Rubia tinctorum, the common madder or dyer's madder, is a plant species in the genus Rubia

Rubiá

aRubiá is a municipality in the Spanish province of Ourense. It has a population of 1734 and an area of 101 km²....

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The plant's roots contain several polyphenolic compounds like 1,3-Dihydroxyanthraquinone

1,3-Dihydroxyanthraquinone

1,3-Dihydroxyanthraquinone, also called purpuroxanthin or xanthopurpurin is an organic compound with formula that occurs in the plant Rubia cordifolia . It is one of ten dihydroxyanthraquinone isomers...

 (purpuroxanthin), 1,4-Dihydroxyanthraquinone

1,4-Dihydroxyanthraquinone

1,4-Dihydroxyanthraquinone, also called quinizarin or Solvent Orange 86, is an organic compound derived from anthroquinone. Quinizarin is an orange or red-brown crystalline powder. It is formally derived from anthraquinone by replacement of two hydrogen atoms by hydroxyl groups...

 (quinizarin), 1,2,4-Trihydroxyanthraquinone (purpurin) and 1,2-dihydroxyanthraquinone (alizarin

Alizarin

Alizarin or 1,2-dihydroxyanthraquinone is an organic compound with formula that has been used throughout history as a prominent dye, originally derived from the roots of plants of the madder genus.Alizarin was used as a red dye for the English parliamentary "new model" army...

). This latter gives its red colour to a textile dye known as Rose madder. It was also used as a colourant, especially for paint, that is referred to as Madder lake. The substance was also derived from another species, Rubia cordifolia

Rubia cordifolia

Rubia cordifolia, often known as Common Madder or Indian Madder, is a species of flowering plant in the coffee family, Rubiaceae...

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