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The increasing interest in endocannabinoid-like compounds (ECL) in food stems from their important physiological roles, including energy metabolism and satiety. In this study, the effect of fermentation or alkalisation on the formation of ECL compounds in table olives was investigated. N -acylethanolamines, monoacylglycerols, N -acylamino acids, and N -acylneurotransmitters were monitored. Results revealed that alkaline treatment led to a significant increase in the concentrations of N -oleoylethanolamide (80%), N -palmitoylethanolamide (93%), N -linoleoylethanolamide (51%), and 1-oleoylglycerol (679%) compared to control. While N -oleoylethanolamide, N -palmitoylethanolamide, N -linoleoylethanolamide, 1- and 2-oleoylglycerol, 1- and 2-linoleoylglycerol, and oleoylphenylalanine were initially absent or present in trace amounts, their levels significantly rose during fermentation. The formation rate of these compounds was higher in olives fermented in water than those in brine. The study provides detailed information on how specific ECL compounds respond to different processing methods, offering valuable information for optimising table olive production to enhance its nutritional benefits. [Display omitted] • Biologically active oleoylphenylalanine forms during olive fermentation. • N -acylethanolamine levels increase during both olive fermentation and alkalization. • N -Acylethanolamines and monoacylglycerols show higher increases in NaCl absence. [ABSTRACT FROM AUTHOR]

Ultra-flexible nanoliposomes (UNL) coated with sodium cholate were fabricated using the thin film hydration technique to encapsulate oleocanthal (OLEO), oleacein (OLEA), oleuropein (OLEU), and hydroxytyrosol (HT) for improving their stability and bioactivity. Their physicochemical properties were further validated through DLS, FTIR, XRD, TGA, and DSC analyses. Negative-staining TEM imaging revealed well-dispersed UNL with laminar vesicles inside. Additionally, their transdermal studies in vitro demonstrated that UNL enhanced the cumulative release of OLEO, OLEA, OLEU, and HT by 3.13, 2.76, 2.59, and 2.83 times, respectively. Furthermore, their release mechanisms were better approximated the Peppas-Sahlin model rather than the Korsmeyer-Peppas and Higuchi models, which governed by Fickian diffusion. Moreover, comparing to their compounds, UNL structure exhibited improved their antioxidant and cytotoxicity properties, highlighting their potential as effective delivery agents in humans. These results offer a novel approach for stabilizing biologically active polyphenols from Olea europaea, paving the way for enhanced human health applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Anthracnose, the most critical disease affecting olive fruits, is caused by Colletotrichum species. While developing olive fruits are immune to the pathogen regardless of the cultivar, the resistance level varies once the fruit ripens. The defense mechanisms responsible for this difference in resistance are not well understood. To explore this, we analyzed the phenolic metabolic pathways occurring in olive fruits and their susceptibility to the pathogen during ripening in two resistant cultivars ('Empeltre' and 'Frantoio') and two susceptible cultivars ('Hojiblanca' and 'Picudo'). Overall, resistant cultivars induced the synthesis of aldehydic and demethylated forms of phenols, which highly inhibited fungal spore germination. In contrast, susceptible cultivars promoted the synthesis of hydroxytyrosol 4-O-glucoside during ripening, a compound with no antifungal effect. This study showed that the distinct phenolic profiles between resistant and susceptible cultivars play a key role in determining olive fruit resistance to Colletotrichum species. • Fruits at turning stage show varied pathogen resistance due to phenolic profile changes. • Susceptible cultivars' drupes convert secoiridoids to hydroxytyrosol-4-O-glucoside, reducing anthracnose tolerance. • Oleuropein, ligstroside, and their derivatives are key in inhibiting spore germination. • Resistant cultivars maintain high fungicidal phenolic compounds (>90% of total phenols) during ripening. [ABSTRACT FROM AUTHOR]

An antioxidant food packaging material was developed and applied to fresh minced pork meat. The material consists of a multilayer polyethylene film in which 4 different concentrations (2%, 5%, 10%, and 15%) of olive leaves (OL) extract were immobilized in an adhesive formula used to build the multilayer. The antioxidants were not in direct contact with the meat. The packaged meat was kept at 4 °C during 16 days and finally analyzed by two methods: Raman spectroscopy and thiobarbituric acid reactive substances (TBARS). Raman demonstrated a higher sensitivity for antioxidant evaluation than TBARS. Color of fresh meat packaged with the active film was also measured to evaluate the shelf life of packaged meat. The results showed that active film containing natural antioxidants efficiently enhanced the stability of fresh meat against oxidation processes, thus being a promising way to extend the shelf life of fresh minced meat for about two days. [ABSTRACT FROM AUTHOR]

The olive species ( Olea europaea L.) is characterized by significant phenotypic and genetic variability the genetic matrix has a strong influence on several important extra virgin olive oil (EVOO) chemical components. Four clones from cultivars autochthonous of the Emilia Romagna region were selected for their notable performance in terms of agronomical characteristics, and the quality of the olive oil produced was studied in detail. In particular, we analyzed the fatty acid composition, the phenolic profile and the sensory analysis of the oils from these clones and compared them with the oils from the respective cultivars. Most of the new clones, all already provided with a genetic and sanitary certification, exhibited overall higher qualitative standards than the cultivars, producing monovarietal oils interesting both nutritionally and from a sensory point of view, and furthermore with a beneficial effect on health. [ABSTRACT FROM AUTHOR]

Olive oil is considered a premium product for its nutritional value and health benefits, and the ability to define its origin and varietal composition is a key step towards ensuring the traceability of the product. However, isolating the DNA from such a matrix is a difficult task. In this study, the quality and quantity of olive oil DNA, isolated using four different DNA isolation protocols, was evaluated using the qRT-PCR and ddPCR techniques. The results indicate that CTAB-based extraction methods were the best for unfiltered oil, while Nucleo Spin-based extraction protocols showed greater overall reproducibility. The use of both qRT-PCR and ddPCR led to the absolute quantification of the DNA copy number. The results clearly demonstrate the importance of the choice of DNA-isolation protocol, which should take into consideration the qualitative aspects of DNA and the evaluation of the amplified DNA copy number. [ABSTRACT FROM AUTHOR]

In this article, we report an effective procedure for the selective isolation of oleanolic acid 1 and maslinic acid 2 (3.4 and 8.5 mg/g DW, respectively) from pomace olive ( Olea europaea L.) using an ultrasonic bath, and the synthesis of a series of new triterpenic acid esters. The compounds were characterized by their spectral data and were evaluated for their antimicrobial activity. Among the compounds tested, those having sulfur and chlorine atoms were found to be antibacterial. They showed activity against two Gram-positive bacteria Staphylococcus aureus and Enterococcus faecalis and two Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa (MICs within a range of 5–25 μg/mL). The fungus Penicillium italicum was found to be the most sensitive to both sulfur derivatives: (3β)-3-((thiophene-2-carbonyl)oxy)-olean-12-en-28-oic acid ( 1a ) (IZ = 22 mm) and (2α,3β-2,3-bis((thiophene-2-carbonyl)oxy)olean-12-en-28-oic acid ( 2a ) (IZ = 24 mm). [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied fruit and oil composition and taste in organic and conventional olives. [•] Fruit characteristics were similar but organic oil had more polyphenols. [•] This resulted in more bitter oils, as revealed by the sensory analysis. [•] The concentration of several compounds in the fruit, differed among treatments. [•] Some effects might be difficult to observe without a broad-spectrum analysis. [Copyright &y& Elsevier]

Highlights: [•] Domestic olives had a fairly homogeneous composition of volatiles. [•] Imported olives had a much more diverse and complex mixture of volatiles. [•] Imported olives had fermentation-derived volatiles that were not present in domestic olives. [ABSTRACT FROM AUTHOR]

• Characterization of olive pomace from 43 cultivars in three consecutive agronomic seasons. • Evaluation of variability sources to explain the concentration of bioactive compounds. • Clusters of cultivars were identified according to the pomace composition. • Secoiridoids were especially relevant to explain the distribution of cultivars in clusters. • Clusters of cultivars followed a similar distribution to those found for olive oil. Olive mill wastes, generated in the extraction of virgin olive oil (VOO), are of important concern for the industry owing to the produced volume and polluting load, mainly associated with the presence of organic compounds. Among them, it is worth mentioning bioactive compounds, mainly phenols and triterpenes, which could be potentially isolated for further use in the cosmetic, pharmaceutical, or food industries. This research analyzed the olive pomace after extraction of VOO from fruits harvested of 43 international olive cultivars during three consecutive seasons. The cultivar was identified as the most determinant factor to explain the variability in the relative concentration of phenols and terpenic acids in the extracts. In addition, the characterization of olive pomace extracts allowed clustering cultivars according to the profile of bioactive compounds. Finally, we identified the components responsible for the observed discrimination that was explained according to biosynthetic metabolic pathways. [ABSTRACT FROM AUTHOR]

Abstract: Phenolic compounds from virgin olive oil are known to play an antioxidant role in preventing biomolecule damage. One of the most abundant components of olive oil is an oleuropein derivative named oleacein (dialdehydic form of decarboxymethyl elenolic acid linked to hydroxytyrosol; 3,4-DHPEA-EDA). The aim of the study was to establish the antioxidant activity of oleacein for an array of reactive oxygen (superoxide anion, ; hydrogen peroxide, H2O2; hypochlorous acid, HOCl) and nitrogen species (nitric oxide, NO; peroxynitrite, ONOO−) formation, using in vitro non-cellular systems, as well as cellular screening systems (human neutrophil oxidative burst, monocytes’ nitric oxide production). We used a well-known antioxidant, oleuropein, as a reference compound. Oleacein proved to be stronger in the reduction of formyl-met-leu-phenylalanine (f-MLP) and phorbol–myristate–acetate (PMA)-induced oxidative bursts in neutrophils (IC50 =1.8μM, IC50 =1.5μM, respectively) and myeloperoxidase release (IC50 =8.8μM) than was oleuropein (IC50 =2.4μM, IC50 =16.0μM, IC50 =30.7μM, respectively). Both compounds were stronger scavengers of than H2O2. Oleuropein did not scavenge HOCl as opposed to oleacein (IC50 =1.5μM). Both compounds, in a concentration range 1–10μM, significantly decreased nitrogen species formation in cell-free systems and by lipopolysaccharide (LPS)-stimulated monocytes. [Copyright &y& Elsevier]

Abstract: A distinctive methodology is developed to trace out the mixing into olive oil, which is marketed every year with 20% or more fraudulent oils. Such adulteration has been difficult to differentiate using fatty acid analysis and other available current techniques, as chemically fatty acids are same regardless of their source. The total genomic DNA isolated from olive oil, contaminated with canola and sunflower was analysed for single nucleotide polymorphism (SNP) variation in noncoding spacer region between psbA-trnH and partial coding region of matK of plastid genome. These DNA regions were amplified by PCR using specific primers and resulting DNA sequences were matched to the predetermined consensus DNA barcode sequences of canola and sunflower for discerning the contaminations in olive oil samples. The matching of an adulterant DNA sequence with their respective DNA barcode revealed the mixing of canola and sunflower oil into olive is simpler way and the combined approach of molecular biology and bioinformatics technology can be used as an inexpensive method for ensuring the purity of olive. This plastid based molecular DNA technology can be used for rapid detection of adulteration easily up to 5% in olive oil. [Copyright &y& Elsevier]

Abstract: A recent pharmacognostic survey on the European food market highlighted a previously unreported adulteration of Mediterranean oregano. Dried crushed leaves, silvery grey in colour but devoid of glandular hairs and with unequivocal xerophytic adaptations were copiously spotted (20–30% w/w) in a number of commercial samples. Microscopical investigations narrowed the range of suspect candidates to Olea europaea L. and a method based on Sequence-Characterised Amplified Regions markers (SCARs) was developed from Random Amplified Polymorphic DNA markers (RAPDs) specific for O. europaea, in order to authenticate the contaminant and set up a fast, sensitive, reliable and low-cost screening of dried commercial Mediterranean oregano samples. The method enabled the unequivocal detection of low amounts (up to 1%) of olive leaves in both artificial and commercial batches, allowing the preemptive rejection of suspect samples and reducing the number of samples to be subjected to more careful pharmacognostic analyses. The relatively short dimension of the amplicons is suitable for the analysis of potentially degraded DNA obtained from dried and processed commercial plant material and given their specificity the method may be enforceable also in case of forensic disputes even in case of finely ground material. [ABSTRACT FROM AUTHOR]

Abstract: The woody portion of olive tree pruning is a source of natural antioxidants of potential interest for the food industry. This work deals with the isolation and identification of further antioxidants present in an ethyl acetate extract of olive (Olea europaea L.) wood. Thus, a new secoiridoid, oleuropein-3″-methyl ether (1), together with six known secoiridoids, 7″S-hydroxyoleuropein (2), jaspolyanoside (3), ligustroside 3′-O-β-d-glucoside (4), jaspolyoside (5), isojaspolyoside A (6) and oleuropein 3′-O-β-d-glucoside (7) were isolated by combining HPLC with fast on-line post-column radical scavenging activity evaluation. The structures of these compounds were determined by spectroscopic methods. The antioxidant activity of the pure compounds was determined by measuring the radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH ). Compounds 2, 5 and 7 displayed a higher antioxidative effect than the synthetic antioxidant BHT and lower than rosmarinic acid, whereas compounds 3 and 4 showed weak DPPH scavenging activity. [ABSTRACT FROM AUTHOR]

Abstract: Olive trees (Olea europaea L. Cv. Cobrançosa) from the northeast of Portugal were sprayed with three different copper formulations [bordeaux mixture (copper sulphate+calcium hydroxide−20% Cu), copper hydroxide (40% Cu) and copper oxychloride (50% Cu)] to control olive fungal diseases. The residues of copper in olive leaves, harvested at different times, were evaluated by atomic absorption spectrometry. At all the collection times, treated olive leaves had significantly higher copper contents, compared to the control. The different copper amounts in pesticide formulations lowered the leaves contents in total phenols and hence their antioxidant properties. Olive leaves sprayed with copper oxychloride possessed the highest copper levels and the lowest content in phenols, which influenced its antioxidant activity (higher EC50 values for reducing power, scavenging effect on DPPH radicals and inhibition of erythrocyte hemolysis). Leaves without copper residues proved to be a good natural source of antioxidants, giving values comparable to the reference compounds. [Copyright &y& Elsevier]

Abstract: Olives (Olea europaea cv. Coratina) used for oil production were stored for 30 days at three different temperatures and under different atmospheres (ambient temperature, 5°C with a flux of humidified air, 5°C with a flux of 3%O2 +5%CO2). The olives were kept in jars used for fruit storage, each with a capacity for 1.5kg of olives. Conventional analyses (acidity, peroxide value, specific extinction coefficient at 232nm and 270nm) and non conventional (polar compounds) analyses were carried out in order to measure the hydrolytic and oxidative degradation of the oils obtained from the olives. Storage at 5°C, both under a flow of humidified air and a flow of 3%O2 +5%CO2, produced oils that maintained their initial chemical qualities until the end of the experimentation; whereas storage of olives at room temperature led to their deterioration after 15 days of storage. [Copyright &y& Elsevier]

Abstract: Fruits from the same variety of Olea europaea L., grown under different environmental conditions in the north of Tunisia, were harvested at the same ripening degree and immediately processed. The volatile profile of virgin olive oils was established using solid phase, micro-extraction (SPME) and gas chromatography-mass spectrometry (GC-MS). Compounds belonging mainly to the following chemical classes characterised the volatile profiles: esters, aldehydes, ketons, aliphatic alcohols and hydrocarbons. Significant differences in the proportions of volatile constituents from oils of different geographical origins were detected and the major volatile in approximately 50% of the oil samples was the aldehyde (E)-2-hexenal. The results suggest that, beside the genetic factor, environmental conditions influence the volatile formation. [Copyright &y& Elsevier]

Abstract: Two new phenolic compounds were isolated from fruits of Olea europaea, Hojiblanca cultivar. The first compound is the methyl acetal of the aglycone of ligstroside, while the second derivative, not yet reported in the literature, is the β-hydroxytyrosyl ester of methyl malate. These microcomponents may be responsible for hedonistic-sensorial characteristics of olive products. [Copyright &y& Elsevier]

• Study of VOO phenolic variability in worldwide olive cultivars over three crop seasons. • Phenolic profiles of monovarietal VOO samples from 44 cultivars evaluated by LC–MS/MS. • Secoiridoids were the most concentrated phenols in olive oil. • Genotype was the main factor explaining VOO phenolic content but its influence was variable. • Three consistent clusters, related to phenolic profiles, were detected among the cultivars. Phenolic compounds in virgin olive oil (VOO) contribute to its health properties, organoleptic features and oxidative stability. In this study, a total of 44 olive tree cultivars categorized by the International Olive Council to be among the most internationally widespread varieties were exhaustively and homogenously evaluated by analysis of the VOO phenolic profile during three consecutive crop seasons. Differences among cultivars resulted in up to 15-fold variations in the total phenol concentration. The 'cultivar' factor contributed the most to the variance (66.8% for total phenolic concentration) for almost all the phenols. However, the 'interannual variability' factor and the interaction 'cultivar x interannual variability' exhibited significant influences on specific phenols. According to the phenolic profile of the VOOs, we determined the presence of three groups of cultivars marked by the predominance of secoiridoid derivatives, which supports the phenolic profile as a criterion to be considered in olive breeding programs. [ABSTRACT FROM AUTHOR]

• Cobrançosa olives are richer in organic acids, esters and carbohydrates. • C.Serpa olives present higher levels of phenolic compounds. • Stress modulates olives' phenolic/lipophilic contents in a cultivar-dependent way. • C.Serpa olives have higher stress susceptibility than Cobrançosa and C.C.Branco. • Olives can be enriched in bioactive compounds in response to environmental stresses. The awareness of the functional and nutraceutical properties of olives and olive oil bioactive constituents contributed to oliviculture recent increase. Olives' metabolism and nutritional quality are determined by how the olive-tree is coping to climate change-related episodes, which increasingly occur in the Mediterranean. We characterize the most relevant lipophilic and phenolic compounds of olives from Olea europaea cultivars [Cobrançosa, Cordovil de Castelo Branco and Cordovil de Serpa (C.Serpa)] exposed to drought + heat. Olives from the three cultivars presented a similar qualitative profile but differed in their relative richness. Cobrançosa olives are richer in organic acids, esters and carbohydrates, while C.Serpa olives have higher levels of phenolic compounds, particularly under control conditions. Drought + heat changed the quantitative profile of olives, in a way dependent on the cultivar, and C.Serpa olives showed the highest stress susceptibility. Climate change-related conditions stimulate the accumulation of relevant bioactive compounds in olives, contributing to increasing its nutritional value. [ABSTRACT FROM AUTHOR]

• Malaxation time decreased the concentration of all phenols except oleocanthal and oleacein. • Vacuum conditions increased phenolic concentration. • Olive oil oxidative stability depends on individual phenols. Phenolic compounds largely contribute to the nutraceutical properties of virgin olive oil (VOO), the organoleptic attributes and the shelf life due to their antioxidant capabilities. Due to the relevance of malaxation in the oil extraction process, we tested the effects of malaxation time on the concentrations of relevant phenolic compounds in VOO, and we evaluated the influence of performing malaxation under vacuum. An increase in malaxation time significantly decreased the concentrations of aglycone isomers of oleuropein and ligstroside but, conversely, increased the oleocanthal and oleacein contents. Additionally, malaxation under vacuum led to an increase in phenolic contents compared to standard conditions carried out at atmospheric pressure. Finally, we explored the possibility of predicting the VOO oxidative stability on the basis of the phenolic profile, and a model (R 2 = 0.923; p < 0.0001) was obtained by combining the concentration of the VOO phenolic compounds and the main fatty acids. [ABSTRACT FROM AUTHOR]

• Olive (Olea europaea) is a rich source of valuable bioactive polyphenols. • Concentrations of 12 major polyphenols were measured. • Both of second-generation RNA-seq and full-length transcriptome were used. • 232 alternative splicing events were analyzed for the first time in olive. Olive (Olea europaea) is a rich source of valuable bioactive polyphenols, which has attracted widespread interest. In this study, we combined targeted metabolome, Pacbio ISOseq transcriptome, and Illumina RNA-seq transcriptome to investigate the association between polyphenols and gene expression in the developing olive fruits and leaves. A total of 12 main polyphenols were measured, and 122 transcripts of 17 gene families, 101 transcripts of 9 gene families, and 106 transcripts of 6 gene families that encode for enzymes involved in flavonoid, oleuropein, and hydroxytyrosol biosynthesis were separately identified. Additionally, 232 alternative splicing events of 18 genes related to polyphenol synthesis were analyzed. This is the first time that the third generations of full-length transcriptome technology were used to study the gene expression pattern of olive fruits and leaves. The results of transcriptome combined with targeted metabolome can help us better understand the polyphenol biosynthesis pathways in the olive. [ABSTRACT FROM AUTHOR]

• Phytochemical profile and antioxidant activity of Cornezuelo olives were studied. • Methanolic extracts were rich in secoiridoids, mainly oleuropein and comselogoside. • In vitro digestion reduced drastically the bioaccessibility of phenolics. • Considerable antioxidant activity was still observed after digestion. The main goals of this study were to determine the phenolic composition and antioxidant activity of table olives from Olea europaea L. cv. Cornezuelo, as well as the effect caused by a simulated in vitro digestion to evaluate compounds bioavailability. High-performance liquid chromatography with diode-array and mass spectrometry detection (HPLC-DAD-MSn) was used to evaluate the phytochemical profile, whereas conventional spectrophotometric methods (ABTS·+ and DPPH) were used to determine the antioxidant activity. The mineral content was also quantified by inductively coupled plasma – mass spectrometry. Thirty compounds were identified, mainly polyphenols, quantifying the major compounds by HPLC-DAD. After the simulated digestion, the phenolic content suffered an important decrease – more than 50% – reaching losses of up to 75% for oleuropein and comselogoside isomers. This decrease also resulted in a loss of antioxidant activity, observing significant differences for all parameters. However, the analyzed extracts still retained considerable antioxidant potential. [ABSTRACT FROM AUTHOR]