Hydroxytyrosol and Derivatives: Isolation, Synthesis, and Biological Properties

Abstract

Hydroxytyrosol is a phenol found predominantly in the olive tree (Olea europea). It shows a broad spectrum of beneficial effects such as cancer chemoprevention by inducing apoptosis, cardioprotection and anti-atherogenic activity, skin photoprotection and anti-inflammatory activity. These biological properties are based on scavenging of reactive oxygen species by hydroxytyrosol, being more active than antioxidant vitamins and synthetic antioxidants. Its biological activities and beneficial effects on human health has stimulated the development of new methods of extraction and purification from olive mill wastewater, from table olive processing, or from leaves. Different procedures for the chemical and enzymatic synthesis of hydroxytyrosol have been developed from tyrosol, from 3,4-dihydroxyphenylacetic acid and its methyl ester, and from oleuropein.Some hydroxytyrosol acyl derivatives have been prepared by chemical and chemoenzimatic methods in order to increase both stability and solubility in lipophilic preparations. Mechanistic experiments on hydroxytyrosol oxidation and isolation of species formed by oxidation are also reported.

A Straightforward Access to New Families of Lipophilic Polyphenols by Using Lipolytic Bacteria

“…In this work, special attention has been focused on hydroxytyrosol (HT) and 3,4-dihydroxyphenylglycol (DHPG), which predominate in leaves and fruits of olive trees ( Olea europea ), either free or as acyl derivatives, and display antioxidant activity [15]. We have developed a novel enzymatic method to obtain targeted mono- or di-acylated derivatives of the polyphenols.…”

Complexation of hydroxytyrosol with β-cyclodextrins. An efficient photoprotection

“…2 It exerts a broad spectrum of biological activities based on its antioxidant properties such as cancer chemoprevention, cardioprotection, anti-inflammatory properties or skin photoprotection. 1,3,4 Hydroxytyrosol (HT) acts as a more potent radical scavenger than other natural or less popular synthetic antioxidants, probably due to the low value of the OeH bond dissociation enthalpy. 3 Nevertheless, polyphenolic compounds are known to undergo thermal and light-induced decomposition, 5 a property that might limit their practical use in food and in pharmaceutical or cosmetic products, especially under certain storage conditions.…”

Effect of olive‐derived antioxidants (3,4‐dihydroxyphenylethanol and 3,4 dihydroxyphenylglycol) on sperm motility and fertility in liquid ram sperm stored at 15°C or 5°C

“…A large amount of phenolic component could be extracted of olive fruit, as occur with hydroxytyrosol (3,4 dihydroxyphenylethanol, HT) and 3,4-dihydroxyphenylglycol (DHPG). HT is a simple phenol obtained from the alperujo (the waste of olive oil) which has a high antioxidant ability (Fernández-Bolaños, López, Fernández-Bolaños, & Rodríguez, 2008), reduces the oxidation of low-density lipoproteins, protects against H 2 O 2 cytotoxicity and minimizes lactate dehydrogenase activity (Choucair, Saliba, Jaoude, & Hazzouri, 2018;Hashimoto et al, 2004;Roche et al, 2009). In relation to DHPG, it is also an alperujo-derived phenolic component with high antioxidant and anti-inflammatory potential, similar to HT but with an additional hydroxyl group in the β-position (Bermúdez-Oria, Rodríguez-Gutiérrez, Rodríguez-Juan, González Benjumea, & Fernández-Bolaños, 2018).…”