Search Results (958)

Background: The global increase in life expectancy has led to a higher prevalence of age-related cognitive decline, highlighting the need for effective non-pharmacological interventions. This systematic review aimed to evaluate the potential effects of olive oil, particularly its bioactive compounds and fatty acid profile, on cognitive function in adults Methods: A comprehensive literature search was conducted in PubMed, Scopus, and EBSCO in accordance with PRISMA 2020 guidelines, including peer-reviewed studies published in English between 2015 and 2025. A total of six studies met the inclusion criteria and were included in the final qualitative synthesis, comprising five randomized controlled trials and one prospective cohort study. Risk of bias was assessed using the Cochrane Risk of Bias tool (RoB 2) and the Newcastle–Ottawa Scale. Results: The findings suggest that consumption of extra virgin olive oil (EVOO), particularly high-phenolic varieties, may be associated with improvements in cognitive domains such as memory, attention, executive function, and global cognition. However, the evidence is derived from a limited number of heterogeneous studies with relatively small sample sizes. Most of the available data relate to high-phenolic EVOO and olive-derived bioactive compounds, while studies directly examining the role of fatty acid composition remain limited. Proposed mechanisms include reduced blood–brain barrier permeability, enhanced brain functional connectivity, and the neuroprotective effects of compounds such as hydroxytyrosol and oleuropein. Conclusions: While the findings suggest potential cognitive benefits of EVOO, the current evidence remains preliminary and insufficient to establish causality. Therefore, results should be interpreted with caution. Further large-scale, well-designed randomized controlled trials are required to confirm these associations and clarify the specific contributions of fatty acids and bioactive compounds. Full article

Hydroxymethylfurfural (HMF) is a well-established marker of heat-induced reactions in sugar-rich foods. However, its accumulation in raisins in response to clean-label pretreatments and its association with consumer sensory perception remain unclear. This study investigated the influence of extra virgin olive oil (EVOO) pretreatment, cultivar (BRS Clara and BRS Vitoria), and storage conditions (4, 25, and 35 °C) on HMF formation in raisins and on their sensory implications. Cultivar influenced physicochemical properties, but neither cultivar nor pretreatment significantly affected HMF levels after drying. During storage, HMF formation followed predominantly zero-order reaction kinetics, with Q10 values (7.33–8.39) confirming strong temperature dependence, and pronounced accumulation at 35 °C. Sensory analysis showed that flavor was the main driver of consumer perception, with burnt sugar notes more frequently cited as a disliked attribute in samples stored at higher temperatures, whereas samples stored at lower temperatures retained attributes closer to time zero. Pearson correlation analysis confirmed a strong positive association between HMF and the burnt sugar descriptor (r = 0.86, p < 0.001). These findings demonstrate that EVOO pretreatment can improve drying efficiency without promoting HMF formation, and highlight the value of the combined chemical–sensory approach to assess quality changes in raisins from tropical-adapted grape cultivars. Full article

This study aimed to evaluate the effects of several minor components of extra virgin olive oil (EVOO) on platelet thromboxane and vascular prostacyclin production in rat aortic rings under high-glucose conditions (300 mg/dL), in relation to their potential antioxidant actions. Under hyperglycaemic conditions, thromboxane production was 1.3 times higher, while prostacyclin production was 40.9% lower than in samples with 100 mg/dL glucose in aortic rings, accompanied by marked oxidative stress (65.6% higher than in samples with 100 mg/dL glucose). The compounds tested inhibited thromboxane production in a concentration-dependent manner, with relative potencies (secoiridoid derivatives (IC₅₀ range: 10⁻⁶ M) = triterpenes (10⁻⁶ M) > alcoholic phenols (10⁻⁵ M for hydroxytyrosol and 10⁻⁴ M for the rest)), while preserving prostacyclin production (5–20% inhibition). All compounds also exerted vascular antioxidant effects, reducing oxidative stress markers and enhancing antioxidant parameters (IC₅₀ range: 10⁻⁶–10⁻⁵ M), and these effects were observed under both normoglycaemic (100 mg/dL) and hyperglycaemic (300 mg/dL) conditions. Full article

Background/Objectives: Lipid oxidation is a major factor limiting the shelf life and nutritional quality of edible vegetable oils. Enhancing the oxidative stability of extra virgin olive oil (EVOO) through natural antioxidants is of increasing interest to both industry and consumers. This study aimed to evaluate the impact of five plant-derived essential oils (orange, lemon, black pepper, oregano, and rosemary) incorporated at three concentrations (0.5, 1, and 2% w/w) on the oxidative stability, antioxidant capacity, and bioactive compound retention of EVOO. Methods: All fortified EVOO samples were stored at 60 °C for 28 days to simulate accelerated oxidation. A positive control containing 200 ppm of butylated hydroxytoluene (BHT) was included for comparison. Oxidative stability was assessed through peroxide value, TBARS, p-anisidine value, and conjugated dienes/trienes. Tocopherols, carotenoids, and chlorophylls were quantified, while radical scavenging activity was determined using Trolox-equivalent assays. Correlation analyses were performed to explore relationships between essential oil composition and antioxidant performance. Results: Among the tested essential oils, oregano at 2% demonstrated the strongest protective effect, reducing both primary and secondary oxidation products and yielding a Totox value (34.26) close to that of the BHT-enriched control (29.86) after 28 days. Regarding long-term radical scavenging capacity, rosemary at 1% concentration provided the closest activity to BHT (402.89 vs. 536.64 μM Trolox equivalents). Both oregano and rosemary enhanced the preservation of α-tocopherol, likely due to the activity of key constituents such as carvacrol and 1,8-cineole. Conclusions: The incorporation of selected essential oils, particularly oregano and rosemary, can effectively enhance the oxidative stability and antioxidant capacity of EVOO, supporting their potential use as natural alternatives to synthetic antioxidants. Full article

Landmark epidemiological studies and clinical trials, such as the Seven Countries Study, the Lyon Diet Heart Study, the PREDIMED Study and the CORDIOPREV Study, have shown significant reductions in cardiovascular events in those following the Mediterranean diet (MD). The aim of the present work is to summarize the most robust available evidence and the major biological pathways underlying the protective effects of the MD, with particular emphasis on the role of PAF inhibitors. Mechanistically, MD functions through a complex synergy of antioxidant, anti-inflammatory, and antithrombotic effects that collectively improve lipid profiles, enhance endothelial function, optimize postprandial metabolism and cell membrane signaling, making it a functional model for human longevity. The PAF-Implicated Atherosclerosis Theory has emerged as a key unifying framework, proposing that Platelet-Activating Factor (PAF)—a highly potent lipid inflammatory mediator—plays a central role in the initiation and progression of atherosclerosis. Oxidized LDL promotes the production of PAF and PAF-like lipids, leading to endothelial dysfunction, vascular inflammation, and atherosclerotic plaque formation. Traditional Mediterranean foods are rich in natural PAF inhibitors, particularly the polar lipid fractions of extra virgin olive oil, as well as wine, fish, vegetables, onions, and garlic. Animal studies demonstrate that these compounds can reduce or even regress atherosclerotic lesions, independently of serum cholesterol levels. Human dietary interventions have further shown that MD-based meals and functional foods enriched with PAF inhibitors reduce PAF activity and improve thrombosis-related biomarkers. This mechanistic framework helps explain phenomena such as the “French Paradox” and the cardio-protective effects associated with fish consumption. Moreover, the extraction of PAF inhibitors from Mediterranean food by-products, such as olive pomace, offers promising ecological and economic advantages. Collectively, targeting PAF and increasing dietary intake of PAF inhibitors represent promising strategies for the prevention and management of atherosclerosis and other inflammatory diseases, supporting the view that PAF may function as a major, modifiable risk factor in these conditions. Full article

Olive tree (Olea europaea L.) is a major Mediterranean crop, valued for both fruit yield and high-quality oil, yet extreme summer stress, including high temperature, intense irradiance, and water limitation, can substantially reduce productivity and affect oil composition. The objective of the present study was to evaluate the mitigating efficacy of foliar applications of glycine betaine (GB), kaolin (K), and calcium carbonate (CC) under rainfed conditions across three Greek sites on “Koroneiki” (in two sites) and “Lianolia Kerkyras” (in one site) cultivars. Treatments were applied during the summer, and effects on fruit yield, oil content per fruit, oil yield per tree, and key oil quality parameters—including total phenols, flavonoids, antioxidant capacity, and fatty acid composition—were assessed. GB significantly enhanced fruit yield and oil production for “Koroneiki” at the site with the harshest environmental conditions (24.37 kg fruits per tree and 4.69 kg of oil per tree compared to 19.16 kg fruits per tree and 3.48 kg of oil per tree in control). In contrast, K proved most effective at the other two sites for both cultivars (43% and 52.8% increase in fruit yield and oil mass per tree in “Koroneiki” respectively and 30% as well as 34% increase in yield and oil mass per tree in “Lianolia Kerkyras”, respectively. CC exhibited limited impact on both productivity and quality. Under all treatments, the oils produced could be classified as extra virgin olive oils, with the products exhibiting minor effects on the functional properties of the oils. These findings indicate that the efficacy of stress-alleviating foliar treatments is strongly influenced by both environmental conditions and cultivar. Overall, K was the most effective treatment, followed by GB. Tailored application of these treatments represents a sustainable approach to maintaining olive productivity and preserving oil quality in the context of climate change. Full article

The European Regulation (UE) 432/2012 includes a specific health claim for olive-oil-associated with its phenolic content, which is based on its protective role against lipid oxidation in the blood. To make use of the health claim, olive oil must have a minimum concentration in phenolic compounds of 250 mg/kg. Reviewing the health claim, the phenolic compounds referred to are the secoiridoid derivatives of hydroxytyrosol and tyrosol. A method based on absolute quantification of phenolic compounds in olive oil is proposed for the recognition of the health claim. The method involves liquid–liquid extraction with a 1:8 (v/v) oil:extract ratio to avoid saturation of the extract in oils with a higher phenolic content and its subsequent determination through LC–MS/MS in multiple reaction monitoring (MRM) mode, the gold standard technique in many application fields because of its analytical features. The optimized method was applied to a set of 100 extra virgin olive oils (EVOOs), and the results obtained were compared with the classic Folin–Ciocalteu method. The comparison between the two methods showed that the classic method is a non-selective method that can be affected by many interferences and that the Folin method underestimates the real phenolic content. Full article

Climate change-induced abiotic stress, particularly heat and drought during olive oil accumulation, significantly threatens the productivity and oil quality of olive trees (Olea europaea L.). This study investigated the efficacy of pre-harvest elicitation using the biostimulants harpin and chitosan (both as commercially available products) under summer conditions in Greece, in commercially productive rainfed groves of cv. ‘Megaritiki’. Multivariate analysis (PCA and factor analysis) revealed that pre-harvest application of these elicitors successfully balanced the trade-off between oil yield and quality. Both harpin and chitosan maintained hydrolytic (free acidity—0.25 and 0.29 g oleic acid 100 g⁻¹, respectively, compared to 0.56 g oleic acid 100 g⁻¹ in the control) and primary oxidative markers (peroxides—4.16 and 4.16 meq O₂ kg⁻¹, respectively, compared to 5.20 meq O₂ kg⁻¹ in the control) at exceptionally low levels compared to untreated trees. The treatments induced a distinctive metabolic shift regarding volatile compounds governed by the lipoxygenase (LOX) pathway. Harpin application was strongly associated with complex floral and fruity volatile compounds (2-hexen-1-ol and trans-2-hexenal) and a high α-tocopherol concentration (38.58 mg kg⁻¹ compared to 23.12 mg kg⁻¹ in the control), suggesting an enhanced physiological response in favor of oil quality attributes. Conversely, chitosan elevated the oxidative stability of the oil by increasing total phenol concentration (by almost 97% compared to the control) and prioritizing the accumulation of the stable monounsaturated fatty acids (oleic acid—increased by 12.5% compared to the control) over polyunsaturated ones (linoleic acid), while endowing the oil with desirable “green freshness” aromas (cis-3-hexenal). These results demonstrate that elicitation with harpin and chitosan is a potent tool for sustainably enhancing extra virgin olive oil quality under rainfed conditions in Greece, steering fruit metabolism toward a premium nutraceutical and sensory profile and enhancing the functional properties of the oil (phenol content, antioxidant capacity, monounsaturated fatty acids, α-tocopherol and squalene). Full article

Mineral oil hydrocarbons (MOH), comprising saturated (MOSH) and aromatic (MOAH) compounds, are ubiquitous lipophilic contaminants. This review critically examines their occurrence, toxicology, analysis, contamination sources, and mitigation strategies in the olive oil sector. Emphasis is placed on analytical evolution, highlighting online LC-GC-FID and the EN ISO 20122:2024 standard, including advances in saponification and epoxidation to minimize biogenic interferences. Monitoring data reveal that virgin olive oils from the market can sometimes exceed the 2.0 mg/kg limit for the MOAH. Ten times higher levels are usually found in olive pomace oils (OPOs). In OPO, solvent extraction causes a significant reconcentration of hydrocarbons remaining on the solid matter after physical extraction and accumulating during the open-air storage of pomace. Conversely, for virgin oils, contamination can occur at multiple points along the supply chain, but harvesting emerged as the most important critical step, often due to accidental contact with lubricants, greases, or hydraulic fluids. Post-milling operations may also contribute to contamination. Mitigation strategies rely on Good Agricultural and Manufacturing Practices, focusing on the systematic replacement of technical-grade lubricants with food-grade alternatives. Additionally, olive washing can reduce initial MOSH content, while refining further lowers levels, particularly in lighter fractions. Full article

Extra-virgin olive oil (EVOO) is a chemically complex lipid matrix whose minor constituents—especially phenolic secoiridoids—drive sensory quality, oxidative stability, and health benefits. However, these bioactives are vulnerable to heat, light, oxygen, and pro-oxidant metals during processing and distribution, while the high cost of EVOO often makes it a target for adulteration and mislabeling. This review critically assesses nano-enabled, food-grade strategies that (i) preserve phenolics and aroma compounds through nanoencapsulation, inclusion complexes, Pickering stabilization, and structured lipid systems; (ii) control their release and bioaccessibility during digestion; and (iii) enhance authenticity verification via sensor-ready packaging, spectroscopy/chemometrics, and digital traceability systems (IoT, machine learning, blockchain). We align these innovations with the “product identity constraints” of the EVOO category and with official quality standards used in routine control (IOC/EU). Finally, we explore circular valorization of olive-mill by-products within food-centered biorefineries, outlining pathways to convert biomass into ingredients, materials, and energy, thus reducing environmental impacts. Research priorities are proposed to develop scalable, regulation-compliant nanotechnologies that extend shelf life and increase consumer trust without compromising EVOO category standards. Full article

Background and Objectives: During the past 25 years, a significant body of research has been conducted reporting on the salutary effects of the Mediterranean diet and extra-virgin olive oil, one of its main components. The initial studies were epidemiological observations on populations with very low mortality rates due to significant reductions in myocardial infarction fatalities. Population-based studies demonstrated that the Mediterranean diet with olive oil consumption is associated with a lower prevalence of cardiovascular and cerebrovascular disease, obesity, arthritis, and cancer. Materials and Methods: In this narrative review, we present recent studies on the effects of extra-virgin olive oil and the Mediterranean diet—compared with various other diets—on several vascular risk factors, including hypertension, hyperlipidemia, type 2 diabetes mellitus, and obesity, as well as their impact on cognitive decline and dementia. Results: This diet has been shown to improve cognitive function in patients with mild cognitive impairment, Alzheimer’s disease, vascular cognitive impairment, and vascular dementia. The main mechanisms responsible for cognitive improvement include control of arterial hypertension by reducing systolic and diastolic blood pressure, lowering triglycerides and low-density lipoprotein cholesterol and increasing high-density lipoprotein cholesterol, along with improvement in fasting glucose, insulin levels, and hemoglobin A1c in subjects with type 2 diabetes mellitus, as well as lowering body mass index and obesity. Conclusions: The Mediterranean diet and olive oil induce—along with prevention of cardiovascular disease and stroke—a significant improvement of vascular risk factors, slowing the progression of both vascular dementia and Alzheimer’s disease. There is a need for additional placebo-controlled clinical trials to confirm the supportive nutritional role of extra-virgin olive oil in age-associated cognitive decline in the elderly. Full article

Background: The Mediterranean diet (MD) represents a nutritionally balanced eating pattern characterized by high consumption of fruits, vegetables, legumes, nuts, whole grains, olive oil, fish, and extra-virgin olive oil as the principal fat source and limited intake of red meat and refined sugars. Emerging evidence indicates that the MD’s anti-inflammatory and antioxidant properties extend beyond systemic health, potentially reducing the risk and severity of periodontitis. This narrative review aimed to synthesize current evidence on the relationship between adherence to the MD and periodontal health outcomes. Methods: A comprehensive electronic literature search was conducted in PubMed without restrictions on publication date. Fourteen studies, ranging from 2019 to 2025, were included, encompassing human, clinical, experimental, and review designs that examined MD adherence and its effects on periodontal parameters. Eligible studies included cross-sectional, cohort, randomized controlled trials; systematic reviews; and animal models assessing clinical periodontal indices, inflammatory biomarkers, or microbial composition. Extracted data included study design, population characteristics, dietary assessment methods, and primary periodontal findings. Results: Most studies demonstrated that greater adherence to the MD was associated with improved periodontal parameters, including reduced probing pocket depth, clinical attachment loss, and bleeding on probing. Interventional trials showed significant reductions in systemic inflammatory markers such as IL-1β, TNF-α, and CRP, along with decreased counts of periodontopathogenic bacteria. Experimental studies further revealed the protective role of oleic acid and polyphenols in regulating macrophage activity, suppressing osteoclastogenesis, and enhancing IL-10 expression via epigenetic modulation. However, heterogeneity in dietary scoring systems, sample characteristics, and follow-up duration limited direct comparison, and not all associations reached statistical significance. Conclusions: Current evidence supports a beneficial association between MD adherence and periodontal health, mediated through anti-inflammatory, antioxidant, and microbiome-stabilizing mechanisms. Further standardized longitudinal and interventional studies are needed to confirm causality and refine nutritional strategies for periodontal disease prevention and management. Full article

Extra virgin olive oil (EVOO) is a key component of the Mediterranean diet, valued for its bioactive constituents and associated health benefits. This study evaluated the influence of four agronomic and processing factors—harvest month, destoning, fruit washing, and bottling delay—on the chemical composition of Kolovi EVOOs from the PGI Lesvos region. A total of 34 oils were produced under standardized conditions and analyzed for phenolic compounds, tocopherols, pigments, and squalene using UPLC-QTOF-MS and HPLC-DAD. The oils were characterized by consistently high nutritional quality, with most samples fulfilling EFSA health claim thresholds for hydroxytyrosol, tyrosol and its derivatives, and α-tocopherol. Harvest month was the most influential parameter: early harvested oils (October) contained significantly higher levels of phenolics, α-tocopherol, and lutein, whereas later harvests (November) were richer in squalene. Destoning produced modest changes, with slightly higher phenolics in non-destoned oils and reduced lipophilic antioxidants in destoned samples. Fruit washing selectively decreased hydrophilic phenolics, while lipophilic compounds were largely unaffected. Bottling delays of up to 48 h under protective conditions had negligible effects on composition, aside from minor increases in specific phenolic derivatives. These findings suggest that early harvesting and careful consideration of destoning are the most effective strategies for supporting the antioxidant profile of Kolovi EVOOs, while other practices can be adjusted with limited impact on quality. Full article

Background/Objectives: Gestational diabetes mellitus (GDM) is a prevalent metabolic disease associated with maternal and neonatal complications. Diets enriched with extra virgin olive oil may benefit metabolism and provide antioxidant effects. We aimed to evaluate the effects of dietary supplementation with extra virgin olive oil on metabolic parameters and insulinization rate in women with GDM. Methods: This is a multicenter, parallel, randomized controlled trial in which 190 patients with GDM were enrolled before week 29 of gestation and randomized into the Control group and the Intervention group. Patients in the Intervention group received the indication to consume three tablespoons of extra virgin olive oil (EVOO) daily. At term, metabolic parameters, insulin requirement and maternal and neonatal outcomes were evaluated. Results: Control and Intervention groups showed no differences in maternal age (31.7 ± 6.0 and 32.4 ± 5.2 years, respectively) or gestational age (26.5 ± 3.6 and 26.7 ± 3.3 weeks, respectively) at enrollment. Primary outcomes showed that EVOO consumption was associated with a reduction in insulin requirement (RR 0.595, 95% CI 0.361–0.967, p < 0.05). There was a significant reduction in triglyceridemia in the EVOO-supplemented group compared to controls (MD −43.3 mg/dL, 95% CI −66.8–−19.8, p < 0.01). There were no effects of the intervention on gestational weight gain. As secondary outcomes, maternal BMI and gestational age at delivery showed no changes between the groups. Although maternal and neonatal composite outcomes were not significantly reduced, the rate of neonates with more than one complication (RR 0.340, 95% CI 0.133–0.870, p < 0.05) and NICU requirement (RR 0.367, 95% CI 0.140–0.939, p < 0.05) were significantly reduced in the Intervention group. Conclusions: In GDM, maternal dietary supplementation with extra virgin olive oil resulted in reduction in maternal triglyceridemia, need of insulinization and neonatal complications. Full article

This study investigated the sensory and chemical properties of extra virgin olive oil (EVOO) under simulated domestic consumption conditions. EVOO with different polyphenol contents was analyzed and stored in the dark and at room temperature (20 °C) to simulate typical household storage and consumption. The volume of the bottles at the beginning was 1 L, from which 20 mL was taken daily from the same bottle for a period of one month. Chemical and sensory analyses were performed at the beginning and at the end of the experiment, whereas total polyphenol content and volatile organic compounds (VOCs) were analyzed at 7-day intervals. The results revealed a progressive reduction in total phenolic compounds, with a more pronounced decline in the sample initially characterized by a lower phenolic content. GC/MS analysis showed an increase in aldehydes such as trans, trans-2,4-octadienal, hexanal and nonanal, as well as in acetic acid and 1-octen-3-ol during a one-month period. These chemical changes were accompanied by a slight attenuation in the herbaceous sensory descriptors of EVOOs by the end of the simulated household consumption period. This suggests that choosing EVOOs with a higher phenolic content, in addition to their recognized nutritional benefits, can offer greater protection by slowing oxidative reactions and better preserving the quality of the oil during domestic use. Full article