrolysis can be performed with hydrochloric acid[8,19,20,34] and trifluoroacetic acid,[42] but also with madder root enzymes,[42] responsible for cleavage of anthraquinone glycosides into the corresponding aglycones and sugars. 

G.C.H. Derksen, M. Naayer, T.A. van Beek, A. Capelle, I.K. Haaksman, H.A. van Doren and JE. Groot, Chemical and enzymatic hydrolysis of anthraquinone glycosides from madder roots, Phytochem. Anal., 14, 137 144 (2003). 

I. Boldizsar, Z. Sziics. Z. Fiizfai and I. Molnar Perl, Identification and quantification of the constituents of madder root by gas chromatography and high performance liquid chromatogra phy, J. Chromatogr. A, 1133, 259 274 (2006). 

G.C.H. Derksen, T.A. van Beek, JE. Groot and A. Capelle, High performance liquid chromato graphic method for the analysis of anthraquinone glycosides and aglycones in madder root (Rubia tinctorum L.), J. Chromatogr. A, 816, 277 281 (1998). 

Alizarin or l 2-dihydroxyanthraquinone is one of the most important dyes. Like indigo, the dye occurs in the plant (the madder root) as the glucoside of the leuco-compound. The cultivation of the madder plant, which, chiefly in southern France, extended over large areas, was brought to an end by the synthesis of the dye from the anthracene of coal-tar (Graebe and Liebennann, 1869). By distillation with zinc dust according to the method of Baeyer, these two chemists had previously obtained anthracene from alizarin. 

Rubia chinensis Regel Maack R. cordifolia Thunb. R. cordifolia L. f. pratensis (Maxim.) Kitag. R. mungista Roxb. R. sylvatica (Maxim.) Nakai Qian Cao (Madder) (root) Rubierythrinic acid, alizarin, purpurin, pseudopurpurin, munjistin.3349 Hemostatic, shorten the blood clotting time, antibacterial, antitussive, stimulate uterine contractions. 

In recent decades, numerous dyer s plants of the type of madder (Rubia tinctorum L.) have again been investigated for their constituents. With the aid of modern methods of instrumental analysis, no less than 23 different components belonging to the class of hydroxyanthraquinones have been identified in madder roots (32-3A), for instance, besides five hydroxyanthraquinone glycosides, of which rubia-nin (Constitution VIII in table I) (35) is of particular interest,... 

The dried root was also found to contain purpuroxanthin (II) formed by separation of CO2. from munjistin (VII). Pseudopurpurin (XXIII) is probably decarboxylated with formation of purpurin (XXI) when the madder root is dried. The dried madder root also contains the following hydroxyanthraquinone dyes in small amounts nordamna-canthal (VI), quinizarin (IX), 1,4-dihydroxy-2-hydroxymethylanthra-quinone (XI), quinizarin-2-carboxylic acid (XII), anthragallol (XVIII), and anthragallol-3-methyl ether (XX) (32, 34, 39). 

In the past, the red root was traded as "East Indian madder root". 

In order to strip the dyes of madder dyeings completely from the fiber, they must be extracted in acid solution at temperatures up to roughly 100° C. Comparative solutions produced by extraction from dyer s plants such as madder root must also be prepared in the same manner at acid pH for the TLC. The anthraquinone dyes are present in the dyer s plants partly in the form of glycosides. These glycosides must be split hydrolytically with acids in order to obtain for the TLC a comparative solution that contains only free hydroxyanthraqui-nones and no hydroxyanthraquinone glycosides. 

In the extraction of powdered madder roots with 10% sulfuric acid, followed by shaking with ethyl acetate, we see that the ethyl acetate contains only a very small amount of pseudopurpurin or not at all. However, when we investigate madder dyeings on old carpets by the same method, the thin-layer chromatogram often shows that pseudopurpurin is present in roughly the same amount as purpurin. What is the explanation for this ... 

In the madder root, however, the pseudopurpurin is present in the form of the relatively hydrolysis-stable glycoside galiosin. In this case., it is necessary to heat for 20-30 minutes with dilute acids before all dyes can be shaken out with ethyl acetate. In this process, the pseudopurpurin is completely decarboxylated. 

With this method, we have found that the sample of "Rose madder" contains only traces of purpurin besides of pseudopurpurin. The method is also useful for investigating madder types that contain only small amounts of purpurin (formed probably from pseudopurpurin) as well as pseudopurpurin, but no alizarin. Examples of these madder types are the South American relbun roots such as Relbunium hypocarpium (L.) HEMSL. and R. ciliatum (L.) HEMSL. and the Japanese madder roots of Rubia akane. 

Rubia tinctorum alizarin and purpurin can be clearly identified by the marked spots. Pseudopurpurin has been converted into purpurin by decarboxylation, because the old extraction method (boiling with 10% sulfuric acid, followed by shaking with ethyl acetate) has been used to isolate the dyes from the madder roots. 

Pseudopurpurin, made from a synthetic pseudopurpurin lake by extraction with the new method. In contrast to the sample of "Rose Madder Genuine" (made from madder roots) besides of the principal dye only traces of purpurin have been found, but not alizarin. Therefore is is possible to distinguish natural and synthetic pseudopurpurin lakes by this method. 

Most textiles found in historic museums are natural fibers dyed with natural dyestuffs. Therefore, in this experiment two common textiles, cotton and wool, were dyed with safflower, madder root, logwood chips, and indigo. These dyes were chosen to represent a range of colors often found in historic textiles. The cotton and wool textiles were obtained... 

The blue dye indigo, derived from the plant Indigofera tinctoria, has been used in India for thousands of years. Traders introduced it to the Mediterranean area and then to Europe. Tyrian purple, a natural dark purple dye obtained from the mucous gland of a Mediterranean snail of the genus Murex, was a symbol of royalty before the collapse of the Roman empire. Alizarin, a bright red dye obtained from madder root Rubia tinctorum), a plant native to India and northeastern Asia, has been found in cloth entombed with Egyptian mummies. 

Naturally occurring dyestuff, for example, indigo shrub, madder root, cochineal insects, Persian berries, and the like, have been known and used for centuries. These soluble dyes were rendered insoluble in water by treatment with suitable precipitating agents and used as lakes. With the increase in the variety of synthetic dyes available and multiplicity... 

Turkey Red.—Alizarin is the chief constituent of the coloring matter Turkey red, which has been known since ancient times and which was obtained from the root of the madder plant, Rubia tinctorum L. The substance is of special interest because the determination of its constitution was one of the early triumphs of organic chemistry and because it was the first natural dye to be synthetically prepared. The name is derived from the oriental name for the madder, viz., alizari. In the madder root it is present as a glucoside known as ruberythric acid, which, on hydrolysis by fermentation or by boiling with acids, yields glucose and alizarin. Alizarin is a solid which sublimes as orange red needles, m.p. 289°, insoluble in water but slightly soluble in alcohol. 

Nitro, amino and sulphonic acid derivatives of alizarin are also dyes of various colors and are known as alizarin orange, alizarin maroon, alizarin red, etc. Also there is present in the madder root another dye compound known as puipurin which is 1-2-4-tri-hydroxy anthraqui-none. Isomeric tri-hydroxy anthraquinones are dyes also but it is interesting that in all of these poly-hydroxy anthraquinones which are dyes two of the hydroxyls are always in the 1-2 positions. 

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