Probing Downstream Olive Biophenol Secoiridoids.

Numerous bioactive biophenol secoiridoids (BPsecos) are found in the fruit, leaves, and oil of olives. These BPsecos play important roles in both the taste of food and human health. The main BPseco bioactive from green olive fruits, leaves, and table olives is oleuropein, while olive oil is rich in oleuropein downstream pathway molecules. The aim of this study was to probe olive BPseco downstream molecular pathways that are alike in biological and olive processing systems at different pHs and reaction times. The downstream molecular pathway were analyzed by high performance liquid chromatography coupled with electrospray ionization mass spectrometry (HPLC-ESI/MS) and typed neglected of different overlap (TNDO) computational methods. Our study showed oleuropein highest occupied molecular orbital (HOMO) and HOMO-1 triggered the free radical processes, while HOMO-2 and lowest unoccupied molecular orbital (LUMO) were polar reactions of glucoside and ester groups. Olive BPsecos were found to be stable under acid and base catalylic experiments. Oleuropein aglycone opened to diales and rearranged to hydroxytyrosil-elenolate under strong reaction conditions. The results suggest that competition among olive BPseco HOMOs could induce glucoside hydrolysis during olive milling due to native olive ß-glucosidases. The underlined olive BPsecos downstream molecular mechanism herein could provide new insights into the olive milling process to improve BPseco bioactives in olive oil and table olives, which would enhance both the functional food and the nutraceuticals that are produced from olives.

Oleuropein: Molecular Dynamics and Computation.

BACKGROUND: Olive oil and table olive biophenols have been shown to significantly enrich the hedonic-sensory and nutritional quality of the Mediterranean diet. Oleuropein is one of the predominant biophenols in green olives and leaves, which not only has noteworthy freeradical quenching activity but also putatively reduces the incidence of various cancers. Clinical trials suggest that the consumption of extra virgin olive oil reduces the risk of several degenerative diseases. The oleuropein-based bioactives in olive oil could reduce tumor necrosis factor α, interleukin-1ß and nitric oxide. Therefore, the quality of olive biophenols should be preserved and even improved due to their disease-fighting properties. OBJECTIVE: Understanding the molecular dynamics of oleuropein is crucial to increase olive oil and table olive quality. The objective of this review is to provide the molecular dynamics and computational mapping of oleuropein. METHOD: The oleuropein molecular bond sequential breaking mechanisms were analyzed through unimolecular reactions under electron spray ionization, collision activated dissociations, and fast atom bombardment mass spectrometry. RESULTS: Oleuropein is a biophenol-secoiridoid expressing different functionalities such as two π-bonds, two esters, two acetals, one catechol, and four hexose hydroxyls within 540 mw. The oleuropein solvent-free reactivity is leading to glucose loss and bioactive aglycone-dialdehydes via secoiridoid ring opening. CONCLUSION: Oleuropein electron distribution revealed that the free-radical non-polar processes occur from its highest occupied molecular orbital, while the lowest unoccupied molecular orbital is clearly devoted to nucleophilic and base site reactivity. This molecular dynamics and computational mapping of oleuropein could contribute to the engineering of olive-based biomedicine and/or functional food.

Soft-MS and Computational Mapping of Oleuropein.

Olive oil and table olives are rich sources of biophenols, which provides a unique taste, aroma and potential health benefits. Specifically, green olive drupes are enriched with oleuropein, a bioactive biophenol secoiridoid. Olive oil contains hydrolytic derivatives such as hydroxytyrosol, oleacein and elenolate from oleuropein as well as tyrosol and oleocanthal from ligstroside. Biophenol secoiridoids are categorized by the presence of elenoic acid or its derivatives in their molecular structure. Medical studies suggest that olive biophenol secoiridoids could prevent cancer, obesity, osteoporosis, and neurodegeneration. Therefore, understanding the biomolecular dynamics of oleuropein can potentially improve olive-based functional foods and nutraceuticals. This review provides a critical assessment of oleuropein biomolecular mechanism and computational mapping that could contribute to nutrigenomics.

E, Z and positional-monoenoic phyto-fatty acids influencing membrane fluidity: DSC and NMR experiments.

The membrane fluidity of biological tissues is highly influenced by the π-bond position and isomeric configuration in the long chain of phyto-fatty acids (FAs). Z, E and positional isomeric monoenoic lipids, i.e. the phytomolecules oleic (OA), elaidic (EA), vaccenic acid (TV) and its Z-isomer (CV), have been evaluated for their effects on the fluidity of cellular membranes. To this purpose the Differential Scanning Calorimetry (DSC) and Deuterium Nuclear Magnetic Resonance ((2)H-NMR), are suitable techniques to understand the supramolecular lamellar structure during the order (gel)-disorder (fluid) transition. It was found that the presence of CV concentration, induces the biomimetic system to reach the first step to fluid phase earlier than the membrane containing OA. DSC showed that the endothermic peak onset of the membrane containing CV occurs at a lower temperature than that of a membrane containing an equal amount of OA. (2)H-NMR investigation confirmed the last statement. In fact the study of the main phase transition of the two different systems, revealed that model membrane containing a 3% (w/w) of CV goes in ripple phase, i.e. the first step to the fluid state, at a lower temperature as compared to the membrane of an identical system with OA.

Ulivo alchemy: the bio- and tecno-molecular approach to MAC-Mediterranean aliment culture.

Sccoiridoid biophenols, contained in olive drupes, are enzymatically activated to provide a complex mechanism for the biological defence against pathogen attack. Their identification, quantitation and metabolic behaviour are investigated, by HPLC and NMR experiments, for the improvement of olivegrowing and of the production of oil and table olives.