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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., 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., 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 © 2023. Published by Elsevier Ltd.)

'Corbella' is an ancient olive cultivar whose cultivation has recently been revived and hence little is known about its composition. This is the first work studying the metabolic profile of 'Corbella' olives during early maturation. Olives with a ripening index (RI) < 1 yielded considerably less oil content (<40%) but had more concentration of phenolic compounds (148.41-219.70 mg/kg), carotenoids (9.61-14.94 mg/kg) and squalene (521.41-624.40 mg/kg). Contrarily, the levels of α-tocopherol were higher at the RI of 1.08 and 1.96 (64.57 and 57.75 mg/kg, respectively). The most abundant phenolic compound was oleuropein aglycone (>50% of the phenolic composition), suggesting a high hydrolytic activity of β-glucosidase in the fruit. The antioxidant capacity was barely affected, while oleic/linoleic ratio reached its highest at RI of 1.96. Therefore, olives with an RI below 2 could be good candidates to produce high-quality olive oils with good level of stability., 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 © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The effect of granulometric fractionation and micronization of olive pomace (OP) on the biotransformation of phenolic compounds by intestinal microbiota was investigated in vitro. Three types of powdered OP samples were incubated with human feces to simulate colonic fermentation, after a sequential static digestion: non-fractionated OP (NF), granulometrically fractionated OP (GF) and granulometrically fractionated and micronized OP (GFM). GF and GFM favored the release of hydroxytyrosol, oleuropein aglycone, apigenin and phenolic acid metabolites in the first hours of colonic fermentation compared to NF (up to 41-fold higher). GFM caused higher release of hydroxytyrosol than GF. GFM was the only sample to release tyrosol and sustained tyrosol levels up to 24 h of fermentation. Micronization associated with granulometric fractionation was more efficient than granulometric fractionation alone to increase the release of phenolic compounds from the OP matrix during simulated colonic fermentation and can be further studied for nutraceutical purposes., 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 © 2023 Elsevier Ltd. All rights reserved.)

Blueberry anthocyanins (ANCs) are natural dietary bioactive colorants, but are unstable and easily degraded. To improve their stability, we constructed the nanocarriers for ANCs through an electrostatic self-assembly method, using chitosan (CS) and olive pectin (PC). Results showed that the CS-ANCs-PC nanocomplexes had nanoscale particle size (81.22 ± 0.44 nm), and an encapsulation efficiency of 91.97 ± 0.33% at pH 3.0, 1:1:5 ratio (m/v) of CS: ANCs: PC. Fourier transform infrared and UV-visible spectra demonstrated that ANCs can be embedded into the CS-PC carrier through electrostatic interaction. CS-ANCs-PC with stacked spherical particle structure had good thermal stability by scanning electron microscope and thermogravimetric analysis. Compared with free anthocyanins, CS-ANCs-PC possessed better DPPH· and ·OH scavenging activities, stronger environmental stability, and better targeted release in vitro digestion. This study may provide an important fundamental basis for improving the stability of anthocyanins in the blueberry industry., 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 © 2023 Elsevier Ltd. All rights reserved.)

Leaves incorporation during the extraction of olive oils can enhance their chemical-sensory quality. Thus, leaves from cvs. Arbequina or Santulhana were added (1%, w/w) during the extraction of Arbequina oils using an Abencor system, being discussed the impacts on the phenolics and volatiles formation enzymatic pathways. Leaves addition contributed to a significant decrease (P-value < 0.05) of the contents of secoiridoids (-11%), C6-aldehydes (-16%), and ester compounds (-22%). This could be tentatively related to a reduction of the enzymatic activity of secoiridoids biosynthesis and lipoxygenase pathways, promoted by the leaves' addition. Moreover, in the presence of leaves, the oils' total contents of phenolics and volatiles were significantly reduced (-7 and -17%, respectively). Contrary, the incorporation of leaves significantly increased (P-value < 0.05) the contents of C6-alcohols (+37%) and the intensities of the green fruity (+25%) and apple (+30%) sensations., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Due to the appreciable amounts of bioactive compounds in olive leaves and the effect of abiotic stresses on their synthesis, this study evaluated the metabolic profile of leaves of olive cultivars (Arbequina, Manzanilla and Picual) collected in four periods of the year (autumn, winter, spring and summer). The determination of the profile of bioactive compounds (phenolic compounds, flavonoids, tannins, carotenoids and chlorophylls) by spectrophotometry and the individual compounds by liquid chromatography coupled to mass spectrum, as well as antioxidant potential tests were performed. As results it was possible to observe that the leaves of the cultivar Manzanilla presented the highest levels of phenolic compounds and that the leaves collected in the summer presented a number of compounds much more relevant than the others. Thus, it was possible to conclude that the cultivar and the collection season significantly affect the bioactive content and the antioxidant potential of olive leaves., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The objective of this study was to evaluate the formation kinetics of polycyclic aromatic hydrocarbons (PAHs) during drying of olive pomace. It was dried at 170, 200 and 230 °C until the final moisture of 5%. PAH analyses were realized after certain drying times and moisture contents. Kinetics of the total PAH formation was comprised with the formation of PAH compounds through the drying process. The highest formation (2224 µg/kg) was observed at 200 °C and 5% moisture after 40 min. This also indicated the significance of drying time and evolution of temperature on the formation of PAH compounds. First order kinetic was applied to determine the kinetic constants as a function of temperature. Total PAH fomration rate constants (k) increased with the drying temperature. Activation energy (E a ) and frequency factor (k 0 ) values were determined to be 45.9 × 10 3 kJ/kg-mol and 18125.95 min -1 , respectively using the Arrhenius equation., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The effect of micronization of granulometrically fractionated olive pomace (OP) on the bioaccessibility of polyphenols and the antioxidant capacity was investigated during sequential in vitro static digestion. Crude OP was fractionated in a 2-mm sieve (F1: > 2 mm; F2: < 2 mm) and then micronized (300 r min -1 , 5 h) generating F1AG (17.8 μm) and F2AG (15.6 μm). Micronization increased the release of hydroxytyrosol, oleuropein, caffeic acid, and decarboxymethyl oleuropein aglycone (3,4-DHPEA-EDA) in the salivary and gastric phase, beyond luteolin in the gastric phase. Micronization also increased the intestinal bioaccessibility of hydroxytyrosol, 3,4-DHPEA-EDA, oleuropein, luteolin, and apigenin; it was more effective for F2AG than F1AG. Micronized samples increased antioxidant capacity in the gastric phase. F2AG exhibited the highest antioxidant capacity in the insoluble intestinal fraction. Thus, micronization can be further exploited to improve the nutraceutical properties of OP by increasing the bioaccessibility and antioxidant capacity of phenolic compounds., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

High vacuum technology has been incorporated into a new assisted extraction system applied to virgin olive oil (VOO) processing, which was tested at a lab-scale pilot plant to evaluate its impact on the physicochemical properties of the olive paste and oil. The vacuum system induced changes in the mechanical and structural properties of the olive cells, improving the coalescence of the oil droplets due to substantial cellular and intracellular mass transfer during the process, as shown by cryo-scanning electron microscopy (Cryo-SEM) analysis. The effects on the quality characteristics of VOOs extracted from three cultivars at different malaxation temperatures were evaluated. A significant increase in the phenolic content, from 25.2% to 48.6%, was observed. The content of volatile compounds responsible for the VOO flavor decreased as a function of malaxation temperature. The reduction of some volatile molecules related to the VOO off-flavor (ethanol, ethyl acetate and acetic acid) was also shown., (Copyright © 2020. Published by Elsevier Ltd.)

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., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The role of variety and effects of pickling on Egyptian olive fruit metabolome was determined using mass spectrometry-based metabolomics targeting nutrients and bioactive metabolities. The analyzed fresh olive fruit varieties included Manzanilo, Picual, Koroneiki, and Coratina, while the pickled samples included the Manzanilo and Picual varieties. Profiling of primary and secondary metabolites resulted in the detection of 201 metabolites. Variation between varieties was mostly observed among sugars, sugar alcohols, secoiridoids, and flavonoids. An abundance of carbohydrates and O-glycosides in Picual and Manzanilo versus enrichment of secoiridoids in Picual and Coratina olives viz. dehyro-oleuropein could account for the difference in palatability and health benefits among varieties. Herein, 13 new compounds are reported in the tested varieties, of which 10 appeared exclusively in pickled samples. Generally, pickled samples were characterized by the relative abundance of secoiridoids regarded as important markers for the pickling process. Metabolites profiling provided greater insight into the pickling process as a preservation method and accounted for the improved organoleptic characters in pickled fruits., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The two-phase technology for olive oil extraction generates large amounts of patè olive cake (POC), a by-product that is rich in bioactive health-promoting compounds. Here, response surface methodology (RSM) was used to maximize supercritical-CO 2 oil extraction from POC, while minimizing operative temperature, pressure and time. Under the optimal parameters (40.2 °C, 43.8 MPa and time 30 min), the oil yield was 14.5 g·100 g -1 dw (~65% of the total oil content of the freeze-dried POC matrix), as predicted by RSM. Compared with freeze-dried POC, the oil contained more phytosterols (13-fold), tocopherols (6-fold) and squalene (8-fold) and was a good source of pentacyclic triterpenes. When the biological effects of POC oil intake (20-40 µL·die -1 ) were evaluated in the livers of BALB/c mice, no significant influence on redox homeostasis was observed. Notably, a decline in liver triglycerides alongside increased activities of NAD(P)H:Quinone Oxidoreductase 1, Carnitine Palmitoyl-CoA Transferase and mitochondrial respiratory complexes suggested a potential beneficial effect on liver fatty acid oxidation., 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 © 2020 Elsevier Ltd. All rights reserved.)

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., 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 © 2020 Elsevier Ltd. All rights reserved.)

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., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Extra virgin olive oil (EVO) is among the most counterfeit foodstuffs in the present market. The Italian production is with no doubt one of the most valuable and therefore mostly counterfeit, due to the difficulty in checking the geographic provenance of olives. In order to provide a way for verifying the provenance of EVO, the role of microelements and, in particular, of lanthanides in the oil production chain has been studied. The distribution of lanthanides as determined by means of ICP-MS analysis appeared to provide a good tool for tracing the EVO production chain. Lanthanides and other microelements were then used for distinguishing a particularly prised EVO production from Liguria (northwestern Italy) made from Taggiasca olive variety, verifying that this production can be easily authenticated on the base of these chemical descriptors., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

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-MS n ) 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., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Olive leaves have become a promising source of phenolic compounds and flavonoids with high added value. Phenolic compounds and flavonoids are important sources of antioxidants and bioactives, and one of the processes used to effectively produce them is extraction via solvents, using aqueous ethanol solutions. To obtain the highest extraction yield per kg of biomass, olive leaves were extracted using a conventional technique (dynamic maceration) and an emerging technology, such as pressurized liquid extraction. Studies of the factors that influence these processes were performed: temperature, leaf moisture content, solvent/solid, and aqueous ethanol concentration were optimized using the central composite and Box-Behnken experiment designs. Pressurized liquid extraction resulted in more efficient oleuropein and luteolin-7-O-glucoside extraction than dynamic maceration. The operational conditions for maximizing the recovery of phenolic compounds and flavonoids and antioxidant capacity were determined to be 190 °C, leaf moisture content of 5%, and aqueous ethanol concentration of 80%., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Ultrasound-assisted extraction is an innovative technique applied to the extraction process for virgin olive oil (VOO), which is generally employed to increase plant efficiency and improve product quality. A high-power ultrasound (US) device was introduced at an industrial plant that can process at 2 tons/h to evaluate the technique's physicochemical impact on quality parameters of VOO that was caused by an intensive mass transfer induced by acoustic cavitation process and shockwaves. The impact on oil yield was also evaluated with respect to the ripening stage and malaxation time. No significant effects on the legal and commercial parameters of VOO (including quality indices, sterols, triterpene dialcohols, waxes and diacylglycerols) were found for olives at medium-early ripening stage. Significant physical changes, increased extraction yield (22.7%), enhanced phenol content (10.1%) were observed in US-VOO compared to control (C) oil extracted with a traditional process at an early maturity index., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Acrylamide and phenolic compounds on both fresh and cooked olives were monitored by HPLC/MS-MS and reversed-phase-HPLC methods along different procedures: elaboration process, high hydrostatic pressure (HHP), cooking treatment and bioavailability evaluation. Acrylamide was not detected during the elaboration process and after HHP treatment. Hydroxytyrosol, tyrosol, oleuropein and verbascoside were the most important phenols after HHP treatment. The frying and baking processes on olives enhanced the formation of acrylamide and a significant reduction in the phenolic compounds. The frying process produced lower acrylamide concentration and less reduction of phenolic compounds than the baking process, while in the gastrointestinal digestion these compounds were slightly reduced if compared to the initial stage. As a conclusion, the best way to ingest high quantities of phenols and reduce acrylamide consumption is by ingesting the olives when they are fresh. In case the olives need to be cooked, specific time and temperature conditions shall be applied., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The aim of this study was to prove the usefulness of multielements as provenance markers of olive oils by evaluating their link with soil composition and their discriminatory power. Eleven elements in twenty-one olive oils and their paired soils from four Tunisian regions were characterized. Chemometrics have been implemented for ICP-MS data processing. Principal component analysis identified the predominant geochemical source of the elements in the oils based on their associations according to Goldschmidt's rule. Although a clear correlation was not proven, correspondence was identified between the discriminating elements for both the soils and olive oils, which included Fe, Rb, Mg, and Pb. Linear discriminant analysis achieved classification and prediction rates of 92.1% and 87.3%, respectively. Our study substantiates the validity of multielements as markers of the olive oils' provenance, and that an elemental fingerprinting approach can be successfully applied in the construction of a database of Tunisian olive oils., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

To establish environmentally friendly polyphenolic extracts from grape and olive pomace, natural deep eutectic solvents (NADES) were used coupled with alternative energy sources - ultrasound and microwave irradiation. Obtained extracts were characterized by HPLC analysis, while antioxidant capacity was determined by ORAC method. Furthermore, in vitro cytotoxicity of prepared extracts was assessed by antiproliferation assay on two tumour cell lines, whereas for investigation of type of cell death or cell cycle arrest a flow cytometric analysis was applied. In addition, a detection of compounds with DNA/RNA-bindingaffinity in extracts was investigated by UV/Vis and circular dichroism spectroscopy. Grape pomace extract in NADES showed to be the best of all extracts tested, with regard to extraction of total polyphenolic compounds (p < 0.05) and related biological activities such as antioxidant and antiproliferative activity. Prepared polyphenolic extracts in NADES could be considered as ready-to-use in food and pharmaceutical industry without demanding and expensive downstream purification steps., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The interaction of strawberry cell wall with hydroxytyrosol (HT) and 3,4-dihydroxyphenylglycol (DHPG), two potent phenolic antioxidants naturally found in olive fruit with important biological properties, was investigated. The interaction occurred with drying and seemed to be more complex, strong and irreversible than a simple association. MALDI TOF-TOF analysis suggested covalent (ester bond) and non-covalent (strong hydrogen-bonding, mostly) interactions. The oxygen radical absorbance capacity (ORAC) assay confirmed that the phenols maintained partially their antioxidant activity after binding to the soluble dietary fraction. This soluble dietary fiber was obtained following digestion simulated in vitro with gastric and intestinal fluids. Although the antioxidant activity of HT and DHPG was affected by the dietary fiber interaction, this activity was restored when polysaccharide size was reduced by enzymatic treatment, suggesting that a similar process could occur in the colon. Thus, the use of this novel antioxidant-enriched soluble dietary fiber as a functional food ingredient could potentially promote intestinal health., (Copyright © 2018. Published by Elsevier Ltd.)

An olive leaf extract (OLE) was microencapsulated with sodium alginate (SA) by spray-drying to study the evolution of oleuropein (ORP) during in vitro gastrointestinal digestion, and its bioaccessibility and potential bioavailability from OLE and OLE-SA microparticles. Secoiridoids, flavonoids, simple phenols, oleosides and elenolic acid were identified in OLE. OLE/SA ratio 1:1.6 and inlet air temperature 135 °C were the optimal conditions for OLE-SA microparticles. ORP (70%) from OLE was degraded during gastric digestion, giving hydroxytyrosol and ORP-aglycone, whereas only the superficial ORP was released from microparticles. The remaining ORP from OLE was degraded under intestinal conditions, leading to oleosides; whereas alginate was swollen and disintegrated, releasing the ORP (90% of encapsulated ORP). ORP from both OLE and microparticles was degraded to hydroxytyrosol under colonic conditions. Encapsulation of OLE allowed the protection of ORP under gastric conditions and its controlled release at intestinal conditions, and higher bioaccessibility (58%) and potential bioavailability (20%)., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Olive oil phenolic compounds are receiving increased attention due to its influence on sensory characteristics and to scientific evidences of positive health effects. In this work, 28 ancient olive trees were selected and, during four consecutive seasons (2014-2017), oils were extracted and their phenolic fraction characterized. Hydroxytyrosol and tyrosol secoiridoids were the predominant groups, with contents between 32 and 496 mg of tyrosol equivalents/kg. Based on principal component analysis it could be concluded that the individual phenolic contents enabled the unsupervised grouping of olive oils by crop year. Furthermore, linear discriminant analysis allowed achieving sensitivities greater than 90%. It was shown that some specimens consistently allowed obtaining oils with high phenolic contents (≥500 mg tyrosol equivalents/kg). The identification of centenarian specimens for breeding based on their potential to produce oils with high levels of healthy compounds is of utmost interest, contributing to preserve the genetic heritage., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A single out-line HPLC-GC (FID) analytical method is applied to acquire the chromatographic fingerprint characteristic of the TMS-4,4'-desmetylsterol derivative fraction of several marketed edible vegetable oils in order to identify and discriminate the most valuable extra-virgin olive oils from the other vegetal oils (canola, corn, grape seed, linseed, olive pomace, peanut, rapeseed, soybean, sesame, seeds (non-specified composition but usually a blend of corn and sunflower) and sunflower). The natural structure of the preprocessed data undergoes a preliminary exploration using principal component analysis and heat map-based cluster analysis. A partial least squares-discriminant model is first trained from 53 oil samples (only 3 latent variables) and externally validated from 18 test oil samples. No classification errors are found and all the test samples are correctly classified. Additional classification models are also built in order to discriminate among vegetables-oil families and excellent results have been also achieved., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Hydrothermal pretreatments including steam explosion and subcritical water (SCW) facilitate hydrolyses of plant cell wall materials and supply environmentally friendly extraction solvents to recover value added compounds. In this study, effect of steam and SCW and temperature (160, 180 and 200 °C, 5 min) on yield and β-sitosterol content of pomace oil and phenolics were compared for value added utilization of olive pomace. Compared to acid hydrolysis, hydrothermal pretreatments yielded similar oil recovery. 54-76% of the bound oil and 18-32% of the bound β-sitosterol of the pomace were recovered by hydrothermal pretreatments. Steam pretreatment was more effective than SCW pretreatment at lower temperatures, however SCW showed increasing trend on oil yield related to steam pretreatment. As further research on process development, use of sequential temperature might be investigated, starting with steam explosion (<180 °C), followed by SCW pretreatment (>200 °C) to obtain multiple, aqueous and meal, fractions for total valorization of olive pomace., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The central reaction of chlorophyll (chl) breakdown pathway occurring during olive fruits maturation is the cleavage of the macrocycle pheophorbide a to a primary fluorescent chl catabolite (pFCC) and it is catalyzed by two enzymes: pheophorbide a oxygenase (PaO) and red chl catabolite reductase (RCCR). In subsequent steps, pFCC is converted to different fluorescent chlorophyll catabolites (FCCs) and nonfluorescent chlorophyll catabolites (NCCs). This work demonstrated that RCCR activity of olive fruits is type II. During the study of evolution of PaO and RCCR activities through the olive fruits maturation in two varieties: Hojiblanca and Arbequina, a significant increase in PaO and RCCR activity was found in ripening stage. In addition, the profile and structure of NCCs present in epicarp of this fruit was studied using HPLC/ESI-TOF-MS. Five different NCCs were defined and for the first time the enzymatic reactions implied in chlorophyll degradations in olive fruits elucidated., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The aim of this study was to discriminate the extra virgin olive oils (EVOO) based on quality characteristics, chemical composition and antioxidant activity according to ripening stages of olives. Two different olive varieties (Memecik and Gemlik) were obtained at different stages of ripening based on skin color (green, purple and black). Quality properties of olive oils; free fatty acidity, peroxide value, K232 and K270, purity properties; fatty acid and triacylglycerol (TAG) composition and antioxidant compounds like total phenol, carotenoid and chlorophyll content and antioxidant activity (oxidative stability, ABTS radical scavenging activity) analyses were performed. Higher amount of oleic, linoleic and palmitic acids were observed in olive oils. Oleic acid amount of olive oils decreased, linoleic acid increased with ripening. The most abundant TAG of olive oils were ECN 48, OOO, SLO+POO, ECN 46 and LOO/PLO. Olive oils were clearly classified by principal component analysis based on fatty acid and TAG composition., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The antioxidant activity of olive leaf (OL) and cake (OC) extracts with different solvents was evaluated. 70% of aqueous ethanol extract of OL was chosen as the most antioxidant extract based on antiradical activity (DPPH) (95.4±0.3%) and oxygen radical absorbance capacity (ORAC) (0.82±0.07g equivalent Trolox per g of solution) assays. This OL extract was incorporated in two multilayer materials consisting of (i) polyethylene/polyethylene (PE/PE) film and (ii) polyethylene/paper (PE/P). These multilayers were exposed to a gas stream enriched in free radicals to evaluate the scavenging capacity of both materials. PE/PE film exhibited the highest scavenging activity of free radicals (78.8%). Migration of the phenolic compounds from olive by-products into two simulants was performed and demonstrated a non-migrating behavior. The limits of detection and quantification for oleuropein were 0.5μgkg(-1) and 1.7μgkg(-1) and for Luteolin-7-O-glucoside 1.3μgkg(-1) and 4.3μg kg(-1) respectively., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The effect of modifying polyphenol oxidase (PPO) and peroxidase (POX) activity during the extraction of virgin olive oil has been assessed in terms of its influence on the phenolic profile of the oil produced. These enzymes were modified by adding exogenous enzyme or specific inhibitors during the milling and subsequent kneading step, studying the effect on specific phenolic compounds in the oils. PPO is the main enzyme involved in phenolic oxidation at the milling step whereas POX activity seems to be the main influence during the kneading step. The data obtained suggest it is possible to increase the nutritional and organoleptic quality of virgin olive oil by inhibiting these enzymes during olive fruit processing. Treatment with the PPO inhibitor tropolone produced a twofold increase in the phenolic fraction, which would therefore seem to be an interesting strategy to improve the nutritional and organoleptic properties of virgin olive oil., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Olive oils flavoured with edible herbs have grown in popularity because of their added value and potential health benefits. However, the combined presence of different phytochemicals from olive oil and herbs requires study of their possible interactions during intestinal transport and metabolism. The aim of this study was firstly to evaluate the effect on bioaccessibility of the co-occurring bioactive compounds from olive oil and thyme through an in vitro digestion model of three extracts: olive extract (OE), thyme extract (TE) and a combination of both (OTE). The bioaccessible fractions were exposed to Caco-2 and HepG-2 cell models, as well as to a co-culture of both of these. Results indicated that the bioaccessibility of hydroxytyrosol was enhanced when OTE was digested. After Caco-2 cells exposure, no significant differences were observed in hydroxytyrosol transport, whereas the main flavonoids from thyme seemed to undergo an enhanced basolateral permeation when both phenolic sources where exposed., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The influence of two operative parameters on the fermentation process of table olives from Taggiasca cultivar were investigated. Laboratory scale fermentations were performed using Lactobacillus plantarum as the only starter and in combination with Saccharomyces cerevisiae at three different temperatures (23, 30 and 37°C). Control tests used for each trial were fermented only by indigenous microflora. pH and phenolic compounds were monitored in the brine and olive flesh during the fermentation. Higher temperatures (37°C) enhanced notably the release of phenolic compounds in the brine. High performance liquid chromatography (HPLC) analysis of brines evidenced the complete hydrolysis of oleuropein after 100 days of fermentation at 37°C for all treatments. The antioxidant power of the extracts was linearly correlated to their polyphenol contents. The results confirmed the efficiency of treatments compared with the control tests for debittering process of table black olives. Phenolic compounds in the brines can be then extracted and used in food, cosmetic and pharmaceutical industries., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The antioxidant potential of dietary olive leaves or α-tocopheryl acetate supplementation on lipid oxidation of refrigerated stored hen eggs enriched with very long-chain n-3 fatty acids, was investigated. Ninety-six brown Lohmann laying hens, were equally assigned into three groups. Hens within the control group were given a typical diet containing 3% fish oil, whereas other groups were given the same diet further supplemented with 10 g ground olive leaves/kg feed or 200mg α-tocopheryl acetate/kg feed. Results showed that α-tocopheryl acetate or olive leaves supplementation had no significant effect on the fatty acid composition and malondialdehyde (MDA) levels of fresh eggs but reduced their lipid hydroperoxide levels compared to controls. Storage for 60 d decreased the proportions of polyunsaturated fatty acids (PUFAs) but increased those of monounsaturated fatty acids (MUFAs) in eggs from the control group, while had no effect on the fatty acid composition of the eggs from the other two groups, which showed decreased levels of lipid hydroperoxides and MDA. Therefore, the very long chain n-3 PUFAs in eggs were protected from undergoing deterioration partly by olive leaves supplementation and totally by α-tocopheryl acetate supplementation. In addition, incorporating tocopherols into eggs might also provide a source of tocopherols for the human diet., (Copyright © 2012 Elsevier Ltd. All rights reserved.)