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M J Tovar - One of the best experts on this subject based on the ideXlab platform.

  • changes in the phenolic composition of virgin olive oil from young trees olea europaea l cv arbequina grown under linear irrigation strategies
    Journal of Agricultural and Food Chemistry, 2001
    Co-Authors: M J Tovar, Maria-josé Motilva, Maria-paz Romero
    Abstract:

    This study reports the HPLC profiles of phenolic compounds of virgin olive oils obtained from young olive trees (Olea europaea L. cv. Arbequina) and how the application of a linear irrigation strategy affected these. Hydroxytyrosol, tyrosol, vanillic Acid, vanillin, 4-(acetoxyethyl)-1,2-dihydroxybenzene, p-coumaric Acid, the dialdehydic form of Elenolic Acid linked to hydroxytyrosol and to tyrosol, lignans, and the oleuropein aglycon were found in all the oils. Hydroxytyrosol, tyrosol, vanillic Acid, and p-coumaric Acid contents in the oils were unaffected by linear irrigation. The concentration of lignans was lower in the oils from the least irrigated treatment and the concentration of vanillin increased as the amount of irrigation water applied to olive trees increased. However, 4-(acetoxyethyl)-1,2-dihydroxybenzene, the dialdehydic form of Elenolic Acid linked to hydroxytyrosol and to tyrosol, and the oleuropein aglycon, all of them hydroxyphenyl derivatives, decreased as the level of irrigation water ...

  • changes in the phenolic composition of virgin olive oil from young trees olea europaea l cv arbequina grown under linear irrigation strategies
    Journal of Agricultural and Food Chemistry, 2001
    Co-Authors: M J Tovar, Maria-josé Motilva, M P Romero
    Abstract:

    This study reports the HPLC profiles of phenolic compounds of virgin olive oils obtained from young olive trees (Olea europaea L. cv. Arbequina) and how the application of a linear irrigation strategy affected these. Hydroxytyrosol, tyrosol, vanillic Acid, vanillin, 4-(acetoxyethyl)-1,2-dihydroxybenzene, p-coumaric Acid, the dialdehydic form of Elenolic Acid linked to hydroxytyrosol and to tyrosol, lignans, and the oleuropein aglycon were found in all the oils. Hydroxytyrosol, tyrosol, vanillic Acid, and p-coumaric Acid contents in the oils were unaffected by linear irrigation. The concentration of lignans was lower in the oils from the least irrigated treatment and the concentration of vanillin increased as the amount of irrigation water applied to olive trees increased. However, 4-(acetoxyethyl)-1,2-dihydroxybenzene, the dialdehydic form of Elenolic Acid linked to hydroxytyrosol and to tyrosol, and the oleuropein aglycon, all of them hydroxyphenyl derivatives, decreased as the level of irrigation water increased. The latter three compounds represented the most considerable part of the phenolic fraction of the oils and they were shown to be correlated to the oxidative stability, the bitter index (K(225)), and the bitter, pungent, and sweet sensory attributes. Linear irrigation strategy changed the profile of the oil phenolic compounds and, therefore, changed both the organoleptic properties and the antioxidant capacity of the product.

Antonio Segura-carretero - One of the best experts on this subject based on the ideXlab platform.

  • Preliminary Investigation of Different Drying Systems to Preserve Hydroxytyrosol and Its Derivatives in Olive Oil Filter Cake Pressurized Liquid Extracts
    'MDPI AG', 2021
    Co-Authors: Lucía López-salas, Inés Cea, Isabel Borrás-linares, Tatiana Emanuelli, Paz Robert, Antonio Segura-carretero, Jesús Lozano-sánchez
    Abstract:

    Phenolic compounds present in extra virgin olive oil (EVOO) could be retained in its byproducts during processing. Among them, hydroxytyrosol and its derivatives deserve special attention due to their health benefits recognized by The European Food Safety Authority (EFSA). In the present research, the presence of these compounds in the filter cake byproduct was studied by combining pressurized liquid extraction (PLE) and high-performance liquid chromatography coupled to time-of-flight mass spectrometry (HPLC-TOF-MS). The applied optimum extraction parameters were 1500 psi, 120 °C and aqueous ethanol (50:50, v/v). The influence of different drying methods (vacuum-, freeze- and spray-drying) in the recovery of phenolic compounds was also evaluated. A total of 16 compounds from EVOO were identified in the extracts, 3 of them being hydroxytyrosol-related compounds, 6 substances of oleoside and Elenolic Acid derivatives, together with 6 secoiridoids and 1 lignan. The results highlighted the great number of phenolic compounds recovered from filter cake with these techniques, being even higher than the reported content in EVOO and other byproducts. The combination of PLE and freeze-drying resulted in being the best procedure for the recovery of phenolic compounds from filter cake byproduct

  • tabAnti-HER2 (erbB-2) oncogene effects of phenolic compounds directly isolated from commercial Extra-Virgin Olive Oil (EVOO)
    BMC Cancer, 2008
    Co-Authors: Javier A Menendez, Alejandro Vazquez-martin, Rocio Garcia-villalba, Alegria Carrasco-pancorbo, Cristina Oliveras-ferraros, Alberto Fernandez-gutierrez, Antonio Segura-carretero
    Abstract:

    Background The effects of the olive oil-rich Mediterranean diet on breast cancer risk might be underestimated when HER2 ( ERB B2) oncogene-positive and HER2-negative breast carcinomas are considered together. We here investigated the anti-HER2 effects of phenolic fractions directly extracted from Extra Virgin Olive Oil (EVOO) in cultured human breast cancer cell lines. Methods Solid phase extraction followed by semi-preparative high-performance liquid chromatography (HPLC) was used to isolate phenolic fractions from commercial EVOO. Analytical capillary electrophoresis coupled to mass spectrometry was performed to check for the composition and to confirm the identity of the isolated fractions. EVOO polyphenolic fractions were tested on their tumoricidal ability against HER2-negative and HER2-positive breast cancer in vitro models using MTT, crystal violet staining, and Cell Death ELISA assays. The effects of EVOO polyphenolic fractions on the expression and activation status of HER2 oncoprotein were evaluated using HER2-specific ELISAs and immunoblotting procedures, respectively. Results Among the fractions mainly containing the single phenols hydroxytyrosol and tyrosol, the polyphenol Acid Elenolic Acid, the lignans (+)-pinoresinol and 1-(+)-acetoxypinoresinol, and the secoiridoids deacetoxy oleuropein aglycone, ligstroside aglycone, and oleuropein aglycone, all the major EVOO polyphenols ( i.e. secoiridoids and lignans) were found to induce strong tumoricidal effects within a micromolar range by selectively triggering high levels of apoptotic cell death in HER2-overexpressors. Small interfering RNA-induced depletion of HER2 protein and lapatinib-induced blockade of HER2 tyrosine kinase activity both significantly prevented EVOO polyphenols-induced cytotoxicity. EVOO polyphenols drastically depleted HER2 protein and reduced HER2 tyrosine autophosphorylation in a dose- and time-dependent manner. EVOO polyphenols-induced HER2 downregulation occurred regardless the molecular mechanism contributing to HER2 overexpression ( i.e . naturally by gene amplification and ectopically driven by a viral promoter). Pre-treatment with the proteasome inhibitor MG132 prevented EVOO polyphenols-induced HER2 depletion. Conclusion The ability of EVOO-derived polyphenols to inhibit HER2 activity by promoting the proteasomal degradation of the HER2 protein itself, together with the fact that humans have safely been ingesting secoiridoids and lignans as long as they have been consuming olives and OO, support the notion that the stereochemistry of these phytochemicals might provide an excellent and safe platform for the design of new HER2-targeting agents.

Jose G Fernandezbolanos - One of the best experts on this subject based on the ideXlab platform.

  • isolation and characterization of a secoiridoid derivative from two phase olive waste alperujo
    Journal of Agricultural and Food Chemistry, 2015
    Co-Authors: Fatima Rubiosenent, Aranzazu Garcia, Sergio Martos, Jose G Fernandezbolanos, Guillermo Rodriguezgutierrez
    Abstract:

    A secoiridoid derivative was isolated from the ethyl acetate extract of two-phase olive waste (alperujo). The structure of this compound was fully characterized as s-trans-(E)-3-(1-oxobut-2-en-2-yl)glutaric Acid. The spectroscopic data, including one- and two-dimensional nuclear magnetic resonance, mass spectrometry, infrared analysis, and ultraviolet spectrum, were showed. The origin of this compound has not been previously studied, although it most likely results from the breakdown of the oleuropein (or ligstroside) secoiridoid skeleton via oxidation and decarboxylation of the dialdehydic form of Elenolic Acid, with this transformation being enhanced by extraction of phenolics with ethyl acetate. In addition, the bactericidal activity of (E)-3-(1-oxobut-2-en-2-yl)glutaric Acid and extracts containing it was evaluated against two phytopatoghenic microorganisms Pseudomonas syringae and Agrobacterium tumefaciens.

Vázquez-roncero A. - One of the best experts on this subject based on the ideXlab platform.

  • Glucósidos fenólicos amargos de las semillas del olivo (olea europaea)
    CSIC - Instituto de la Grasa (IG), 2021
    Co-Authors: Maestro Durán R., León Cabello R., Ruiz-gutiérrez Valentina, Fiestas P., Vázquez-roncero A.
    Abstract:

    [EN]: Bitter phenolic glucosides from seeds of olive (Olea europaea). From the seeds of Olea e uropa ea, three known glucosides, salidroside (tyrosol-glucose), nüzhenide (glucose-Elenolic Acid-glucose- tyrosol) and nüzhenide-oleoside have been isolated as well as two new secoiridoid glucosides with tyrosol, Elenolic Acid and glucose moieties in unknown sequence.[ES]: Glucósidos fenólicos amargos de las semillas del olivo (Olea europaea). Se han aislado de semillas de aceituna (Olea europaea) tres glucósi- dos secoiridoides ya conocidos: salidrósído (tirosol-glucosa), nuzhenida (glucosa-ácido elenólico-glucosa-tirosol) y nuzhenida-oleósido, así como otros dos glucósidos secoiridoides que también tienen en su molécula tirosol, ácido elenólico y glucosa cuyas secuencias no se han podido establecer

  • Bitter phenolic glucosides from seeds of olive (Olea europaea )
    'Editorial CSIC', 1994
    Co-Authors: Maestro Durán R., León Cabello R., Ruiz-gutiérrez Valentina, Fiestas P., Vázquez-roncero A.
    Abstract:

    4 páginas, 2 figuras.[ES] Se han aislado de semillas de aceituna (Olea europaea ) tres glucósidos secoiridoides ya conocidos: salidrósido (tirosol-glucosa), nuzhenida (glucosa-ácido elenólico-glucosa-tirosol) y nuzhenida-oleósido, así como otros dos glucósidos secoiridoides que también tienen en su molécula tirosol, ácido elenólico y glucosa cuyas secuencias no se han podido establecer.[EN] From the seeds of Olea europaea, three known glucosides, salidroside (tyrosol-glucose), nüzhenide (glucose-Elenolic Acid-glucosetyrosol) and nüzhenide-oleoside have been isolated as well as two new secoiridoid glucosides with tyrosol, Elenolic Acid and glucose moieties in unknown sequence.Peer reviewe

  • Glucósidos fenólicos amargos de las semillas del olivo (<i>Olea europea</i>)
    Consejo Superior de Investigaciones Científicas, 1994
    Co-Authors: Maestro Durán R., León Cabello R., Fiestas P., Vázquez-roncero A.
    Abstract:

    From the seeds of <i>Olea europaea</i>, three known glucosides, salidroside (tyrosol-glucose), nüzhenide (glucose-Elenolic Acid-glucosetyrosol) and nüzhenide-oleoside have been isolated as well as two new secoiridoid glucosides with tyrosol, Elenolic Acid and glucose moieties in unknown sequence.<br><br>Se han aislado de semillas de aceituna (<i>Olea europaea</i> ) tres glucósidos secoiridoides ya conocidos: salidrósido (tirosol-glucosa), nuzhenida (glucosa-ácido elenólico-glucosa-tirosol) y nuzhenida-oleósido, así como otros dos glucósidos secoiridoides que también tienen en su molécula tirosol, ácido elenólico y glucosa cuyas secuencias no se han podido establecer

M P Romero - One of the best experts on this subject based on the ideXlab platform.

  • changes in the phenolic composition of virgin olive oil from young trees olea europaea l cv arbequina grown under linear irrigation strategies
    Journal of Agricultural and Food Chemistry, 2001
    Co-Authors: M J Tovar, Maria-josé Motilva, M P Romero
    Abstract:

    This study reports the HPLC profiles of phenolic compounds of virgin olive oils obtained from young olive trees (Olea europaea L. cv. Arbequina) and how the application of a linear irrigation strategy affected these. Hydroxytyrosol, tyrosol, vanillic Acid, vanillin, 4-(acetoxyethyl)-1,2-dihydroxybenzene, p-coumaric Acid, the dialdehydic form of Elenolic Acid linked to hydroxytyrosol and to tyrosol, lignans, and the oleuropein aglycon were found in all the oils. Hydroxytyrosol, tyrosol, vanillic Acid, and p-coumaric Acid contents in the oils were unaffected by linear irrigation. The concentration of lignans was lower in the oils from the least irrigated treatment and the concentration of vanillin increased as the amount of irrigation water applied to olive trees increased. However, 4-(acetoxyethyl)-1,2-dihydroxybenzene, the dialdehydic form of Elenolic Acid linked to hydroxytyrosol and to tyrosol, and the oleuropein aglycon, all of them hydroxyphenyl derivatives, decreased as the level of irrigation water increased. The latter three compounds represented the most considerable part of the phenolic fraction of the oils and they were shown to be correlated to the oxidative stability, the bitter index (K(225)), and the bitter, pungent, and sweet sensory attributes. Linear irrigation strategy changed the profile of the oil phenolic compounds and, therefore, changed both the organoleptic properties and the antioxidant capacity of the product.