Synthesis and antioxidant evaluation of lipophilic oleuropein aglycone derivatives

Abstract

Oleuropein is the most important phenolic compound present in olive cultivars, but it is scarcely present in extra virgin olive oil (EVOO) due to its high hydrophilicity and degradability. Thus, a set of oleuropein aglycone derivatives were synthesized by transacetylation under mild conditions with the aim of circumventing these drawbacks and making the active moiety in oleuropein suitable to be added to food fats. The oleuropein aglycone (closed ring form) is obtained by hydrolyzing oleuropein using Lewis acid catalysis. Then, the permeation profiles as well as the antioxidant capacity of the oleuropein aglycone derivatives were evaluated by ORAC, DPPH assays and by ROS formation using the SH-SY5Y cell line. The biological activities of the obtained compounds exhibited a dependence on their level of lipophilicity.

Erbium Salts as Non-Toxic Catalysts Compatible with Alternative Reaction Media

“…Exploiting the ability of erbium(III) to coordinate the oxygen atom, a new group of lipophilic oleuropein aglycone derivatives was synthesized through a transacetylation reaction with oleuropein and different fatty alcohols (Figure 2e) [64]. Oleuropein aglycone derivatives with long saturated and unsaturated alkyl chains were evaluated in terms of their lipophilicities and In recent decades, exhaustive physicochemical data have been provided for the presence-in virgin olive oil and other oils-of two active principles characterized by a dialdehyde moiety conjugated with 2-(3,4-hydroxyphenyl) ethyl (3S,4E)-4-formyl-3-(2-oxoethyl)hex-4-enoate (3,4-DHPEA-EDA) and 2-(3,4-hydroxyphenyl) ethyl (3S,4E)-4-formyl-3-(2-oxoethyl)hex-4-enoate (p-HPEA-EDA) [57,58] that show peculiar sensory and health properties [59,60].…”

“…Exploiting the ability of erbium(III) to coordinate the oxygen atom, a new group of lipophilic oleuropein aglycone derivatives was synthesized through a transacetylation reaction with oleuropein and different fatty alcohols (Figure 2e) [64]. Oleuropein aglycone derivatives with long saturated and unsaturated alkyl chains were evaluated in terms of their lipophilicities and antioxidant capacities, both in chemical and biological environments, to establish whether they could be potentially used as antioxidants in a fatty matrix and if augmented lipophilicities would correspond to better cellular internalization and antioxidant activity.…”

Montmorillonite K10-Catalyzed Solvent-Free Conversion of Furfural into Cyclopentenones

“…Lowering the environmental impact of industrial activities is particularly important for the pharmaceutical industry, as it is very often indicated as the principal source of environmental pollution [45]. In recent years, the use of renewable sources or waste materials as starting products has become very important for obtaining useful pharmaceutical synthons [46][47][48]. In this context, furfural is an important biomass compound that is derived and used to synthesize different bio-products [49].…”

3,4-DHPEA-EA Peracetylated (3,4-DHPEA-EA(P)) Attenuates H₂O₂-Mediated Cytotoxicity in C2C12 Myocytes <em>via</em> Inactivation of p-JNK/p-c-Jun Signaling Pathway

“…In last years, the importance of the antioxidant activity of 3,4-DHPEA-EA [9][10][11] and its derivatives at the level of skeletal muscle has emerged [12][13][14]. Skeletal muscle is a tissue in which ROS play particular importance: at low concentrations ROS act as signaling molecules in signal transduction pathways; instead at high concentrations they can result in oxidative stress and muscular atrophy [15].…”