Search results for "hydroxytyrosol"
showing 10 items of 34 documents
Oleuropein ameliorates acute colitis in mice.
2011
Oleuropein, the major secoiridoid in olive tree leaves, possesses a wide range of health promoting properties. It has recently been shown to exhibit anti-inflammatory activity. We have evaluated the effect of oleuropein on dextran sulfate sodium (DSS)-induced experimental colitis in mice in order to provide insight into its mechanisms of action. Oral administration of oleuropein notably attenuated the extent and severity of acute colitis while reducing neutrophil infiltration; production of NO, IL-1β, IL-6, and TNF-α; expression of iNOS, COX-2, and MMP-9; and the translocation of the NF-κB p65 subunit to the nucleus in colon tissue. In LPS-stimulated peritoneal macrophages, the oleuropein m…
Effect of storage on quality parameters and phenolic content of Italian extra-virgin olive oils
2019
The quality of extra virgin olive oils is affected mainly by hydrolytic and oxidative reactions. The present paper investigated the changes of major and minor components and oxidation indices of three monovarietal extra virgin olive oils after 18 months of storage at room temperature and in dark glass bottles conditions. After storage, the basic quality parameters such as free acidity, peroxide values, extinction coefficients, fatty acids composition, chlorophyll and carotenoid content, did not exceed the upper limits set by European Community Regulations for extra-virgin olive oils. Given the importance of the phenolic fraction, UHPLC-HESI-MS metodology was used. A decrease in 3,4-DHPEA-ED…
C18 alkyl-modified silica: A suitable tool for olive biophenol green extraction
2017
Abstract A clean and straightforward methodology to assess the value of olive mill wastewater (OMWW) samples as well as to obtain biophenol-rich oils that can find employment in a variety of cosmetic, nutraceutical and pharmaceutical products is described. The method employs chromatographic spherical organosilica microparticles, coupled to advanced analytical techniques. OMWW samples obtained in Sicily from two different organically grown cultivars during the exceptional 2015/2016 olive oil season were analyzed, leading us to establish the conditions for optimal extraction of hydroxytyrosol and tyrosol.
A new By-Product enriched in phenolic compounds, evaluated by UHPLC-HRMS, from olive mill wastewater
Quick assessment of the economic value of olive mill waste water
2016
Background: Olive biophenols are emerging as a valued class of natural products finding practical application in the food, pharmaceutical, beverage, cosmetic and nutraceutical industries due to their powerful biological activity which includes antioxidant and antimicrobial properties. Olive mill waste water (OMWW), a by-product in olive oil manufacturing, is rich in biophenols such as hydroxytyrosol and tyrosol. The amount of biophenols depends on the cultivar, the geographical area of cultivation, and the seasonal conditions. The goal of this study was to develop a straightforward method to assess the economic value of OMWW via quantification of hydroxytyrosol and tyrosol. Results: The amo…
Antiproliferative and proapoptotic activities of hydroxytyrosol derivatives on human promyelocytic leukemia cell lines
2012
Purpose Hydroxytyrosol (3,4-DHPEA) derivatives (disulfide, thioacetate and thiohydroxytyrosol) were synthesized in order to test in vitro if the combination of catechol moiety of 3,4-DHPEA and sulfur containing functions results in an improvement of the pro-apoptotic and anti-proliferative activities shown by 3,4-DHPEA. The involvement of H2O2 production in the cell culture medium has been studied. Methods The effects of thiohydroxytyrosol derivatives and 3,4-DHPEA on cell proliferation, apotosis and cell cycle of HL60 and its MDR variant HL60R were assessed by the Trypan Blue exclusion test, by fluorescence microscopy or by flow cytometry respectively. H2O2 concentrations in the culture me…
Effects of Oleuropein and Hydroxytyrosol on Inflammatory Mediators: Consequences on Inflammaging
2022
Aging is associated with a low-grade, systemic inflammatory state defined as “inflammaging”, ruled by the loss of proper regulation of the immune system leading to the accumulation of pro-inflammatory mediators. Such a condition is closely connected to an increased risk of developing chronic diseases. A number of studies demonstrate that olive oil phenolic compound oleuropein and its derivative hydroxytyrosol contribute to modulating tissue inflammation and oxidative stress, thus becoming attractive potential candidates to be used in the context of nutraceutical interventions, in order to ameliorate systemic inflammation in aging subjects. In this review, we aim to summarize the available d…
Anti-Inflammatory Effects of Nutritionally Relevant Concentrations of Oleuropein and Hydroxytyrosol on Peripheral Blood Mononuclear Cells: An Age-Rel…
2023
: Immunosenescence and inflammaging facilitate the insurgence of chronic diseases. The Mediterranean diet is a non-invasive intervention to improve the chronic low-grade inflammatory status associated with aging. Olive oil oleuropein (OLE) and hydroxytyrosol (HT) demonstrated a controversial modulatory action on inflammation in vitro when tested at concentrations exceeding those detectable in human plasma. We studied the potential anti-inflammatory effects of OLE and HT at nutritionally relevant concentrations on peripheral blood mononuclear cells (PBMCs) as regards cell viability, frequency of leukocyte subsets, and cytokine release, performing an age-focused analysis on two groups of subj…
Assessment of the antioxidant and antibacterial activities of different olive processing wastewaters.
2017
Olive processing wastewaters (OPW), namely olive mill wastewater (OMW) and table-olive wastewaters (TOW) were evaluated for their antibacterial activity against five Gram-positive and two Gram-negative bacteria using the standard disc diffusion and thin layer chromatography (TLC)-bioautography assays. Disc diffusion screening and bioautography of OMW were compared to the phenolic extracts of table-olive brines. Positive activity against S. aureus was demonstrated. The optimization of chromatographic separation revealed that hexane/acetone in the ratio of 4:6 was the most effective for phenolic compounds separation. A HPLC-MS analysis was performed showing that only two compounds, hydroxytyr…
Bioreactivity of Resveratrol Toward Inflammation Processes
2014
Grape polyphenols are abundant. They play essential roles in the vine’s life, particularly in its defense mechanisms. Interestingly, the grape, fresh or dried, is a widely consumed fruit by humans, as are its processed products, grape juice and wine. Moreover, they contain vast and highly varied quantities of polyphenols. Like other phytophenols, grape and wine resveratrol is considered a protective micronutrient like flavonoids, epicatechins in green tea and cocoa, quercetin in apples and onions, curcumin of the turmeric root, and hydroxytyrosol in olive oil. Resveratrol is a powerful natural antioxidant in vine. Interestingly, in humans, it protects low density lipoproteins against oxidat…