Morindone is an anthraquinone compound obtained from various ''

Morinda ''Morinda'' is a genus of flowering plants in the madder family, Rubiaceae. The generic name is derived from the Latin words ''morus'' "mulberry", from the appearance of the fruits, and ''indica'', meaning "of India". Description Distributed i ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

, especially '' M. tinctoria'', but also '' M. citrifolia''. Its principal use is as a dye, but it has also been investigated for anticancer and microbial uses.

Preparation

Morindone is obtained from the root bark of ''M. tinctoria'' or related species in two stages. In the first step, small roots of immature plants are boiled in alcohol to obtain

morindin Morindin is an anthraquinone glycoside present in several ''Morinda'' species, especially '' M. tinctoria'' (the Indian mulberry tree) and '' M. citrifolia'' (noni). Chemical or enzymatic hydrolysis of morindin yields its bright red aglycone, mor ...

, a yellowish substance which can also be used in dyeing. Further heating brings about

hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolys ...

of two

glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, u ...

monomer In chemistry, a monomer ( ; '' mono-'', "one" + ''-mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization. Classification ...

s through sublimation, leaving intensely red crystals. ''M. tinctoria'' is extensively grown in

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

for commercial production. Moridin content in the roots peaks in two to three years and drops off considerably after that; some attempts have been made to speed up production using tissue cultures.

Use as a dye

Morindone requires a

mordant A mordant or dye fixative is a substance used to set (i.e. bind) dyes on fabrics by forming a coordination complex with the dye, which then attaches to the fabric (or tissue). It may be used for dyeing fabrics or for intensifying stains in ...

, and the color obtained varies depending on the substance used. Aluminum mordants give a red color, while iron and chromium produce duskier shades. The traditional mordant used in Java, jirak bark ('' Symplocos fasciculata''), is rich in aluminum salts. Compared to modern dyestuffs, morindone is not as fast or as stable. Since it can be readily cultivated, however, interest in it remains high. Recent research has examined cell culture as a means of increasing yields.

References

* * Note that the chemical formula given here is incorrect; this reference was used only for physical properties and preparation of substance. * *{{cite web, url=http://www.worldagroforestrycentre.org/sea/products/AFDbases/AF/asp/SpeciesInfo.asp?SpID=18062, title=Morinda citrifolia, publisher=World Agroforestry Centre, accessdate=2009-01-05, archive-url=https://web.archive.org/web/20110930043050/http://www.worldagroforestrycentre.org/sea/products/AFDbases/AF/asp/SpeciesInfo.asp?SpID=18062, archive-date=2011-09-30, url-status=dead Natural dyes Anthraquinone dyes Catechols Trihydroxyanthraquinones