Quercitron is a yellow natural dye

Natural dye

Natural dyes are dyes or colorants derived from plants, invertebrates, or minerals. The majority of natural dyes are vegetable dyes from plant sources – roots, berries, bark, leaves, and wood — and other organic sources such as fungi and lichens....

 obtained from the bark of the Eastern Black Oak (Quercus velutina), a forest tree

Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

 indigenous in North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

.
The name is a shortened form of quercicitron, from Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 quercus, oak, and citron, lemon, and was invented by Dr Edward Bancroft

Edward Bancroft

Edward Bancroft was an American physician and double-agent spy during the American Revolution.He worked as a spy for Benjamin Franklin in Britain before the Revolution, and also while serving as secretary to the American Commission in Paris...

 (1744–1821), who by act of parliament in 1785 was granted special privileges in regard to the importation and use of the substance. The dyestuff is prepared by grinding the bark in mills after it has been freed from its black epidermal layer, and sifting the product to separate the fibrous matter, the fine yellow powder which remains forming the quercitron of commerce.
The ruddy-orange decoction

Decoction

Decoction is a method of extraction, by boiling, of dissolved chemicals, or herbal or plant material, which may include stems, roots, bark and rhizomes. Decoction involves first mashing, and then boiling in water to extract oils, volatile organic compounds, and other chemical substances...

 of quercitron contains quercitannic acid, whence its use in tanning

Tanning

Tanning is the making of leather from the skins of animals which does not easily decompose. Traditionally, tanning used tannin, an acidic chemical compound from which the tanning process draws its name . Coloring may occur during tanning...

, and an active dyeing principle, quercitrin

Quercitrin

Quercitrin is a glycoside formed from the flavonoid quercetin and the deoxy sugar rhamnose. It is a constituent of the dye quercitron. It can be found in Tartary buckwheat ....

, C₂₁H₂₀O₁₂. The latter substance is a glycoside

Glycoside

In chemistry, a glycoside is a molecule in which a sugar is bound to a non-carbohydrate moiety, usually a small organic molecule. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. These can be activated by enzyme...

, and in aqueous solution under the influence of mineral acids it yields quercetin

Quercetin

Quercetin , a flavonol, is a plant-derived flavonoid found in fruits, vegetables, leaves and grains. It also may be used as an ingredient in supplements, beverages or foods.-Occurrence:...

, C₁₅H₁₀O₇, which is precipitated, and the methyl-pentose

Pentose

A pentose is a monosaccharide with five carbon atoms. Pentoses are organized into two groups. Aldopentoses have an aldehyde functional group at position 1...

 rhamnose

Rhamnose

Rhamnose is a naturally occurring deoxy sugar. It can be classified as either a methyl-pentose or a 6-deoxy-hexose. Rhamnose occurs in nature in its L-form as L-rhamnose . This is unusual, since most of the naturally occurring sugars are in D-form...

.

Quercetin is a crystalline powder of a brilliant citron yellow color, entirely insoluble in cold water and dissolving only sparingly in hot water, but quite soluble in alcohol.
Either by itself or in some form of its glucoside quercitrin, quercetin is found in several vegetable substances, among others in cutch, in Persian berries (Rhamnus cathartica

Rhamnus cathartica

Rhamnus cathartica , is a species in the family Rhamnaceae, native to Europe, northwest Africa, and western Asia, from the central British Isles south to Morocco, and east to Kyrgyzstan...

), buckwheat

Buckwheat

Buckwheat refers to a variety of plants in the dicot family Polygonaceae: the Eurasian genus Fagopyrum, the North American genus Eriogonum, and the Northern Hemisphere genus Fallopia. Either of the latter two may be referred to as "wild buckwheat"...

 leaves (Fagopyrum esculentum), Zante fustic wood (Rhus cotinus), and in rose petals.

Chemically, quercetin is a member of a fairly extensive class of natural coloring matters derived from phenyl benzoyl-pyrone or flavone, the constitution of which followed on the researches of St von Kostanecki, A. G. Perkin, Herzig, Goldschmidt and others. Among the related, coloring matters are: chrysin

Chrysin

Chrysin is a naturally occurring flavone chemically extracted from the blue passion flower . Honeycomb also contains small amounts. It is also reported in Oroxylum indicum or Indian trumpetflower.-Aromatase inhibition:...

 from poplar buds, apigenin

Apigenin

Apigenin is a flavone that is the aglycone of several glycosides. It is a yellow crystalline solid that has been used to dye wool. Apigenin may contribute to the chemopreventive action of vegetables and fruits...

 from parsley

Parsley

Parsley is a species of Petroselinum in the family Apiaceae, native to the central Mediterranean region , naturalized elsewhere in Europe, and widely cultivated as an herb, a spice and a vegetable.- Description :Garden parsley is a bright green hairless biennial herbaceous plant in temperate...

, luteolin

Luteolin

Luteolin is a yellow crystalline compound. It is a flavonoid; to be specific, it is one of the more common flavones. From preliminary research, it is thought to play a role in the human body possibly as an antioxidant, a free radical scavenger, a promoter of carbohydrate metabolism, or an immune...

 from mignonette

Mignonette

Mignonette is a genus of fragrant herbaceous plants native to the Mediterranean region and southwest Asia, from the Canary Islands and Iberia east to northwest India. The species include annuals, biennials and perennials, and grow to 40-130 cm tall...

 and dyer's broom, fisetin

Fisetin

Fisetin is a flavonol, a structurally distinct chemical substance that belongs to the flavonoid group of polyphenols. It can be found in many plants, where it serves as a colouring agent...

 from young fustic and yellow cypress, galangin

Galangin

Galangin is a flavonol found in high concentrations in Alpinia officinarum . It is also found in the galangal rhizome and in propolis. Galangin has been shown to slow the increase and growth of breast tumor cells in vitro.-External links:*...

 from galangal

Galangal

Galangal is a rhizome of plants of the genus Alpinia or Kaempferia in the ginger family Zingiberaceae, with culinary and medicinal uses originated from Indonesia...

 root, and myricetin

Myricetin

Myricetin is a naturally occurring flavonol, a flavonoid found in many grapes, berries, fruits, vegetables, herbs, as well as other plants. Walnuts are a rich dietary source. Trace amounts can be found as glycosides. It is one of the phenolic compounds present in red wine.Myricetin has antioxidant...

from Nageia nagi.