Search results for "Olive oil"
showing 10 items of 194 documents
Nutraceutical properties of extra-virgin olive oil: a natural remedy for age-related disease?
2013
The health benefits of the Mediterranean diet can be largely ascribed to the nutraceutical properties of extra-virgin olive oil (EVOO). Mono-unsaturated fatty acids and various phenolic compounds, such as oleocanthal, oleuropein, hydroxytyrosol, and tyrosol, are the main nutraceutical substances of EVOO. These substances have been suggested to have the ability to modulate aging-associated processes. In experimental models, it has been shown that EVOO with high concentrations of polyphenols has anti-inflammatory and anti-oxidant properties. Indeed, it was observed that hydroxytyrosol and oleocanthal inhibit the cyclooxygenases (COX-1 and -2) responsible for prostaglandin production; oleurope…
Mediterranean Diet and Cardiovascular Health: Teachings of the PREDIMED Study123
2014
The PREDIMED (Prevención con Dieta Mediterránea) study was designed to assess the long-term effects of the Mediterranean diet (MeDiet) without any energy restriction on incident cardiovascular disease (CVD) as a multicenter, randomized, primary prevention trial in individuals at high risk. Participants were randomly assigned to 3 diet groups: 1) MeDiet supplemented with extra-virgin olive oil (EVOO); 2) MeDiet supplemented with nuts; and 3) control diet (advice on a low-fat diet). After 4.8 y, 288 major CVD events occurred in 7447 participants; crude hazard ratios were 0.70 (95% CI: 0.53, 0.91) for the MeDiet + EVOO and 0.70 (95% CI: 0.53, 0.94) for the MeDiet + nuts compared with the contr…
Development of Methods for the Evaluation of Olive Oil Oxidation
2012
In this work, the chemical changes produced in an EVOO sample, both in the presence and absence of its phenolic fraction during an accelerated ageing treatment have been studied. The changes produced in phenolic compound concentrations, jointly with the changes observed in free acidity, peroxide value, UV absorbance, fatty acid composition, OSI and T content, were monitored. In addition, transformation of phenolic compounds during the accelerated ageing treatment in EVOO samples with phenolic fraction was also studied.
Protection by extra virgin olive oil against oxidative stress in vitro and in vivo. Chemical and biological studies on the health benefits due to a m…
2017
Abstract We report the results of in vivo studies in Caenorhabditis elegans nematodes in which addition of extra virgin olive oil (EVOO) to their diet significantly increased their life span with respect to the control group. Furthermore, when nematodes were exposed to the pesticide paraquat, they started to die after two days, but after the addition of EVOO to their diet, both survival percentage and lifespans of paraquat-exposed nematodes increased. Since paraquat is associated with superoxide radical production, a test for scavenging this radical was performed using cyclovoltammetry and the EVOO efficiently scavenged the superoxide. Thus, a linear correlation (y = -0.0838x +19.73, regres…
Phenolic Compounds Characterization and Antioxidant Properties of Monocultivar Olive Oils from Northeast Algeria
2020
In Algeria, the olive tree is one of the main fruit species and plays a very important socioeconomic role. The objective of this study was firstly, to identify and quantify the phenolics of some Algerian olive oils, and secondly, to assess the antioxidant activity of the samples. The olive oils used in this study were derived from Algerian cultivars, including Tefahi, Gelb Elfarroudj, Chemlal, and imported cultivar Manzanilla and Zebboudj. For this purpose, gas chromatography&mdash
Oxidative stability of virgin olive oils
2001
An investigation was carried out on virgin olive oils of the Gentile (Larino), Gentile (Colletorto), Coratina, and Leccino varieties, harvested at different times, to assess their oxidation stability. The olive oils were analyzed by means of peroxide, K-232, and K 270 values at 1, 6, 12, and 18 mon of storage in green bottles, in the dark, at temperatures ranging from a mean of 6degreesC in winter to 12degreesC in summer. A subsample was also oven-tested at 75degreesC and then analyzed on a weekly basis using the same oxidative parameters. The less ripe the olives (harvested in the same area, during 1 mon), the more resistant the olive oils were to forced oxidation. The amount of total phen…
Alternariol-induced cytotoxicity in Caco-2 cells. Protective effect of the phenolic fraction from virgin olive oil.
2014
The extra virgin olive oil (EVOO) has been associated to antioxidant effects. The mycotoxin alternariol (AOH) can contaminate olives. The aims of this work were to determine the cytotoxic effects and reactive oxygen species (ROS) produced by AOH, tyrosol and oleuropein (two polyphenols of olive oil) and a real EVOO extract in Caco-2 cells. The MTT assay and the ROS production by the H2-DCFDA probe were used. Results demonstrated that AOH reduces cellular proliferation depending on concentration, whereas tyrosol and oleuropein did not (12.5-100 μM). The combination of AOH + oleuropein (50 μM) increased cell proliferation (24%) whereas, AOH + tyrosol decreased (47%) it. Besides, AOH increased…
Influence of cultivar and concentration of selected phenolic constituents on the in vitro chemiopreventive potential of olive oil extracts.
2011
One of the main olive oil phenolic compounds, hydroxytyrosol (3,4-DHPEA), exerts in vitro chemopreventive activities (antiproliferative and pro-apoptotic) on tumor cells through the accumulation of H2O2 in the culture medium. However, the phenol composition of virgin olive oil is complex, and 3,4-DHPEA is present at low concentrations when compared to other secoiridoids. In this study, the in vitro chemopreventive activities of complex virgin olive oil phenolic extracts (VOO-PE, derived from the four Italian cultivars Nocellara del Belice, Coratina, Ogliarola, and Taggiasca) were compared to each other and related to the amount of the single phenolic constituents. A great chemopreventive po…
Gas assisted mechanical expression (GAME) for the selective recovery of lipophilic and hydrophilic compounds from olive kernel
2017
Abstract This work is devoted to valorize olive kernel; a by-product produced during olive oil extraction process. For this purpose, aqueous liquid solid extraction (LSE), mechanical expression (ME), supercritical CO2 (SC-CO2) and gas assisted mechanical expression (GAME), processes were compared when applied separately or consequently (ME + GAME), in terms of total phenolic compound (TPC) and oil recovery yields. Results showed that although the high extraction yields of TPC using LSE (61.4 ± 1.3%), the extraction process is economically not viable. However, it was demonstrated that applying ME (1 h at 30 MPa) followed by GAME (1 h at 30 MPa ME and 10 MPa SC-CO2 pressures) allowed recoveri…
Chemical characterization of organic residues on Late Roman amphorae from shipwrecks off the coast of Marsala (Trapani, Italy)
2021
Abstract Organic residues were extracted from thirty-three different types of Roman and Late Antique amphorae retrieved from underwater contexts in the custody of the Archaeological Museum “Baglio Anselmi” of Marsala in Sicily. The samples were analysed using GC-MS and 1H NMR, finding biomarkers of plant oils (including saturated and unsaturated fatty acids, alcohols and alkanes present in plant waxes) were identified in seven samples. The biomarkers for Pinaceae spp., used for making pitch, were identified in one sample. The results obtained shed light on the function of different types of North African amphorae, traditionally interpreted as containers for olive oil, wine and fish sauce, p…