 | |
| Names | |
|---|---|
| IUPAC name Methyl (2S,3E,4S)-4-{2-[2-(3,4-Dihydroxyphenyl)ethoxy]-2-oxoethyl}-3-ethylidene-2-(β-D-glucopyranosyloxy)-2H-pyran-5-carboxylate | |
| Systematic IUPAC name Methyl (2S,3E,4S)-4-{2-[2-(3,4-Dihydroxyphenyl)ethoxy]-2-oxoethyl}-3-ethylidene-2-{[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy}-2H-pyran-5-carboxylate | |
| Other names 2-(3,4-Dihydroxyphenyl)ethyl [(2S,3E,4S)-3-ethylidene-2-(β-D-glucopyranosyloxy)-5-(methoxycarbonyl)-3,4-dihydro-2H-pyran-4-yl]acetate | |
| Identifiers | |
3D model (JSmol) | |
| ChEMBL | |
| ChemSpider |
|
| ECHA InfoCard | 100.046.466 |
| UNII | |
| |
| |
| Properties | |
| C25H32O13 | |
| Molar mass | 540.518 g·mol−1 |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Oleuropein is aglycosylated seco-iridoid, a bitterphenolic compound found in greenolive skin, flesh, seeds, and leaves.[1] The term oleuropein is derived from the botanical name of the olive tree,Olea europaea.
Because of itsbitter taste andastringency, oleuropein must be partially removed or decomposed to make olives edible. During processing of bitter and inedible green olives for consumption as table olives, oleuropein is removed from olives via a number of methods, including by immersion inlye.[2][3]
Oleuropein is a derivative ofelenolic acid linked to the orthodiphenolhydroxytyrosol by anester bond and to a molecule ofglucose by aglycosidic bond.[4] When olives are immersed in a lye solution, the alkaline conditions lead to hydrolysis of the ester bond. The basic conditions also significantly increases thesolubility of these derivatives, facilitating their release into thelye solution.[5][6]
The high pH accelerates the oxidation of the phenolics, leading to blackness, as during their normal ripening, if the solution is oxygenated by air injection (alkaline oxidation of olives is also called theCalifornia process).[7][8]
The lye solution is replaced several times until the bitter taste has dissipated. An alternative process usesamberlite macroporousresins to trap the oleuropein directly from the solution, reducing waste water while capturing the extracted molecules.[9][10]
Enzymatic hydrolysis during the maturation of olives is also an important process for the decomposition of oleuropein and elimination of its bitter taste.[6][11]
Green olives may be treated industrially withferrous gluconate (0.4 wt. %)[7] to change their color to black.[12]Gluconate, an edible oxidation product of glucose, is used as non-toxic reactant to maintain Fe2+ in solution. When in contact with polyphenols, theferrous ions form a black complex, giving the final color of the treated olives.[9][10][7] Black olives treated withiron(II) gluconate are also depleted inhydroxytyrosol, as iron salts arecatalysts for its oxidation.[13]
Oleuropein has been proposed as aproteasome activator.[14][15]
| International | |
|---|---|
| National | |
| Other | |
