A curcuminoid is a linear diarylheptanoid, a relatively small class of plant secondary metabolites that includes

curcumin Curcumin is a bright yellow chemical produced by plants of the ''Curcuma longa'' species. It is the principal curcuminoid of turmeric (''Curcuma longa''), a member of the ginger family, Zingiberaceae. It is sold as a herbal supplement, cosmet ...

, demethoxycurcumin, and bisdemethoxycurcumin, all isolated from turmeric ( curcuma longa). These

compound Compound may refer to: Architecture and built environments * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive struc ...

s are

natural phenol In biochemistry, naturally occurring phenols are natural products containing at least one phenol functional group. Phenolic compounds are produced by plants and microorganisms. Organisms sometimes synthesize phenolic compounds in response to ecol ...

s and produce a pronounced

yellow Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In th ...

color that is often used to color foods and medicines. Curcumin is obtained from the

root In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the su ...

turmeric Turmeric () is a flowering plant, ''Curcuma longa'' (), of the ginger family, Zingiberaceae, the rhizomes of which are used in cooking. The plant is a perennial, rhizomatous, herbaceous plant native to the Indian subcontinent and Southeast ...

. Curcuminoids are

soluble In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution. The extent of the solubi ...

dimethyl sulfoxide Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula ( CH3)2. This colorless liquid is the sulfoxide most widely used commercially. It is an important polar aprotic solvent that dissolves both polar and nonpolar compounds a ...

(DMSO),

acetone Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscibl ...

and

ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...

, but are poorly soluble in

lipid Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids in ...

s. It is possible to increase curcuminoid solubility in

aqueous An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, or sodium chloride (NaCl), in water would be re ...

phase with

surfactant Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsion#Emulsifiers , ...

s or co-surfactants. Most common derivatives have different

substituent A substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. (In organic chemistry and biochemistry, the terms ''substituent'' and ''functional group'', as well as '' side ...

s on the

phenyl group In organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula C6 H5, and is often represented by the symbol Ph. Phenyl group is closely related to benzene and can be viewed as a benzene ring, minus a hydrogen ...

s. There is an increasing demand for demethoxycurcumin, bisdemethoxycurcumin, and other curcuminoids because of their

biological activity In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or ...

Cyclodextrins

Curcuminoids form a more stable

complex Complex commonly refers to: * Complexity, the behaviour of a system whose components interact in multiple ways so possible interactions are difficult to describe ** Complex system, a system composed of many components which may interact with each ...

with solutions which contain

cyclodextrin Cyclodextrins are a family of cyclic oligosaccharides, consisting of a macrocyclic ring of glucose subunits joined by α-1,4 glycosidic bonds. Cyclodextrins are produced from starch by enzymatic conversion. They are used in food, pharmaceutical ...

towards hydrolytic degradations. The stability differs between size and characterization of the cyclodextrins that are used. Dissolution of demethoxycurcumin, bisdemethoxycurcumin and curcumin are greatest in the hydroxypropyl-γ-cyclodextrin (HPγCD) cavity. The curcuminoids which have a

connected to the phenyl groups show more affinity for the HPγCD compound. Degradation rate is depended on pH of the solution and how much protection the cyclodextrins provide the curcuminoids. The derivatives are usually more stable than curcumin against hydrolysis in cyclodextrin solution. No

covalent bond A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between ato ...

s are present between the cyclodextrins and the curcuminoids so they are easily released from the complex by simple solvent effects.

Composition and production

The curcumin derivatives demethoxycurcumin and bisdemethoxycurcumin may have

antioxidant Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubrica ...

activities useful in maintaining

shelf-life Shelf life is the length of time that a commodity may be stored without becoming unfit for use, consumption, or sale. In other words, it might refer to whether a commodity should no longer be on a pantry shelf (unfit for use), or no longer on a ...

of food products. Pure chemicals of curcumin and its derivatives are not available in the open market. Commercially available curcumin contains 77% curcumin, 17% demethoxycurcumin and 3% bisdemethoxycurcumin from the

herb In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicina ...

'' Curcuma longa''. Curcumin is mainly produced in

industry Industry may refer to: Economics * Industry (economics), a generally categorized branch of economic activity * Industry (manufacturing), a specific branch of economic activity, typically in factories with machinery * The wider industrial sector ...

as a

pigment A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compou ...

by using turmeric

oleoresin Oleoresins are semi-solid extracts composed of resin and essential or fatty oil, obtained by evaporation of the solvents used for their production. The oleoresin of conifers is known as crude turpentine or gum turpentine, which consists of oil of ...

as the starting material which curcuminoids can be isolated from. After the isolation of the curcuminoids, the

extract An extract is a substance made by extracting a part of a raw material, often by using a solvent such as ethanol, oil or water. Extracts may be sold as tinctures, absolutes or in powder form. The aromatic principles of many spices, nuts ...

which is about 75%

liquor Liquor (or a spirit) is an alcoholic drink produced by distillation of grains, fruits, vegetables, or sugar, that have already gone through alcoholic fermentation. Other terms for liquor include: spirit drink, distilled beverage or h ...

mainly contains

oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturated ...

resin In polymer chemistry and materials science, resin is a solid or highly viscous substance of plant or synthetic origin that is typically convertible into polymers. Resins are usually mixtures of organic compounds. This article focuses on nat ...

and more curcuminoids which can be isolated further.

Research

Laboratory and clinical studies have not confirmed any medical use for curcumin, which is difficult to study because it is both unstable and poorly

bioavailable In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation. By definition, when a medication is administered intravenously, its bioavailability is 100%. Ho ...

, and is unlikely to produce useful lead compounds for

drug development Drug development is the process of bringing a new pharmaceutical drug to the market once a lead compound has been identified through the process of drug discovery. It includes preclinical research on microorganisms and animals, filing for re ...

. Curcumin, which shows positive results in most

drug discovery In the fields of medicine, biotechnology and pharmacology, drug discovery is the process by which new candidate medications are discovered. Historically, drugs were discovered by identifying the active ingredient from traditional remedies or b ...

assays, is regarded as a false

lead Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cut, ...

that medicinal chemists include among "

pan-assay interference compounds Pan-assay interference compounds (PAINS) are chemical compounds that often give false positive results in high-throughput screens. PAINS tend to react nonspecifically with numerous biological targets rather than specifically affecting one desired ...

". This attracts undue experimental attention while failing to advance as viable therapeutic or drug leads.
See also:

References

{{Curcuminoid Experimental medical treatments