Olive Oil Research Articles

Does Yogurt Enriched with Platelet-Activating Factor Inhibitors from Olive Oil By-Products Affect Gut Microbiota and Faecal Metabolites in Healthy Overweight Subjects? (A randomized, parallel, three arm trial.).

The effect of the daily consumption of a low-fat yogurt (150 g) enriched with Platelet-Activating Factor receptor (PAF-R) antagonists, or the plain one, on gut microbiota and faecal metabolites was investigated in healthy overweight subjects. A randomized, three-arm, double-blind, placebo-controlled, parallel-group study was performed that lasted 8 weeks. Blood and stools were collected and analyzed before and after the intervention. Our findings revealed that the intake of the enriched yogurt resulted in a significant increase in the levels of Bifidobacterium spp., Clostridium perfringens group and Firmicutes-to-Bacteroidetes (F/B) ratio. On the other hand, a significant increase in the levels of Lactobacillus and C. perfringens group was detected after the intake of the plain yogurt. The increase in the levels of C. perfringens group was inversely associated with the plasma catabolic enzyme of PAF, namely LpPLA2 (lipoprotein-associated phospholipase A2), a cardiovascular risk marker that has been linked with inflammation and atherosclerosis. Moreover, in the enriched with PAF-R antagonists yogurt group, the increased levels of C. perfringens group were also associated with lower PAF action assessed as ex vivo human platelet-rich plasma (PRP) aggregation. Additionally, a higher % increase in molar ratio of Branched Short Chain Fatty Acids (BSCFAs) was detected for both yogurt groups after the 8 week-intervention compared to control. The consumption of the enriched yogurt also resulted in a significant drop in faecal caproic levels and a trend for lower ratio of butyrate to total volatile fatty acids (VFAs) compared to baseline levels. Yogurt consumption seems to favorably affect gut microbiota while its enrichment with PAF-R antagonists from olive oil by-products, may provide further benefits in healthy overweight subjects. ClinicalTrials.gov (NCT02259205).

Biomonitoring polycyclic aromatic hydrocarbon levels in domestic kitchens using commonly grown culinary herbs

AbstractCooking is a significant source of polycyclic aromatic hydrocarbon (PAHs) emissions in indoor environments. A one-month biomonitoring study was carried out in previously selected rural Hungarian kitchens to evaluate cooking-related PAHs concentrations in 4 common kitchen vegetables such as basil, parsley, rocket and chives. The study had two mainobjectives: firstly, to follow PAHs accumulation pattern and to find out if this pattern can be associated with different cooking habits. Also, the usefulness of culinary herbs for indoor bioaccumulation studies was assessed. The 2-ring naphthalene was the dominant PAH in the majority of the samples, its concentrations were in the range of 25.4 µg/kg and 274 µg/kg, of 3-ring PAHs the prevalency of phenanthrene was observed, with highest concentration of 62 µg/kg. PAHs accumulation pattern in tested plants clearly indicated differences in cooking methods and cooking oils used in the selected households. Use of lard and animal fats in general resulted in the high concentrations of higher molecular weight (5- and 6-ring) PAHs, while olive oil usage could be associated with the emission of 2- and 3-ring PAHs. Culinary herbs, however, accumulated carcinogenic PAHs such as benzo[a]anthracene (highest concentration 11.9 µg/kg), benzo[b]fluoranthene (highest concentration 13.8 µg/kg) and chrysene (highest concentration 20.1 µg/kg) which might question their safe use.

Phenolic enrichment of foods curated in olive oil: Kinetics and chemical evaluation

Since ancient times food has been preserved in vegetable oils for curation. Nevertheless, the transfer of bioactive compounds from these oils to curated foods has not been studied. This research has evaluated the phenolic enrichment of foods curated in olive oil. For this purpose, six foods (fish, vegetables, and cheese) were immersed in olive oil for 30 days and analyzed to determine these antioxidant phenols by LC–MS/MS. Oleuropein aglycone, hydroxytyrosol and tyrosol were the main phenols quantitatively enriched in the foods (up to 42.1, 26.2 and 53.0 mg/kg, respectively). The total phenolic content ranged from 5.8 to 12.1 mg in the evaluated foods taking as reference the recommended daily intake (150 g for fish, 200 g for vegetables, and 50 g for cheese). This research proves the phenolic enrichment of foods curated in olive oil, which can hypothetically increase their antioxidant and bioactive properties.

Optimization of operating conditions for lampante olive oil deacidification by short path molecular distillation: Waste valorization approach

Short path molecular distillation (SPMD) is an advanced distillation eco-friendly technique performed under high vacuum with vast applications in food processing, including vegetable oils physical refining. In this research, lampante olive oil, as a low-grade byproduct of olive oil producing companies, with high free fatty acids (FFA) content of 10.11 (wt % as oleic acid) was deacidified using SPMD. Optimization of SPMD was carried out using Box-Behnken response surface methodology (RSM-BB). Three important operating factors including evaporation temperature (150–200 °C), feed flow rate (0.50–3.00 mL/min), and feed temperature (50–100 °C) were selected to evaluate the SPMD process. At the best separation conditions of 195 °C, 0.5 mL/min, and 50 °C, the FFA content, deacidification efficiency (DE) and polar compounds (PC) were determined as 1.42 wt %, 85.95 % and 8.2 wt % respectively. Furthermore, SPMD efficiency was compared to some conventional methods including fractional distillation (FD), steam stripping distillation (SSD) and alkali neutralization (AN). In addition, the impact of FFA content on SPMD process was examined. It was concluded that SPMD could effectively and sustainably deacidify lampante olive oil to a reasonable extent and could facilitate the physical refining as a valorization process.

Stability of monovarietal Sicilian olive oils under different storage condition: Chemical composition, sensory characteristics, and consumer preference

Monovarietal olive oils, known for their distinct aromatic profiles, face challenges in preserving their initial quality due to variations in stability and susceptibility to oxidative deterioration. This study focused on the storage stability of two Italian cultivars, ‘Biancolilla’ and ‘Cerasuola’, from Sicily, chosen for their aromatic complexity and divergent storage stability. Oils, whether filtered or unfiltered, underwent storage at two thermal regimes (18 °C and – 20 °C) over a year. The combination of filtration and low-temperature storage was employed to mitigate oxidative deterioration and hydrolytic processes, as filtration removes suspended particles and emulsified water, while low temperatures slow down enzymatic activities and oxidative reactions, thereby enhancing the overall stability and shelf life of the olive oils. Unfiltered samples at room temperature showed a significant increase in secoiridoid aglycone derivatives (Hydroxytyrosol and Tyrosol) due to hydrolytic processes, along with a decrease in secoiridoid aglycone. Filtration delayed these processes, with a more pronounced effect observed when combined with −20 °C storage. Sensory analysis identified the emergence of the “fusty” defect in the less resilient ‘Biancolilla’ cultivar after six months, a phenomenon mitigated by filtration and freezing. Consumer tests validated these findings. In summary, the synergistic approach of combining filtration with low-temperature storage emerges as a promising strategy for maintaining high-quality standards, especially for less stable monovarietal extra virgin olive oils. This strategy ensures compliance with EU regulations beyond the conventional 12-month shelf life, offering a practical solution for preserving the nutritional and sensory quality of olive oil.

Biological Activities of Virgin Coconut and Virgin Olive Oil Mixture against Oral Primary Colonizers: An In Vitro Study.

This study aimed to explore the potential synergistic interaction of virgin coconut oil (VCO) and virgin olive oil (VOO) mixture against Streptococcus sanguinis, Streptococcus mutans, and Lactobacillus casei in a single and mixture species through the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), antiadherence, and antibiofilm activities. The broth microdilution technique was used to individually determine the MIC of both oils and an oil mixture (in the ratio of 1:1) in a 96-well microtiter plate. As for the MBC, the subcultured method was used. The fractional inhibitory concentration index (ΣFIC) was determined to identify the interaction types between both oils. The oil mixture at its MIC was then tested on its antibiofilm and antiadherence effect. The MIC of the oil mixture against the tested microbiota was 50-100%. The oil mixture was bactericidal at 100% concentration for all the mentioned microbes except S. mutans. The ΣFIC value was 2 to 4, indicating that the VCO and VOO acted additively against the microbiota. Meanwhile, the oil mixture at MIC (50% for S. sanguinis and L. casei; 100% for S. mutans and mixture species) exhibited antiadherence and antibiofilm activity toward the microbiota in mixture species. The oil mixture possesses antibacterial, antibiofilm, and antiadherence properties toward the tested microbiota, mainly at 50-100% concentration of oil mixture. There was no synergistic interaction found between VCO and VOO. Children and individuals with special care may benefit from using the oil mixture, primarily to regulate the biofilm formation and colonization of the bacteria. Furthermore, the oil mixture is natural and nontoxic compared to chemical-based oral healthcare products. How to cite this article: Ng YM, Sockalingam SNMP, Shafiei Z, et al. Biological Activities of Virgin Coconut and Virgin Olive Oil Mixture against Oral Primary Colonizers: An In Vitro Study. J Contemp Dent Pract 2024;25(3):260-266.

Ultrasonic-Assisted Preparation of Biodiesel Products from Vegetable Oils.

Utilizing vegetable oil as a sustainable feedstock, this study presents an innovative approach to ultrasonic-assisted transesterification for biodiesel synthesis. This alkaline-catalyzed procedure harnesses ultrasound as a potent energy input, facilitating the rapid conversion of extra virgin olive oil into biodiesel. In this demonstration, the reaction is run in an ultrasonic bath under ambient conditions for 15 min, requiring a 1:6 molar ratio of extra virgin olive oil to methanol and a minimum amount of KOH as the catalyst. The physiochemical properties of biodiesel are also reported. Emphasizing the remarkable advantages of ultrasonic-assisted transesterification, this method demonstrates notable reductions in reaction and separation times, achieving near-perfect purity (~100%), high yields, and negligible waste generation. Importantly, these benefits are achieved within a framework that prioritizes safety and environmental sustainability. These compelling findings underscore the effectiveness of this approach in converting vegetable oil into biodiesel, positioning it as a viable option for both research and practical applications.

Alleviation of Lead Nitrate-Induced Nephrotoxicity by Garlic Essential Oil in Albino Mice: A Comprehensive Study on Inflammation and Genotoxicity

Lead (Pb) is a hazardous environmental contaminant that has been linked to renal impairments when consumed. As a part of this study, we explored garlic essential oil’s potential therapeutic uses against Lead nitrate (PbNo3)2-mediated nephrotoxicity. Six experimental groups of six mice each were employed and groupings were further formed as - Control, (PbNo3)2, (PbNo3)2 + low dosage of garlic essential oil, (PbNo3)2 + high dosage of garlic essential oil, (PbNo3)2 + Silymarin and (PbNo3)2 + olive oil groups. (PbNo3)2 treatment enhanced the progression of renal inflammation by activating the NFĸB signaling pathway which in turn increased the levels of pro-inflammatory mediators like TNF-α, IFN-γ and IL-6. With that, the reduction of IL-10 cytokine level was also noticed. Interestingly, oral administration of garlic essential oil to some extent improved biological functioning since it was able to substantially decreased the inflammatory processes in the renal tissue. The Lead nitrate intoxicated group also showed substantially higher parameters of the comet assay, including the percentage of DNA in the tail, tail length and the moment of the tail, demonstrating the degree of genetic instability caused by heavy metal exposure. However, garlic essential oil to some extent was able to recover these parameters and ensure molecular repair.

Influence of the Degree of Fruitiness on the Quality Assessment of Virgin Olive Oils Using Electronic Nose Technology.

The electronic nose is a non-invasive technology suitable for the analysis of edible oils. One of the practical applications in the olive oil industry is the classification of virgin oils based on their sensory characteristics. Notwithstanding that this technology, at this stage, cannot realistically replace the currently used methods, it is fruitful for a preliminary analysis of the oil quality. This work makes use of this technology to develop a methodology for the detection of the threshold by which an extra-virgin olive oil (EVOO) drops into the virgin olive oil (VOO) category. With this aim, two features were studied: the level of fruitiness level and the type of defect. The results showed a greater influence of the level of fruitiness than the type of defect in the determination of the detection threshold. Furthermore, three of the sensors (S2, S7 and S9) of the commercial e-nose PEN3 were identified as the most discriminating in the classification between EVOO and VOO oils.

Peculiarities of nutrition of patients with metabolic syndrome in the aspect of treatment and prevention

The hallmark of metabolic syndrome (MS) is the associated risks of cardiovascular disease and type 2 diabetes, as well as other harmful conditions such as non-alcoholic fatty liver disease, etc. In this article, we would like to highlight the available scientific evidence on the relationship between lifestyle changes and MS and its components in order to obtain recommendations for the prevention and treatment of MS. Body weight (BW) reduction through calorie-restricted diets, along with increased energy expenditure through physical activity, has been shown to aid in the prevention and treatment of MS. A Mediterranean diet with or without calorie restriction is an effective component of treatment. Due to the increased consumption of unsaturated fats, primarily from olive oil, and to emphasize the consumption of legumes, cereals (whole grains), fruits, vegetables, nuts, fish and low- fat dairy products, as well as moderate alcohol consumption. Other dietary patterns (DASH, Scandinavian and vegetarian diets) have also been suggested as alternatives for the treatment and prevention of MS. A mandatory condition is to stop smoking and reduce the consumption of sweetened beverages. These approaches are not effective in all patients, and more research is needed to determine the most appropriate therapy for MS. In summary, a healthy lifestyle is critical for preventing or delaying the onset of MS in susceptible individuals and preventing cardiovascular disease and type 2 diabetes in those who already have MS. The recommendations provided in this article should help patients and physicians understand and implement the most effective lifestyle modification approaches to prevent metabolic syndrome and improve cardiometabolic status.

Combination of Natural Deep Eutectic Solvents and Nano-Liquid Chromatography towards White Analytical Chemistry: A Practical Application

In this work, a green and practical analytical method based on natural deep eutectic solvents (NADES) as extraction agents and nano-liquid chromatography as a separation technique was developed. To demonstrate the applicability of the methodology, alkylphenols and bisphenol A were evaluated as model compounds in olive and sunflower oils as model fatty samples by liquid–liquid microextraction. With this aim, several NADES based on mixtures of choline chloride with glycerol, lactic, ascorbic, and citric acids or glycerol with amino acids were evaluated as potential extraction solvents. In addition, to select the most suitable stationary phase for the separation of this group of contaminants, some stationary phases were tested, including Pinnacle II phenyl, Cogent Bidentate C18™, and XBridge® C18. The last one provided the best performance with an analysis time of 11 min. To solve the problem of the compatibility of hydrophilic NADES with chromatographic systems without harming the solubility of analytes, different aqueous organic mixtures were tested. Methanol/water mixtures were the most suitable as an injection solvent. Finally, following the White Analytical Chemistry principles, different tools were used to evaluate the greenness, the practicality, and applicability of the method based on the Analytical Eco-Scale, the Analytical GREEnness metric approach, and the Blue Applicability Grade Index.

Enhancing olive oil quality through an advanced enrichment process utilizing ripe and fallen fruits

Enhancing olive oil quality through an advanced enrichment process utilizing ripe and fallen fruits

Phenotypic and genetic characterization of a lipolytic Ralstonia mannitolilytica isolate from petroleum-contaminated soil in Iraq.

Lipases play a crucial role in various industrial applications, and microbial lipases, particularly those from bacteria, possess significant properties. With increasing concerns about the environmental and health impacts of hydrocarbons from pipelines and refineries, there is a growing need to mitigate the risks associated with these compounds. In this study, 40 bacterial isolates were recovered from contaminated soil samples collected from multiple refineries across Iraq. Using the Vitek system, bacterial isolates were identified up to the species level, revealing that only 12 isolates exhibited lipase-producing capabilities. Among the lipase-producing isolates, Ralstonia mannitolilytica demonstrated the highest extracellular lipase activity, as determined by an olive oil plate assay supplemented with rhodamine B. Confirmation of the species identity was achieved through 16S rRNA gene sequencing, with the obtained sequence deposited under accession number LC772176.1. Further sequence analysis revealed single nucleotide polymorphisms (SNPs) in the genome of Ralstonia mannitolilytica strain H230303-10_N19_7x_R2 (CP011257.1, positions 1,311,102 and 1,311,457). Additionally, the presence of the lipase gene was confirmed through amplification and sequencing using a thermocycler PCR. Sequence analysis of the gene, aligned using Geneious Prime software, identified SNPs (CP010799, CP049132, AY364601, CP011257, and CP023537), and a phylogenetic tree was constructed based on genetic characterization. Our findings highlight the potential of Ralstonia mannitolilytica as a promising candidate for lipase production and contribute to our understanding of its genetic diversity and biotechnological applications in hydrocarbon degradation and industrial processes.

Olive stone as a filler for recycled high-density polyethylene: A promising valorization of solid wastes from olive oil industry

The valorization of solid residues generated from olive oil production is a challenging issue for olive oil-producing countries such as Greece, Italy, Spain, etc. Olive stone waste is a type of lignocellulosic biomass with potential use as a natural additive in polymeric composites. In the present study, olive stone waste was compounded with recycled high-density polyethylene (rHDPE) via melt mixing in 5 %, 10 %, and 20 % wt. Additionally, the effect of Joncryl (JC) and polyethylene-grafted maleic anhydride (PE-g-MA) as compatibilizers on the properties of the green composites was also investigated. It is worth mentioning that JC was employed for the first time as a compatibilizer for polyolefin composites with olive stone. The materials underwent structural, thermal, and mechanical characterization using multiple complementary techniques. Scanning electron microscopy showed good dispersion of the filler for all composites, while in the compatibilized samples a markedly better adhesion was observed. Tensile tests revealed an increase in the elastic modulus for the composite with 10 % wt. olive stone. Furthermore, all materials demonstrated a strong antioxidant activity, rendering them interesting for active packaging applications. Overall, the solid residue from olive processing can enhance the properties of rHDPE, paving the way to promote circular economy.

Exploring Ultrasonic Velocity and Compressibility Analysis for Various Edible Oils: A Comparative Study

This study presents a comparative analysis of ultrasonic velocity and compressibility properties in a selection of commonly used edible oils, namely mustard oil, olive oil, coconut oil, groundnut oil, and soybean oil. Understanding the acoustic and compressibility characteristics of these oils is of significant interest due to their widespread culinary and industrial applications. Ultrasonic velocity measurements were conducted using a precision ultrasonic velocity analyzer, while compressibility analysis was performed through precise density measurements. Our findings reveal distinct differences in ultrasonic velocity and compressibility among the various oils. This comparative study contributes to our understanding of the acoustical and compressibility characteristics of edible oils, offering potential applications in food processing, quality control, and product development. Additionally, the findings may have implications in the field of biomedical and industrial applications where these oils are utilized.

The effect of hydrosol types on phytochemical properties, phenolic compounds, fatty acid profiles and sensory properties of ‘Ayvalık’ olive fruits fermented in few spice hydrosols

SummaryIn this study, the changes in oil content, bioactive components, radical scavenging activity, phenolic profiles, fatty acid components and sensory characteristics of ‘Ayvalık’ olive fruits fermented in brine thyme, sage and rosemary hydrosols were investigated. Total carotenoid and total phenolic results of olives were recorded between 0.02 (thyme hydrosol) and 0.24 μg g−1 (control (only brine 10%)) to 213.92 (rosemary hydrosol) and 432.54 mg GAE per 100 g (fresh ‘Ayvalık’ olive), respectively. Total flavonoids of olive fruits fermented in different hydrosols were reported between 755.87 mg per 100 g (rosemary hydrosol) and 1404.76 mg per 100 g (fresh ‘Ayvalık’ olive). Radical scavenging capacity of fermented ‘Ayvalık’ olive fruits was reported between 10.20 (control) and 10.55 mmol kg−1 (rosemary hydrosol). Verbascoside results of fresh and fermented ‘Ayvalık’ olive fruits in brine and hydrosols were identified between 107.00 mg per 100 g (sage hydrosol) and 167.20 mg per 100 g (fresh ‘Ayvalık’ olive). Oleic and linoleic acid values of olive oils changed to be between 67.07% (rosemary hydrosol) and 68.71% (control) to 10.89% (control) and 11.86% (rosemary hydrosol), respectively. Overall, ‘Ayvalık’ olive fruit fermented in brine was most appreciated by the panellists, followed in descending order by olives fermented in thyme, sage, and rosemary hydrosols.

Mechanical properties, sustained release, and oxygen scavenging properties of nanocomposite films loaded with bimetallic nanoparticles (Fe2O3/TiO2) in extra virgin olive oil.

The aim of this study was the synthesis of bimetallic nanoparticles based on Fe2O3/TiO2 and its use in the poly(lactic acid) (PLA) films as an oxygen scavenger in extra virgin olive oil (EVOO) packaging. Bimetallic nanocomposites were prepared by two different precipitation methods (precipitation with ammonia and sodium hydroxide). The characteristics of bimetallic nanoparticles precipitated with sodium hydroxide (Na-Ti0.01Fe0.048O0.08) and bimetallic nanoparticles precipitated with ammonia (NH-Ti0.01Fe0.022O0.09) were compared. Relative amounts of elements in bimetallic nanocomposites and their morphological characteristics were determined using field emission scanning electron microscopy coupled with energy-dispersive X-ray spectrometer. Porosity volume and surface area of bimetallic nanoparticles were calculated using adsorption-desorption isotherms and the Brunauer-Emmett-Teller method. The formation/characterization of bimetallic nanoparticles and their location in the matrix of PLA-based nanocomposite film was studied using X-ray diffraction and Fourier transform infrared. In nanocomposite films based on PLA, bimetallic nanoparticles lead to better oxidative stability (peroxide value, p-anisidine index, K232, and K270) of the EVOO and oxygen scavenging during storage compared to free nanoparticles. Mechanical properties of nanocomposite films were improved due to bimetallic nanoparticles, which were better for Na-Ti0.01Fe0.048O0.08. In vitro release modeling of the bimetallic nanoparticles in EVOO proved that Fickian diffusion is the dominant mechanism, and the Peleg model was the best description of the release behavior of nanoparticles.

The frequency of selective functional foods consumption is related to improved anthropometric obesity indices: A cross-sectional study in Greek and Cyprian adults

Background: Obesity remains a public health problem. Recent, novel strategies suggest thefrequent inclusion of functional foods for better management of adiposity markers and obesityprevention. Numerous epidemiological and clinical studies demonstrate specific naturalfunctional foods of the Mediterranean Diet and innovative processed foods, enhanced withbioactive compounds, that they may present a possible beneficial role on this approach. Methods: In this cross-sectional epidemiological study, 319 Greeks and Cyprians, aged 18-75years were voluntary recruited in personal interviews. A validated Functional Food Frequency ofConsumption (FFFQ) was filled out, recording the frequency of selective functional foodsconsumption, following by anthropometric and body composition evaluations. Data collectionand statistical analysis were conducted, to assess the possible association of functional foodsfrequency of consumption with adiposity markers. Results: Olive oil is a main part of the daily diet of the representative sample of Greek andCyprian population and its frequency of intake was inversely related to body weight, taking intoaccount the lifestyle pattern and social parameters. Considering general habits andsociodemographic characteristics, Body Mass Index (BMI) was directly associated with thefrequency of consumption of split peas, turmeric, cinnamon, honey, whole wheat- and gluten-free pasta, as well as of gluten-free and enhanced bakeries. These functional food groups areconsumed by majority in a monthly basis, except of honey which is weekly consumed by themajority of the study population. Conclusion: The results suggest that the daily intake of olive oil, as the main characteristic ofMediterranean Diet, may be effective on body weight management. The frequency rise ofspecific spices, honey, functional pasta and bakeries consumption, may lead to increases inmarkers of adiposity. Further research is needed to safely conclude to these claims and theimplementation of nutritional treatment programs with functional foods may prove effective inthe prevention and management of obesity. Keywords: epidemiological study; functional foods; frequency of consumption; obesity;adiposity association; Greeks; Cyprians

Fourier transform infrared spectroscopy coupled with chemometrics for the monitoring of virgin olive oil quality during storage up to 18 months

Fourier transform infrared spectroscopy coupled with chemometrics for the monitoring of virgin olive oil quality during storage up to 18 months

Teaching fluorescence of plants & algae in physics class to address climate change

In physics classes and general education classes, teaching the concept of fluorescence can be challenging, and it may seem too theoretical for some students. A short YouTube video titled ‘Seeing Photosynthesis from Space’ displays a global map of photosynthesis, and this is an excellent, attention-getting way to visually introduce fluorescence to students and also to address climate change. Therefore, three hands-on activities were designed using spinach chlorophyll ethanol extract and olive oil to observe the fluorescence emission; in addition, a smartphone spectrophotometer was employed to observe the spectrum of the emission. The class also addressed the issue of global warming because the absorption of CO2 by plants and algae is decreasing, which may cause serious climate change.