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Phenolic Compounds Profile of Cornicabra Virgin Olive Oil
Abstract
This study presents the phenolic compounds profile of commercial Cornicabra virgin olive oils from five successive crop seasons (1995/1996 to 1999/2000; n = 97), determined by solid phase extraction reversed phase high-performance liquid chromatography (SPE RP-HPLC), and its relationship with oxidative stability, processing conditions, and a preliminary study on variety classification. The median of total phenols content was 38 ppm (as syringic acid), although a wide range was observed, from 11 to 76 ppm. The main phenols found were the dialdehydic form of elenolic acid linked to tyrosol (p-HPEA-EDA; 9 +/- 7 ppm, as median and interquartile range), oleuropein aglycon (8 +/- 6 ppm), and the dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA; 5 +/- 8 ppm). In many cases the correlation with oxidative stability was higher when the sum of the dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA) and oleuropein aglycon (r (2) = 0.91-0.96) or the sum of these two and hydroxytyrosol (r (2) = 0.90-0.97) was considered than was observed with HPLC total phenols (r (2)= 0.91-0.95) and especially with colorimetric determination of total polyphenols and o-diphenols (r (2) = 0.77-0.95 and 0.78-0.92, respectively). 3,4-DHPEA-EDA, p-HPEA-EDA, the aglycons of oleuropein and ligstroside, and HPLC total phenols content presented highly significant differences (p = 0.001-0.010) with respect to the dual- and triple-phase extraction systems used, whereas colorimetric total polyphenols content did not (p = 0.348) and o-diphenols showed a much lower significant difference (p = 0.031). The five variables that most satisfactorily classified the principal commercial Spanish virgin olive oil varieties were 1-acetoxypinoresinol, 4-(acetoxyethyl)-1,2-dihydroxybenzene (3,4-DHPEA-AC), ligstroside aglycon, p-HPEA-EDA, and RT 43.3 contents.
... Even if from the analysis of total phenols, with the colorimetric method, no statistically significant differences were observed between Ghiacciolo and its clone MAT 3 (Table 1), differences in the content of single phenols were revealed with the HPLC analysis. The colorimetric method is in fact less specific, measuring also compounds that do not possess antioxidant activity (Gómez-Alonso, Salvador, & Fregapane, 2002). In fact MAT 3 oil showed higher values of elenolic acid and oleuropein aglycone compared to the cultivar (Fig. 2). ...
... In fact MAT 3 oil showed higher values of elenolic acid and oleuropein aglycone compared to the cultivar (Fig. 2). As in the previous cases, also this clone seems to be characterized by higher nutritional value than the respective cultivar because high levels of elenoic acid imply a high antioxidant activity and a high oxidative stability (Gómez-Alonso et al., 2002). ...
... Free acidity specific for different cultivars (Brenes, García, Rios, García, & Garrido, 2002;Gómez-Alonso et al., 2002), in accordance with our findings. In order to identify the sensorial differences perceived in the oils produced by the cultivars and by their respective clones, the intensities of principal attributes like olive fruity (perceived both via gustatory and olfactory routes), bitter and pungent were submitted to PCA analysis (Fig. 4). ...
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.
... The lowest total phenol content was that of samples VII (1.08 mmol/kg) and VI (1.35 mmol/kg); however, the latter presented the highest content of free tyrosol (0.54 mmol/kg) and hydroxytyrosol (0.26 mmol/kg) and the lowest one of complex phenolic compounds (0.55 mmol/kg). As many authors have reported [20,29,30], o-diphenols are mainly responsible for the oxidative stability of virgin olive oils, and that is why these samples, which differ in the o-diphenol content, were chosen. Samples IV and V were very similar with respect to the o-diphenols and total phenol content; however, they presented very different complex/simple phenol ratios. ...
... Concerning phenolic compounds and their relationship with oxidative stability, the high correlation of these compounds has been widely reported, mainly o-diphenols with higher antioxidant capacity, with the induction period measured by Rancimat [30]. Nevertheless, this correlation is not simple and evident with the rate of oxidation at temperatures below 60 • C and neither with shelf-life determined by the oxidation parameters [18,31]. ...
The development of effective shelf-life prediction models is extremely important for the olive oil industry. This research is the continuation of a previous accelerated shelf-life test at mild temperature (40–60 °C), applied in this case to evaluate the oxidation effect of temperature on minor components (phenols, tocopherol, pigments) to properly complete a shelf-life predictive model. The kinetic behaviour of phenolic compounds, α-tocopherol and pigments during storage of different virgin olive oil samples at different temperatures (25–60 °C) is reported. Hydroxytyrosol, tyrosol and α-tocopherol fitted to pseudo-zero-order kinetics, whereas secoiridoid derivatives of hydroxytyrosol and tyrosol, o-diphenols and total phenols apparently followed pseudo-first-order kinetics. The temperature-dependent kinetic of phenolic compounds and α-tocopherol were well described by the linear Arrhenius model. The apparent activation energy was calculated. Principal component analysis was used to transform the considered compositional and degradation variables into fewer uncorrelated principal components resulting in 4: “no oxidizable substrate”, “initial oxidation state and conditions”, “free simple phenols”, and “degradation rates”. In addition, multivariate linear regression was used to yield several modelling equations for shelf-life prediction, considering initial composition and experimental variables easily determined in accelerated storage.
... Tyrosol has lower antioxidant activity than hydroxytyrosol (Mateos et al. 2003). Thus, hydroxytyrosol is decomposed before tyrosol during oxidation of olive oil (Gómez-Alonso et al. 2002). The level of tyrosol in olive oil remains steady in contrast to hydroxytyrosol (Hrncirik and Fritsche 2005). ...
... This indicated that antioxidant power of hydroxytyrosol was higher than tyrosol (Cheikhousman et al. 2005). Gómez-Alonso et al. (2002) reported that the high antioxidant activity of hydroxytyrosol favours its degradation and disappearance. Hrncirik and Fritsche (2005) reported that hydroxytyrosol was reduced during accelerated storage (60°C), while tyrosol showed high stability against oxidation. ...
The effects of thermal oxidation at 60 °C on tocopherols (α, β, γ) and phenolic compounds (hydroxytyrosol and tyrosol) of olive oil were studied. Tocopherols were determined by HPLC and phenolic compounds by HPLC and GC–MS. Peroxide value of olive oil increased with treatment time until it reached to 56.6 meq/kg. α-Tocopherol, β-tocopherol and γ-tocopherol contents of olive oil decreased with treatment time. α-Tocopherol in olive oil was decomposed after 63 days of treatment. β-Tocopherol in olive oil was depleted after 33 days of treatment. The reduction in γ-tocopherol of olive oil was 75% after 63 days of treatment. The degradation of hydroxytyrosol in olive oil was 91% after 63 days of treatment. Tyrosol was more stable than hydroxytyrosol in olive oil. Inverse correlations of peroxide value with hydroxytyrosol, α-Tocopherol, β-tocopherol and γ-tocopherol were observed.
... These phenolic compounds in VOO derive from those originally present in the olive fruits used for oil extraction but are substantially modified depending on the conditions used during extraction process and subsequent storage (Catalano et Caponio, 1996). Several studies have shown that concentration and composition of phenolic compounds in VOO are strongly affected by many agronomical and technological factors, such as olive cultivar , the place of Sonia Ben Temime and Hedia Manaî 366 cultivation (Vinha et al., 2005), the climate (Ben Temime et al., 2006), degree of maturation (Kalua et al., 2005), crop season (Gomez-Alonso et al., 2002), irrigation (Tovar, et al., 2001), the production process (Ranalli et al., 2001), storage methods and time since harvest Di-Givacchino et al., 2002;Guterréz et al., 2002;Rastelli et al., 2002;Okogeri et al., 2002;Mailer and Ayto, 2004;Cerretani et al., 2005;Fregapane et al., 2006;Kuala et al., 2006). Cooking methods have also been shown to alter phenolic concentrations in virgin olive oil Gomez-Alonso et al., 2003;). ...
... Ben Youssef et al. (2009) reported that the main phenolic alcohols in the studied Chétoui olive oils were hydroxytyrosol and tyrosol which were derived from the hydrolysis of oleuropein aglycon and ligstroside aglycon, respectively. With regard to their levels, hydroxytyrosol, the most active antioxidant phenolic compound (Bendini et al., 2007) was found at high concentration sometimes exceeding 230 mg kg −1 as compared to other Tunisian varieties (Abaza et al., 2005;Krichene et al., 2007) and Spanish varieties (Garcia et al., 2002, Gomez-Alonso et al., 2002 which did not exceed 10 mg kg −1 . ...
... There are also differences in profile, composition, and content of the individual phenolic compounds among different varieties of virgin olive oil (Gimeno et al., 2002). The phenolic content in virgin olive oils is affected by many factors, such as variety of olive fruit region of growth (Cerretani et al., 2005;Gomez-Alonzo et al., 2002;Vinha et al., 2005), agricultural techniques used to cultivate olive fruit (Bruni et al., 1994;Gomez-Rico et al., 2006;Romero et al., 2002), age of olive tree (Ayton et al., 2007), olive processing method, storage conditions, and extraction type Cerretani et al., 2005;Mailer and Ayton, 2004;Stefano et al., 1999), and the quantitative techniques for analysis of phenolic compounds from virgin olive oil (Carrasco-Pancorbo et al., 2005b). Fig. 10.3 illustrates classification of phenolic compounds in virgin olive oil based on chemical structure. ...
... Esterified phenolic acids are characterized by presence of hydroxyl groups attached to the aromatic hydroxyl group (Cicerale et al., 2009) The main classes of phenolic alcohols in virgin olive oil are hydroxytyrosol (2-[3,4-dihydroxyphenyl] ethanol) and tyrosol (p-hydroxyphenyl ethanol). The level of phenolic alcohol is present in low in fresh olive oil and its concentration increases during storage due to hydrolysis of olive oil secoiridoids Gomez-Alonzo et al., 2002). The level of hydroxytyrosol is considered as a sign of the degree of olive fruit maturation (Ryan and Robards, 1998). ...
... There are also differences in profile, composition, and content of the individual phenolic compounds among different varieties of virgin olive oil (Gimeno et al., 2002). The phenolic content in virgin olive oils is affected by many factors, such as variety of olive fruit region of growth (Cerretani et al., 2005;Gomez-Alonzo et al., 2002;Vinha et al., 2005), agricultural techniques used to cultivate olive fruit (Bruni et al., 1994;Gomez-Rico et al., 2006;Romero et al., 2002), age of olive tree (Ayton et al., 2007), olive processing method, storage conditions, and extraction type Cerretani et al., 2005;Mailer and Ayton, 2004;Stefano et al., 1999), and the quantitative techniques for analysis of phenolic compounds from virgin olive oil (Carrasco-Pancorbo et al., 2005b). Fig. 10.3 illustrates classification of phenolic compounds in virgin olive oil based on chemical structure. ...
... Esterified phenolic acids are characterized by presence of hydroxyl groups attached to the aromatic hydroxyl group (Cicerale et al., 2009) The main classes of phenolic alcohols in virgin olive oil are hydroxytyrosol (2-[3,4-dihydroxyphenyl] ethanol) and tyrosol (p-hydroxyphenyl ethanol). The level of phenolic alcohol is present in low in fresh olive oil and its concentration increases during storage due to hydrolysis of olive oil secoiridoids Gomez-Alonzo et al., 2002). The level of hydroxytyrosol is considered as a sign of the degree of olive fruit maturation (Ryan and Robards, 1998). ...
... There are also differences in profile, composition, and content of the individual phenolic compounds among different varieties of virgin olive oil (Gimeno et al., 2002). The phenolic content in virgin olive oils is affected by many factors, such as variety of olive fruit region of growth (Cerretani et al., 2005;Gomez-Alonzo et al., 2002;Vinha et al., 2005), agricultural techniques used to cultivate olive fruit (Bruni et al., 1994;Gomez-Rico et al., 2006;Romero et al., 2002), age of olive tree (Ayton et al., 2007), olive processing method, storage conditions, and extraction type Cerretani et al., 2005;Mailer and Ayton, 2004;Stefano et al., 1999), and the quantitative techniques for analysis of phenolic compounds from virgin olive oil (Carrasco-Pancorbo et al., 2005b). Fig. 10.3 illustrates classification of phenolic compounds in virgin olive oil based on chemical structure. ...
... Esterified phenolic acids are characterized by presence of hydroxyl groups attached to the aromatic hydroxyl group (Cicerale et al., 2009) The main classes of phenolic alcohols in virgin olive oil are hydroxytyrosol (2-[3,4-dihydroxyphenyl] ethanol) and tyrosol (p-hydroxyphenyl ethanol). The level of phenolic alcohol is present in low in fresh olive oil and its concentration increases during storage due to hydrolysis of olive oil secoiridoids Gomez-Alonzo et al., 2002). The level of hydroxytyrosol is considered as a sign of the degree of olive fruit maturation (Ryan and Robards, 1998). ...
... In the last decade, several analytical methods have been developed to determine individual phenolic components in VOO, mainly employing High Performance Liquid Chromatography coupled to Diode Array or Mass detectors (HPLC-DAD/MS) [8][9][10][11][12]; however, most of them are laborious and time consuming which is inconvenient for the olive oil sector. Moreover, the industry requires real time chemical composition information in order to be able to adapt technological parameters during processing to produce the desired product [13]. ...
... The elution protocol was as follows: min 0, 95% (A), 2.5% (B), and 2.5%(C); min 50, 34% (A), 33% (B), and 33% (C); min 52, 100% (B); min 65, 100% (B); min 68, 95% (A), 2.5% (B), and 2.5% (C) at 0,6 mL/min; min 72, 95% (A), 2.5% (B), and 2.5% (C) again at 1.0 mL/min. Polar phenolic compounds were quantified at 280 nm using syringic acid as an internal standard and response factors according to G omez-Alonso et al. [10]. ...
Chemometric analyses of near- (NIR) and middle-infrared (mid-IR) spectroscopy spectral data (12500–4000 cm−1 and 4000-400 cm−1) by Partial Least Square (PLS) regression combined with analytical determination of polar phenolic compounds measured by HPLC in different varieties, geographical origin and marketplace categories olive oils - Protected Denomination of Origin (PDO) “Montes de Toledo”; Galician; high quality extra virgin (‘Gourmet’/'Premium'); and commercial extra virgin and olive oils - were used to generate calibration and validation models in order to be able to predict the content and profile of these minor compounds, and thereby the quality of the product. Satisfactory multivariate test set validation algorithms were obtained for virgin olive oil (VOO)'s total polar phenolic (TPP) compounds (r = 0.91), hydroxytyrosol and tyrosol secoiridoid derivatives (HtyrSec, TyrSec; r = 0.91 and 0.92 respectively). Contrary to NIRS, the chemometric analysis of the mid-IR spectra gave no satisfactory validation models (r = 0.43, 0.54 and 0.66 for HtyrSec, TyrSec and TPP), despite that the calibration algorithms gave even higher correlation than NIRS (r > 0.96 for all the polar phenolics studied). Practical applications: The results establish that NIRS is a very useful technique that allows rapid screening of VOO samples to estimate polar phenolic profile, and thereby their quality and commercial grade. Furthermore, it may give real time information about olive oil composition during processing in order to automatically control technological parameters.
... In particular, tyrosol and vanillic acid concentrations were the highest in T, while p-coumaric and ferulic acid were highest in B. The tyrosol concentration was higher than that stated by Tovar et al. [73], who showed a concentration ranging between 0.23 mg kg −1 and 0.37 mg kg −1 depending on the irrigation method. Similarly, Gomez-Alonso et al. [74] showed a concentration ranging from 0.2 mg kg −1 to 6.1 mg kg −1 . The results are partially in accordance with Dini et al.'s [75], which showed a positive effect of the biostimulants on vanillic, ferulic, and p-coumaric contents, while the tyrosol concentration was reduced in their case. ...
Over the years, the use of biostimulants has become increasingly widespread due to
their proven efficiency in improving plant productivity and quality of fruits and mitigating the effects related to environmental stress. The aim of the present study was to evaluate the effect of three biostimulants on oil yield, production of drupes per plant, and nutraceutical components of olive drupes and oil (total polyphenols, anthocyanins, and fatty acids %) for “Racioppella” cultivar trees growing in South Italy (May–October 2021). The biostimulants used were: a tropical plants
extract (A) containing amino acids, vitamins, enzymes, phytochelatins, macro- and microelements, a glycine betaine-based product (B), and a Trichoderma spp.-based biostimulant (T). The three biostimulants were compared with a control thesis (C) treated only with water. T treatment increased the polyphenols content of olive drupes by 41.04% compared to C. A and B treatments increased
polyphenols content by 21.87% on average compared to C. All three biostimulants showed positive effect by increasing the amount of polyphenols in olive oil compared to C:T showed an increase of 32.19%, B 7.76%, and A 19.78%. Biostimulant application proved useful in boosting fundamental parameters that determine better drupe and oil in terms of antioxidant capacity and nutraceutical potential, other than an increased production.
... Representatives of another class of compounds, the phenolic alcohols, present in VOO are tyrosol (p-Hydroxyphenylethanol) and hydroxytyrosol (2-[3,4-dihydroxyphenyl] ethanol). They are present in low concentrations in fresh olive oil but tend to increase during the storage process due to the hydrolysis of secoiridoids [25]. ...
Hydroxytyrosol (HT) is an important marker for the authenticity and quality assessment of extra virgin olive oils (EVOO). The aim of the study was the qualitative and quantitative determination of hydroxytyrosol in commercial extra virgin olive oils of different origins and varieties using a newly developed biosensor based on a screen-printed electrode modified with single-layer carbon nanotubes and tyrosinase (SPE-SWCNT-Ty). The enzyme was immobilized on a carbon-based screen-printed electrode previously modified with single-layer carbon nanotubes (SPE-SWCNT-Ty) by the drop-and-dry method, followed by cross-linking with glutaraldehyde. The modified electrode surface was characterized by different methods, including electrochemical (cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS)) and spectrometric (Fourier transform infrared (FTIR) spectroscopy) methods. Cyclic voltammetry was used for the quantitative determination of HT, obtaining a detection limit of 3.49 × 10−8 M and a quantification limit of 1.0 × 10−7 M, with a wide linearity range (0.49–15.602 µM). The electrochemical performance of the SPE-SWCNT-Ty biosensor was compared with that of the modified SPE-SWCNT sensor, and the results showed increased selectivity and sensitivity of the biosensor due to the electrocatalytic activity of tyrosinase. The results obtained from the quantitative determination of HT showed that commercial EVOOs contain significant amounts of HT, proving the high quality of the finished products. The determination of the antiradical activity of HT was carried out spectrophotometrically using the free reagent galvinoxyl. The results showed that there is a very good correlation between the antiradical capacity of EVOOs, the voltammetric response and implicitly the increased concentration of HT. SPE-SWCNT-Ty has multiple advantages such as sensitivity, selectivity, feasibility and low cost and could be used in routine analysis for quality control of food products such as vegetable oils.
... These values are in the same order of magnitude as those reported for EVOOs obtained from the Cornicabra variety (633 mg GA/kg oil [56]; 556 mg GA/kg oil [25]; and 680 mg GA/kg oil [24]), and Picual variety (605 mg GA/kg oil [25]), both considered as the Spanish cultivars with the highest total phenolic content [57]. In addition, Nevadillo y Villalonga Spanish varieties (609 and 700 mg GA/kg oil, respectively), recently introduced in Argentina [58], and the Koroneiki variety, grown in Southern Spain (994 mg GA/kg oil [59]), also exhibited similar total phenolic content. ...
In this work, the quality and physicochemical parameters, phenolic composition, and antidiabetic potential of olive oils obtained from olives belonging to centenarian olive trees of the so-called ‘Mansa de Figueiredo’ cultivar were evaluated during three consecutive crop seasons (2017–2019). The oils produced during the three crop years were classified as extra virgin based on the quality-related indices, sensory analysis, and the genuineness-related parameters. In addition, LC-ESI-TOF MS was used to get a comprehensive characterisation of the phenolic fraction while LC-ESI-IT MS was applied for quantitation purposes. The content of phenolic compounds (ranging from 1837 to 2434 mg/kg) was significantly affected by the harvest year due to the environmental conditions and ripening index. Furthermore, although significant differences in the inhibitory effects against the α-glucosidase enzyme for the EVOOs extracted throughout the three successive years were detected, all the studied EVOOs exhibited a stronger inhibitor effect than that found for acarbose.
... Our findings reinforce the evidence that HT may be a reliable marker to detect aged EVOO samples and blends prepared with aged EVOO as recently reported [5]. In this context, the increase of HT content has been associated with the hydrolysis of the olive oil secoiridoid aglycons during storage, which are transformed into hydrophilic molecules such as HT and consequently, enhancing its content [33,34]; therefore, the EVOO freshness should be correlated to a lower and not to the higher value of HT [30]. Nevertheless, other potential variations in the free HT and HT-FAs content of olive oil may be associated with other parameters such as the cultivar, geographic origin, altitude, edaphoclimatic conditions, time of harvest, degree of maturation of the olive fruits, as well as, aging with different storage conditions (exposure to oxygen, light, and temperature) and research effort should be performed to establish the range of HT-FAs concentration that is present in fresh and old olive oil samples for authentication purposes. ...
Recently, lipophenols (or phenolipids), which are composed of a fatty acid (FA) and a phenolic core such as hydroxytyrosol (HT), have been detected in extra virgin olive oils (EVOO), promoted by the esterification reaction between FA and HT in a unique lipophenolic molecule (HT-FAs). However, the levels of HT-FAs, as well as potential alterations in their concentrations during the storage of EVOO, are still unexplored. Thus, the present study uncovers, by UHPLC-MS/MS triple quadrupole analyzer, the changes of HT-FA levels in extra virgin olive oil (EVOO) during 12 months of storage, mimicking both commercial temperatures (room temperature (RT)), as well as inappropriate conditions of storage at high temperatures (40 °C). In addition, levels of HT-FAs in olive oils (blends with refined olive oil) compared to EVOO were assessed to investigate the effect of the refining process on lipophenol generation. Free HT concentration in EVOO was increased, after 12 months, by 121.31% and 236.80% at RT and 40 °C, respectively. Additionally, HT-FAs in EVOO samples, mainly, esterified with linoleic acid and oleic acid, enhanced up to 2.6-fold and 5.5-fold, respectively after 12 months at 40 °C. Nonetheless, in blends with refined oils, the levels of free HT decreased by 80.2 %, whereas esterified HT augmented significantly. The type of FA linked to HT core, as well as the degree of unsaturation of FA seem to influence the lipophenolic derivative generation. Significant concentration differences found during storage time supported their potential use as candidate markers, but these findings so require further assessment to establish the HT-FAs concentration range for authentication purposes. Likewise, the ratio between esterified/free HT could be employed as freshness or aging indices of the EVOO during its shelf life, when used in conjunction with validated olive quality parameters.
... However, sterol composition alone was not enough to distinguish EVOOs from Manzanilla Cacereña cultivar from EVOOs from other cultivars (Diaz et al., 2005). Different varieties will present different enzymatic activities, which result in different volatile and phenolic profiles; those have also been used to discriminate between varieties (Gómez-Alonso et al., 2002;Haddada et al., 2007). In addition, tocopherols, pigments, and hydrocarbons are also affected by the olive enzymes, which depend on the cultivar; hence, those markers have been used successfully as well as discriminants between different olive cultivars (Baccouri et al., 2007;Bueno et al., 2005;Giuffrida et al., 2007). ...
The growing demand for extra virgin olive oil (EVOO), appreciated for its unique organoleptic properties and health benefits, has led to various fraudulent practices to maximize profits, including dilution with lower value edible oils. The adulterated oils would be of poor nutritional quality, more readily oxidized, and may contain unhealthy substances formed during processing. Nevertheless, the range of available techniques to detect fraud in EVOO production has been growing. Reliable markers of EVOO adulteration include fatty acids and minor components such as sterols, tocopherols, triterpene alcohols, phenolic compounds, phospholipids, volatile compounds, and pigments. Additionally, increasing consumer interest in high‐quality EVOO has led to the development of robust scientific methods for its traceability. This review focuses on (i) the usefulness of certain compounds as markers of EVOO adulteration; (ii) the potential health risks of consuming adulterated EVOO; and (iii) reliable methods for the geographical traceability of olive oil. In conclusion, fraudulent production practices need to be detected to preserve the beneficial health effects of EVOO and to avoid the potential risks associated with ingesting substandard oil. In this work, as EVOO certification and regulatory framework limitations have already been extensively reviewed, we focus our attention on biomarkers that guarantee both the authenticity and traceability of oil, and consequently its health properties. When it is unavailable to obtain a high‐resolution mass spectrometry full fingerprint, stigmastadienes and the sterolic profile are proposed as reliable markers.
... Peanut is included among the richest healthy oil products, which are resistant to rancidity (Gantait et al., 2019). Its high nutritional value is also due to the significant presence of biologically active compounds (Gomez-Alonso et al., 2002;Tuberoso et al., 2007), whereas the oil content and composition represent a shelf-life index (Campos-Mondragòn et al., 2009). Magnesium, phosphorus, calcium and potassium are the major mineral elements in the seeds (Asibuo et al., 2008). ...
With the perspective of reintroducing peanut cultivation in southern Italy about six decades after its dismissal, research was carried out with the aim to identify the best performing farming manage-ment in terms of yield and quality. In this respect, the effect of the factorial combination between four plant densities (6.1, 7.8, 10.3, and 12.1 plants m-2) and two harvest times (100 and 110 days after plant-ing) was assessed on pod and seed yield, as well as on seed quality, antioxidant activity, and elemental composition. The later harvest time determined a 26.9% dry weight increase, but a 14.3% decrease in the number of seeds per pod. Plant density significantly influenced all the yield and growth indices except for mean seed weight. Yield and growth of each plant were best affected by the lowest plant density, whereas the opposite trend was recorded for the same parameters referred to the surface area unit. The density of 12.1 plants m-2 resulted in a 32% reduction in pods per plant compared to 6.1 plants m-2, but had the greatest effect on seed production per m2. The leaf area index was the highest with the density of 12.1 plants m-2. The total dry weight increased by 1.7-fold from 6.1 to 12.1 plants m-2. Compared to the first harvest time, in the second one the protein content decreased by 6.8%, and total polyphenols and antioxidant activity decreased by 11.2% and 7.6%, respectively. The second harvest time led to a deple-tion of N, P, and Mg, by 6.8%, 6.2%, and 6.8%, respectively, and a 7.1% Ca increase. The reintroduction of peanut cultivation in southern Italy is a realistic goal, though further studies regarding the crop system management are needed
... Finally, the principal phenolic alcohols found in EVOO are tyrosol (p-Hydroxyphenyl ethanol) and hydroxytyrosol (2-[3,4-Dihydroxyphenyl] ethanol). These are present in small concentrations in fresh olive oil but tend to increase along the storage process because of the hydrolysis of olive oil secoiridoids [94]. ...
1) Background: Extra virgin olive oil (EVOO) is responsible for a large part of many health benefits associated to Mediterranean diet as it is a fundamental ingredient of this diet. The peculiarities of this golden, highly valued product are in part due to the requirements that must be met to achieve this title, namely, it has to be obtained using exclusively mechanical procedures, its free acidity cannot be greater than 0.8%, it must not show sensory defects, and it has to possess a fruity taste. (2) Methods: All these characteristics are key factors to EVOO quality, thus the chemical composition of these many health-promoting compounds, such as unsaturated fatty acids (which are also the major compounds, especially oleic acid), as well as minor components such as tocopherols or phenolic compounds (which behave as natural antioxidants) must be preserved. (3) Results: Due to the presence of all these compounds, the daily consumption of EVOO entails health benefits such as cardioprotective, antioxidant, anti-inflammatory, anti-tumor properties or acting as regulator of the intestinal microbiota, among others. (4) Conclusions: Taking all together, conserving EVOO chemical composition is essential to preserve its properties, so it is worth to control certain factors during storage like exposure to light, temperature, oxygen presence or the chosen packaging material, to maintain its quality and extend its shelf-life until its consumption.
... [58]. This is the first report of the presence of these tyrosol derivatives in seaweed, while 3,4-DHPEA-AC was previously reported by Gomez-Alonso, et al. [59] in Cornicabra olive oil variety. ...
Seaweed is an important food widely consumed in Asian countries. Seaweed has a diverse array of bioactive compounds, including dietary fiber, carbohydrate, protein, fatty acid, minerals and polyphenols, which contribute to the health benefits and commercial value of seaweed. Nevertheless, detailed information on polyphenol content in seaweeds is still limited. Therefore, the present work aimed to investigate the phenolic compounds present in eight seaweeds [Chlorophyta (green), Ulva sp., Caulerpa sp. and Codium sp.; Rhodophyta (red), Dasya sp., Grateloupia sp. and Centroceras sp.; Ochrophyta (brown), Ecklonia sp., Sargassum sp.], using liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS). The total phenolic content (TPC), total flavonoid content (TFC) and total tannin content (TTC) were determined. The antioxidant potential of seaweed was assessed using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, a 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) free radical scavenging assay and a ferric reducing antioxidant power (FRAP) assay. Brown seaweed species showed the highest total polyphenol content, which correlated with the highest antioxidant potential. The LC-ESI-QTOF-MS/MS tentatively identified a total of 54 phenolic compounds present in the eight seaweeds. The largest number of phenolic compounds were present in Centroceras sp. followed by Ecklonia sp. and Caulerpa sp. Using high-performance liquid chromatography-photodiode array (HPLC-PDA) quantification, the most abundant phenolic compound was p-hydroxybenzoic acid, present in Ulva sp. at 846.083 ± 0.02 μg/g fresh weight. The results obtained indicate the importance of seaweed as a promising source of polyphenols with antioxidant properties, consistent with the health potential of seaweed in food, pharmaceutical and nutraceutical applications.
... mg Gallic acid /100 g oil respectively, The results of the statistical analysis showed significant differences in total phenol content at probability level (P <0.05). these results came close to what [26] in a study showed that the total content of phenols in okra seed powder ranged from 34.89 -39.39 mg / 100g of seeds, this is due to the difference of varieties, which leads to a difference in phenolic content as well as the method of extraction influence and environmental conditions" on that, While [27] mentioned the total phenolic content of okra seed powder defatted 24.25 mg / kg, While the total phenolic content of non-defatted okra seed powder 25.24 mg / kg, As for [28] The total phenolic content of Okra fruits 10.75 mg /Gallic Acid / 100 g, while the total phenolic content of okra seeds was 142.48 mg /Gallic Acid / 100 g, And [29] showed the total content of phenols in okra seeds was 56.06 mg/ Gallic Acid / 100 g, while [30] indicated that okra seeds had a total phenolic content of 1460-185 mg / Gallic Acid / 100 g, when compared with the total phenolic content of the oil okra seeds with that found [31] on the total phenolic content of olive oil 168.53 mg / kg, Phenolic compounds play an important role in contributing to the smell and flavor of the oil and its effect on its stability and stability as antioxidants that protect the oils from the effects of oxidation side effects resulting which make them undesirable and affect the quality and quality of those oils [32], while [33] in the study of phenolic compounds in virgin olive oil that the high content of phenolic compounds act as natural antioxidants increase the resistance of oil for storage and higher temperatures In addition, phenols are the main contributor to the taste of olive oil as well as "its role in the prevention of many Of human diseases. ...
This study aimed to determination the nutritional and vitamin E analysis of the three Iraqi cultivars of okra( Abelmoschus esculentus L.) seeds oil. The phenolic compound, chlorophyll, carotenoid and minerals (Fe ,Zn ,Ca ,K, Mg, Na, P) were determined in okra seeds oil. The oil from A. esculentus seeds were extracted using Bligh and Dyer with chloroform: methanol (1:1). The mean values of total phenolic, the results of this study the husayniyah seeds oil contained the highest pheolic content (34.73mg Gallic acid/100g oil) and chlorophyll and caroteniod (2.295, 2.813mg/kg oil) in husayniyah respectively. Batera seed oil had the highest percentage of vitamin E (3861.347 ppm) when estimation vitamin HPLC. The results showed that petra seed oil had the highest Mg(321 ppm) while phosphorus was (382.799ppm) in husayniyah
(3) (PDF) IOP Conference Series: Earth and Environmental Science The nutritional composition and vitamin E of three Iraqi okra (Abelmoschus esculentus L.) seeds oil The nutritional composition and vitamin E of three Iraqi okra ( Abelmoschus esculentus L.) seeds oil. Available from: https://www.researchgate.net/publication/337830960_IOP_Conference_Series_Earth_and_Environmental_Science_The_nutritional_composition_and_vitamin_E_of_three_Iraqi_okra_Abelmoschus_esculentus_L_seeds_oil_The_nutritional_composition_and_vitamin_E_of_thre#fullTextFileContent [accessed May 13 2020].
... mg Gallic acid /100 g oil respectively, The results of the statistical analysis showed significant differences in total phenol content at probability level (P <0.05). these results came close to what [26] in a study showed that the total content of phenols in okra seed powder ranged from 34.89 -39.39 mg / 100g of seeds, this is due to the difference of varieties, which leads to a difference in phenolic content as well as the method of extraction influence and environmental conditions" on that, While [27] mentioned the total phenolic content of okra seed powder defatted 24.25 mg / kg, While the total phenolic content of non-defatted okra seed powder 25.24 mg / kg, As for [28] The total phenolic content of Okra fruits 10.75 mg /Gallic Acid / 100 g, while the total phenolic content of okra seeds was 142.48 mg /Gallic Acid / 100 g, And [29] showed the total content of phenols in okra seeds was 56.06 mg/ Gallic Acid / 100 g, while [30] indicated that okra seeds had a total phenolic content of 1460-185 mg / Gallic Acid / 100 g, when compared with the total phenolic content of the oil okra seeds with that found [31] on the total phenolic content of olive oil 168.53 mg / kg, Phenolic compounds play an important role in contributing to the smell and flavor of the oil and its effect on its stability and stability as antioxidants that protect the oils from the effects of oxidation side effects resulting which make them undesirable and affect the quality and quality of those oils [32], while [33] in the study of phenolic compounds in virgin olive oil that the high content of phenolic compounds act as natural antioxidants increase the resistance of oil for storage and higher temperatures In addition, phenols are the main contributor to the taste of olive oil as well as "its role in the prevention of many Of human diseases. ...
This study aimed to determination the nutritional and vitamin E analysis of the three Iraqi cultivars of okra (Abelmoschus esculentus L.) seeds oil. The phenolic compound, chlorophyll, carotenoid and minerals (Fe, Zn, Ca, K, Mg, Na, P) were determined in okra seeds oil. The oil from A. esculentus seeds were extracted using Bligh and Dyer with chloroform: methanol (1:1). The mean values of total phenolic, the results of this study the husayniyah seeds oil contained the highest pheolic content (34.73mg Gallic acid/100g oil) and chlorophyll and caroteniod (2.295, 2.813mg/kg oil) in husayniyah respectively. Batera seed oil had the highest percentage of vitamin E (3861.347 ppm) when estimation vitamin HPLC. The results showed that petra seed oil had the highest Mg(321 ppm) while phosphorus was (382.799ppm) in husayniyah.
... Il genotipo influenza la composizione di acidi grassi degli oli nonché la quantità e qualità dei composti fenolici e volatili e quindi le caratteristiche organolettiche [7][8][9]. Il profilo fenolico di drupe e rispettivi oli è qualitativamente influenzato dalla cultivar [10][11][12]. Ad esempio, l'oleuropeina è pressoché presente nelle drupe di tutte le cultivar mentre, al contrario, la demetiloleuropeina ed il verbascoside sono cultivar-dipendenti tanto da essere stati proposti come marcatori per l'origine genetica dei frutti [13]. ...
Despite the great number of minor and local olive cultivars, oil extraction at industrial level is carried out mainly using few major varieties. Biodiversity is one of the strength point of olive oil sector to characterize, distinguish, and valorise olive oil productions. In this study, we report the maturation pattern of the drupes and characterize the virgin olive oil obtained from Bambina cultivar, a local variety from Gravina di Puglia, in province of Bari. The name of the cultivar, which means "child", should arise from the ancient use of its oil, appreciate by child because only slightly bitter and pungent. Nonetheless, it is characterized by high total phenolic content. The obtained results support the traditional and local knowledge and gave one first scientific explanation of it. Indeed, despite the significant content of phenols (about 400 mg kg-1) oleochantal, main responsible of pungent taste, represents about 1% of the total phenols. On the contrary, great amount of flavonoids has been detected. Remarkable is also the content of other lipophilic antioxidants, tocopherols and carotenoids.
... It is widely known that composition and antioxidant properties of EVOO may be affected by several agronomic factors, such as cultivar, fruit ripening stage and agroclimatic conditions [5,12,13]. The olive ripeness and the cultivar have been described as the most important factors affecting the EVOO phenolic profile [14,15], while organoleptic characteristic such flavour have been linked to geographic and climatic factors more than to cultivar or ripening stage [13,16]. Nevertheless, studies about how these aspects could affect the bioaccessible fraction of EVOO are still very scarce. ...
The health benefits of extra virgin olive oil (EVOO) are related to its chemical composition and the presence of bioactive compounds with antioxidant properties. The aim of this study was to evaluate antioxidant compounds (pigments, coenzyme Q10 (CoQ10) and phenolic compounds) and antioxidant properties of EVOO from the same region comparing different cultivars (Hojiblanca and Arbequina), harvest year and crop stage. Antioxidant properties of oils were studied before and after a gastrointestinal digestion process, by in vitro assays (DPPH, ABTS and FRAP) and antioxidant markers in Caco-2 cells (reactive oxygen species production). The content of bioactive compounds measured was significantly affected by cultivar and harvest year (except for carotenoids) and by the crop stage (except for coenzyme Q10). Higher amounts of coenzyme Q10 were observed in Hojiblanca than in Arbequina EVOO. Total phenol content and antioxidant properties were also different depending on cultivar and harvest year and the in vitro digestion process strongly improved antioxidant marker values. Antioxidant potential in bioaccessible fractions was mainly related to the content of coenzyme Q10 and phenolic compounds in EVOO. Chemometric analysis showed that the oils were clearly classified by cultivars, harvest and crop stage, according to the chemical composition and antioxidant activity analyzed in the present study.
... Il genotipo influenza la composizione di acidi grassi degli oli nonché la quantità e qualità dei composti fenolici e volatili e quindi le caratteristiche organolettiche [7][8][9]. Il profilo fenolico di drupe e rispettivi oli è qualitativamente influenzato dalla cultivar [10][11][12]. Ad esempio, l'oleuropeina è pressoché presente nelle drupe di tutte le cultivar mentre, al contrario, la demetiloleuropeina ed il verbascoside sono cultivar-dipendenti tanto da essere stati proposti come marcatori per l'origine genetica dei frutti [13]. ...
The present work was aimed at evaluating the effect of the addition of monoacylglycerols (MAG) with different fatty acid composition, thus obtained from different vegetable oils such as olive (OO), soybean (SO), and palm (PO). The MAG were added in the purified olive oil at different concentrations (5, 15, and 30 mg/g) and consequently the oxidative process was monitored. For this purpose, the purified oil added with MAG was subjected to oven test for 28 days, during which multiparametric analysis of oxidation was carried out: peroxide value, spectrophotometric constants (K270, K232), oxidized triacylglycerol, and triacylglycerol oligopolymers. Our results showed that both OO and SO MAG significantly slowed the oxidative processes after 15 days, in a dose-dependent manner. For PO MAG, on the other hand, although the dose dependent effect was less evident, an antioxidant effect was observed that was greater than that observed for the other MAG, which was already detectable in the early stages of oven test.
... Given this assumption, several researchers have tried to find which of the mentioned substances is more correlated with oxidative stability. A number of studies have demonstrated that polyphenol contents are, among the minor compounds, the group more correlated with this parameter [88]. The antioxidant behavior of tocopherols represents a complicated phenomenon as they are efficient antioxidants at low concentrations, but they steadily lose efficiency as their oil content in the vegetables increases [76]. ...
Yield and quality of fruits are multifaceted traits involving various plant and fruit processes that, for a given genetic makeup, depend on environmental factors and agronomic practices. Crop yield has to meet the demand of a growing population , but crop quality is a challenging issue affected by consumer's behavior and increasingly associated with food security. The projected climate scenario for South Mediterranean Europe predicts lower precipitation and higher temperatures that will negatively affect agricultural activity. A warmer and drier climate is expected to cause changes in crop yield and its quality. Higher temperatures affect photosyn-thesis, causing alterations in sugars, organic acids, flavonoid contents, firmness, and antioxidant activity. Reduced soil water availability will impact on the capacity of plants to accumulate biomass and when conjugated with warmer weather, it can trigger disorders like fruit sunburn further depressing crop yields. New cultivation techniques are necessary to produce sufficient food supplies to meet the basic nutrient requirements of the growing human population and support the agriculture economy. We focus on the production of olives and wine grapes, two of the most cultivated fruit crops of Southern Europe, which is certainly strongly affected by changing weather conditions. We review the recent developments on agronomic practices to counter or minimize the projected environmental changes, and we will report on our own experiences.
... It is worth to underline that orthodiphenol contents thus determined were in good enough agreement (±14%) with those found by analyzing the same samples with the sodium molybdate colorimetric approach [51,52]. ...
A simple, effective and low-cost technique is here presented for assembling flexible and robust electrochemical devices on transparent PVC supports, using ordinary tools, all installed on a commercial desktop digitally controlled plotter/cutter. Small diamond burs were first set up to rough precise and well defined patterns on the surface of smooth and flexible PVC transparent films. Subsequently, reference, counter and working carbon electrodes were drawn onto abraded patterns by using micropencils (4B graphite leads, 0.5 mm in diameter), in their turn installed on the plotter/cutter. The effective active working surface of electrochemical cells was then defined by a thin adhesive strip or by covering the patterned support with a suitably cut adhesive layer, depending upon whether they were intended for use in batch or drop mode. After optimization of fabrication parameters, such as pressure and speed adopted during bur abrasion and pencil drawing, the electrochemical characterization of these cells was performed by using potassium hexacyanoferrate(II) as redox probe. Voltammetric responses displayed a good inter-device reproducibility (5.6%), thus confirming the effectiveness of this easy and fast assembling strategy. These PVC-based pencil-drawn electrochemical cells were then integrated as thin-layer detectors in adhesive-tape based microfluidic channels, cut and prepared in their turn using the digitally controlled plotter/cutter. These detectors offer the advantage given by the impermeability of PVC supports, thus avoiding absorption of the flowing carrier and consequent analyte broadening, instead occurring when electrochemical cells are pencil drawn on hydrophilic materials as paper. After optimization of the complete fabrication process, the effectiveness of these devices was tested by a proof-of-concept direct quantification of ascorbic acid in commonly used drugs.
... The fact that Ac-Pin was below the quantification limit in both oils could be considered as a typical feature of the Galician olive oils under study. It is well-known that in other common varieties from Spain, such as 'Cornicabra' oil, the lignans concentration levels are considerably higher (Gómez-Alonso, Salvador, & Fregapane, 2002). ...
‘Brava’ and ‘Mansa de Figueiredo’ extra-virgin olive oils (EVOOs) are two varieties identified from north-western Spain. A systematic phenolic characterization of the studied oils was undertaken by LC-ESI-IT-MS. In addition, the role of dietary polyphenols from these EVOOs has been evaluated against the inhibition of key enzymes (α-glucosidase and α-amylase) in the management of diabetes mellitus (DM). Oleuropein and ligstroside derivatives comprised 83% and 67% of the total phenolic compounds in ‘Brava’ and ‘Mansa de Figueiredo’ EVOOs, respectively. The main secoiridoids from oleuropein were DOA (3,4-DHPEA-EDA, 59 and 22 mg kg⁻¹, respectively) and the main isomer of OlAgl (3,4-DHPEA-EA, 74 and 23 mg kg⁻¹). The main secoiridoids from ligstroside were D-LigAgl (p-HPEA-EDA or oleocanthal, 23 and 167 mg kg⁻¹) and the main isomer of LigAgl (p-HPEA-EA, 214 and 114 mg kg⁻¹). For α-glucosidase, both EVOO extracts displayed stronger inhibitory activity (IC50 values of 60 ± 8 and 118 ± 9 μg mL⁻¹, respectively) than the commercial inhibitor acarbose (IC50 = 356 ± 21 μg mL⁻¹). Nevertheless, for α-amylase, only ‘Brava’ extracts showed anti-α-amylase capacity. A daily VOO intake lower than the requirements of EFSA seem to be enough to reach both 50% for α-glucosidase and 25% for α-amylase inhibition. These findings support the potential health benefits derived from Galician EVOOs that might be probably linked to the outstanding high concentration levels of phenolic acids and flavonoids.
... It is worth to underline that orthodiphenol contents thus determined were in good enough agreement (±14%) with those found by analyzing the same samples with the sodium molybdate colorimetric approach [51,52]. ...
A simple and sensitive device is presented based on the use of pencil-drawn paper based electrochemical detector placed at the end of a cotton thread fluidic channel in wall-jet configuration. This innovative and fast responding electroanalytical system can be adopted for both single and dual electrode electrochemical detection, this last achieved by applying two different potentials at two independent working electrodes drawn on the opposite faces of the paper based detector. Its performance was preliminarily optimized by adopting hexacyanoferrate(II) as probe species undergoing reversible electrochemical processes. These devices were then used for the single electrode detection of ascorbic acid in aqueous samples and the dual electrode detection of orthodiphenols in extra virgin olive oils (EVOOs). In fact, these devices enable hydrophilic orthodiphenols, typically present in EVOOs (extracted by a 80:20% v/v acetonitrile/water mixture), to be discriminated from hydrophilic monophenols instead present in almost all vegetable oils. Flow-injections runs were conducted by using a 0.01 M H2SO4 + 0.5 KCl running electrolyte allowing the rapid and selective detection of hydrophilic orthodiphenols with satisfactory sensitivity and a low enough detection limit (2 μM). Different real samples of EVOOs and sunflower oils were analyzed. Abundant enough contents of orthidiphenols were found in EVOO samples, while no trace of these antioxidants was found in sunflower oils.
... The first group was the Tarom varieties (T) and consisted of nine Iranian olive varieties including T10, T15, T16, T17, T18, T20, T22, T23, and T24. The second group consisted of four Mediterranean varieties including Koroneiki and Arbequina, selected for the relatively high and low content of oleic acid in their oil, respectively (Parvini et al., 2015;Homapour et al., 2016 Picual, selected for their high phenolic contents ( Gómez-Alonso et al., 2002;Beltrán et al., 2004). The third group consisted of three major varieties in Iran including Zard, Mari, and Rowghani. ...
Background: According to the epidemiological studies, consuming olive products can decrease the incidence of the different
types of cancers mostly due to the high anti-oxidant properties of their polyphenolic compounds.
Objectives:To evaluate the anti-oxidant and anti-proliferative potentials of the olive fruits total polyphenols on the gastric adenocarcinoma MKN45 cells in comparison to the normal Hu02 cells.
Results:Treatment of the MKN45 cells with the phenolic compounds extracted from olive fruits decreased growth and viability of the cells in a dose- and time-dependent manner. In addition, treatment of the MKN45 cells with a combination of the phenolic compounds extracts and cytarabine further decreased cell compared to monotherapy of the cells with each compound alone. Mechanistically, we showed that the anti-cancer effects of the olive polyphenols in the MKN45 cells are mediated through depletion of ROS. Similarly, polyphenolic extracts were found to decrease ROS level in the normal cells at
the concentrations of 500 and 1000 μg.mL-1and short treatment times (6 h), but the viability of these cells did not significantly change. At high concentrations (2000 μg.mL-1) of the phenolic extracts or at longer times of incubation (12 h), however, both
ROS levels and the viability of the cells were significantly decreased in the normal cells.
Conclusions: The olive fruits polyphenolic extract modulates ROS levels and selectively targets cancerous cells at low concentrations. Also, the effects of cytarabine could be potentiated by the olive fruits polyphenols. Thus, for a combined protocol of cancer cell therapy, olive fruit polyphenolic compound could be proposed as a proper candidate.
... The first group was the Tarom varieties (T) and consisted of nine Iranian olive varieties including T10, T15, T16, T17, T18, T20, T22, T23, and T24. The second group consisted of four Mediterranean varieties including Koroneiki and Arbequina, selected for the relatively high and low content of oleic acid in their oil, respectively (Parvini et al., 2015;Homapour et al., 2016); and Cornicabra and Picual, selected for their high phenolic contents (Gómez-Alonso et al., 2002;Beltrán et al., 2004). The third group consisted of three major varieties in Iran including Zard, Mari, and Rowghani. ...
Various nutraceutical properties of olives are ascribed to their different oil compositions and diversity of their active substances. Iran is endowed with great olive diversity which deserves to be studied. Accordingly, nine minor Iranian olive varieties, i.e. Tarom (T) varieties, were studied. Characterization of these minor varieties (T10, T15, T16, T17, T18, T20, T22, T23, T24) along with 3 major Iranian and 4 Mediterranean varieties with 11 chromosomal SSR markers revealed remarkable diversity among them. Most of T varieties had oil and Total Phenolic Content (TPC) comparable to Mediterranean olives. In comparison with Mediterranean varieties, T18 and T22 had higher Oleic Acid (OlA). T24 and T18 contained the highest and the lowest Linoleic Acid (LiA), respectively. T18 exhibited the highest OlA/LiA ratio. T24 was exceptionally phenols-rich variety followed by T20. Radical Scavenging Activities (RSA) results hardly suggested linear correlation between TPC and antioxidant capacity of the examined varieties. Nonetheless, T22 showed Phenol Antioxidant Coefficient higher than Mediterranean samples. Harvest time was influential on LiA content and the (RSA/TPC) ratios. Considering nutraceutical potential, some of T varieties are superior to the prevailing Iranian and Mediterranean varieties, so, they deserve to be introduced to olive improvement programs.
... The HPLC techniques are widely used both in the separation and in the quantification of phenolic compounds. Several mobile phases are available for analysis of anthocyanins, procyanidins, flavonones and flavonols, flavones and phenolic acids (Gómez-Alonso et al., 2002;Senter et al., 1989). Moreover, the introduction of reverse phase HPLC columns has enhanced considerably the separation of different classes of phenols (Manuel et al., 1990;Tarnawski et al., 2006). ...
Phenolic compounds are a large family of metabolites that result from the secondary metabolism of plants. Novel insights about phenolic chemical structure, analytical methods, therapeutic effects, sensory properties, viticultural practices to modify their content and the use of these compounds found in agro-industrial wastes have been gathered in this book. A comprehensive overview on phenolic compounds and neurodegenerative disorders, highlighting their antioxidant, anti-inflammatory properties and their effects on Parkinson’s disease have been compiled. In relation to antioxidant properties, the metabolism and bioavailability of several hydroxycinnamic acids present in coffee have been studied in detail, and also the methods to determine antioxidant capacity have been included. Different strategies in order to improve the extraction and determination of phenolic compounds in a complex matrix by analytical techniques are provided, reporting problems and new analytical solutions. The role of these compounds in color stabilization and also in bitterness and astringency perception has been reported. Moreover, the interactions that take place among no volatile and volatile compounds present in wine affecting sensory perception have been briefly introduced. Furthermore, the use of cover crops in vineyards and their effects on agronomical and enological behavior – particularly, their impact on phenolic compounds – have been highlighted. Finally, the biological properties of phenolic compounds from industrial wastes have been tackled, since they are a promising alternative to transform agro-industrial wastes into a source of natural and healthy compounds.
... To determine the content of total free and ester bound phenolics the Folin-Ciocalteu method was used [19]. To an aliquot of the extract, diluted Folin-Ciocalteu reagent was added. ...
The goal of this study was to evaluate the most effective technique for extraction of phenolics present in flax shives and to assess their effect on human fibroblasts. Flax shives are by-products of fibre separation, but they were found to be a rich source of phenolic compounds and thus might have application potential. It was found that the optimal procedure for extraction of phenolics was hydrolysis enhanced by the ultrasound with NaOH for 24 h at 65°C and subsequent extraction with ethyl acetate. The influence of the flax shives extract on fibroblast growth and viability was assessed using the MTT and SRB tests. Moreover, the influence of flax shives extract on the extracellular matrix remodelling process was verified. The 20% increase of the viability was observed upon flax shives extract treatment and the decrease of mRNA collagen genes, an increase of matrix metalloproteinase gene expression, and reduction in levels of interleukin 6, interleukin 10, and suppressor of cytokinin signaling 1 mRNA were observed. Alterations in MCP-1 mRNA levels were dependent on flax shives extract concentration. Thus, we suggested the possible application of flax shives extract in the wound healing process.
... These could be used as an index of the crushing conditions and of the fruit pulp/seed ratio during olive processing. (Gómez-Alonso, Desamparados Salvador, & Fregapane, 2002;Jolayemi, Tokatli, & Ozen, 2016;Owen et al., 2000). Recently, pinoresinol has also been proposed as a marker to authenticate from Picual (Cecchi et al., 2017). ...
... Indeed, as mentioned in this chapter, the average PV trend observed at 25 • C for VOO ( Until now, OO stability has commonly been evaluated by accelerated methods employing relatively high temperatures (100-120 • C) and an air flow (10-20 L/h) supply (e.g., Rancimat or the active oxygen method [AOM]) (Abaza et al., 2005;Aparicio et al., 1999;Baldioli et al., 1996;Koski et al., 2002;Mateos et al., 2003Mateos et al., , 2005. These rapid tests are very useful for practical purposes and give a good correlation with concentrations of phenolic compounds in OO (Gómez-Alonso et al., 2002;Gutfinger, 1981;Salvador et al., 2001), but OSI is not recognized as a legal parameter due to the unsatisfactory relationship between the results of these accelerated assays and the real shelf life of such food products (Frankel, 2005;Gómez-Alonso et al., 2007;Kaya et al., 1993;. This is probably because the oxidation mechanism is significantly different at temperatures above 60 • C; moreover, at higher temperatures, the oxidation reaction becomes more dependent on oxygen concentration because oxygen solubility decreases. ...
Lipid oxidation occurs slowly at room temperature; nevertheless, it is the main cause of quality deterioration of olive oil and determines its shelf life. The main components of olive oil are triacylglycerols, the unsaturated fatty acids of which are susceptible to autoxidation; however, it also contains minor compounds with antioxidant activities that provide resistance to oxidative degradation. This chapter discusses the influence and the behavior of olive oil natural antioxidants and minor functional components with regard to the oxidative stability and quality of the oil during storage and shelf life. After almost two years of storage, there were no detectable changes in oleic acid, the main fatty acid in OO. The changes observed in the polyunsaturated fatty acids (PUFAs), linoleic and linolenic acids, are higher as expected. Antioxidant activity has usually been measured by the effect of antioxidants in delaying the extent of oxidation.
... Where T and C are average mycelial growth in treatment and control respectively. Isolation of compounds using semi preparative HPLC The phenolic composition of B. napus was determined by HPLC (Knauer, Germany), a method described by Gomez-Alonso et al., (2002) with some modifications. Samples were filtered through a 0.45 μm membrane Millipore chromatographic filter before injection (injected volume, 50 L). ...
Some plant extracts have been reported to exhibit antimicrobial properties. Plant based pesticides appear to be an alternative for the synthetic pesticides because of their less dangerous impacts. The objective of this study was to assess the inhibitory activity of Brassica napus water extract on mycelial growth of six phytopathogenic fungi Rhizoctonia solani, Phythophtora drechseleri, Pythium aphanidermatum, Verticellium dahliae, Fusarium oxysporum, and Gaeumannomyces graminis. Antifungal activity test was performed by disc diffusion method. Concentrations of 100 and 50 ppm had the highest and the lowest inhibitory effects on all studied species respectively. The shoot extract (SE) was significantly exerted higher antifungal activity than root extract (RE). At 100 ppm, V. dahliae (17.02% inhibition by RE) and F. oxysporum (50% inhibition by SE) were the most sensitive species however, R. solani (1.8 and 15%) was the most resistant fungus to both extracts. Active compounds of B. napus extract were determined by high performance liquid chromatography (HPLC). Phenolic compounds had the highest concentrations in extracts and are probably the main cause of the mycelial growth inhibition. Application of canola aqueous extract or incorporation of canola in crop rotation program can be considered as a method for management of some soil-borne phytopathogenic fungi.
... Apart from the saponifiable fraction, composed mainly of triglycerides, with a low polyunsaturated fatty acid content, it contains a group of antioxidant molecules made up mainly of polyphenols and tocopherols ( Coetesi et al., 1995;tsimidou, 1998;esti et al., 1998;VelasCo and dobarGanes, 2002;laVelli and bondesan, 2005;bendini et al., 2007;siCari et al., 2009;siCari et al., 2010;Giuffrè et al., 2010). The polar phenolic molecules of virgin olive oil belong to different classes: phenolic acids, phenolic alcohols, lignans, secoiridoids and flavonoids (anGerosa and di GioVaCCHino, 1996;brenes et al., 1999;owen et al., 2000a;owen et al., 2000b;Gomez-alonzo et al., 2002;laVelli and bondesan, 2005). Of the antioxidant compounds, it is also important to consider the tocopherols. ...
In this study, the physicochemical properties and bioactive compounds of olive oils from cultivars "Roggianella", "Sinopolese" and "Ottobratica", grown in the province of Reggio Calabria (Italy) have been evaluated. Polyphenols are a large family of compounds found in fruits and vegetables, which exhibit strong antioxidant activity by scavenging different families of Reactive Oxygen Species (ROS). Dialdehydic form decarboxymethyl oleuropein aglycon, hydroxytyrosol acetate, dialdehydic form oleuropein aglycon, pinoresinol, 1-acetoxypinoresinol, tyrosol and vanillic acid were the main phenolic compounds in all samples analyzed. Pinoresinol was the most abundant compound in the lignin fraction. In all oil samples analyzed the highest antioxidant capacity was attributed to Roggianella oil (36.85% I of DPPH and 4.07% I of ABTS) compared to Ottobratica (27.37% I of DPPH and 2.52% I of ABTS) and Sinopolese (18.33% I of DPPH and 1.72% I of ABTS). The main characteristics of the Roggianella cultivar were a very high concentration of total phenols (530 mg/kg of gallic acid) and α-tocopherol (211 mg/kg).
... These compounds also present an important technological value due to their influence on sensory characteristics and virgin olive oil's shelf life (Lozano-Sánchez et al., 2012). Additionally, the concentration and composition of phenolic compounds in EVOO are strongly affected by many agronomical and technological factors such as the type of olive cultivar (Ammar, Zribi, Gargouri, Flamini, & Bouaziz, 2014), growing regions , climate, degree of maturation (Bouaziz, Chamkha, & Sayadi, 2004), crop season (Gómez-Alonso, Salvador, & Fregapane, 2002), irrigation and production process (Ammar et al., 2014). The prevalent classes of phenolic compounds found in EVOO are phenolic alcohols, phenolic acids, flavonoids, lignans and secoiridoids. ...
The aim of the present research is to evaluate the chemical characterization of main compounds from Tunisian monocultivar Extra virgin olive oil (EVOO) (‘Chemlali’, ‘Chétoui’, ‘Zalmati’ and ‘crossbreeding Chemlali by Zalmati’) extracted after the addition of different amounts (0% and 3%) of olive leaves. As expected for virgin olive oil, the main sterols found in all analyzed samples were β-sitosterol, ∆-5-avenasterol, campesterol and cholesterol. Stigmasterol, 24-methylene-cholesterol, clerosterol, campestanol, sitostanol, ∆-7-stigmastenol, ∆-5,24-stigmastadienol, and ∆-7-avenasterol were also found in all samples, but in lower amounts. Most of these compounds were significantly affected by the cultivars but not to be affected by added leaves at 3% to olives prior to the extraction process. The obtained results revealed that 14 phenolic compounds belonging to different phenolic types were characterized and quantified by an effective HPLC-DAD-ESI-MS/MS method. In all the studied olive-oil samples, dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA), oleuropein aglycon (3,4-DHPEA-EA), and ligstroside aglycon (p-HPEA-EA) were the most abundant compounds. In addition, EVOO from ‘Chétoui’ cultivar extracted with 3% of olive leaves presented the highest amount of individual phenolic compounds.
... Effect of temperature a more stable composition of fatty acids under such conditions, but also contains polyphenols which act by reacting rapidly with lipid radicals and are thereby consumed [34,35]. Peanut oil, with high oleic acid content showed a similar behaviour than EVOO. ...
Extra virgin olive oil shelf-life could be defined as the length of time under normal storage conditions within which no off-flavours or defects are developed and quality parameters such as peroxide value and specific absorbance are retained within accepted limits for this commercial category. Prediction of shelf-life is a desirable goal in the food industry. Even when extra virgin olive oil shelf-life should be one of the most important quality markers for extra virgin olive oil, it is not recognised as a legal parameter in most regulations and standards around the world. The proposed empirical formula to be evaluated in the present study is based on common quality tests with known and predictable result changes over time and influenced by different aspects of extra virgin olive oil with a meaningful influence over its shelf-life. The basic quality tests considered in the formula are Rancimat® or induction time (IND); 1,2-diacylglycerols (DAGs); pyropheophytin a (PPP); and free fatty acids (FFA). This paper reports research into the actual shelf-life of commercially packaged extra virgin olive oils versus the predicted shelf-life of those oils determined by analysing the expected deterioration curves for the three basic quality tests detailed above. Based on the proposed model, shelf-life is predicted by choosing the lowest predicted shelf-life of any of those three tests.
This study aimed to characterize mechanical properties of five pecan oils and one olive oil using a texture analyzer compared to a rotational viscometer; results were linked to fatty acid profile and total polyphenol content. The seven texture parameters (firmness, consistency, cohesiveness, viscosity index, stickiness at 5 sec, stickiness at 30 sec, and delta stickiness) showed significant difference (p≤0.05) among the six oils. Overall, olive oil had higher texture analysis values and significantly higher rotational viscosity than pecan oils. Chemically, C18 fatty acids accounted for approximately 90% of the total fatty acids in the five pecan oils. Olive oil had a higher amount of long‐chain, unsaturated fatty acids. Total polyphenols in pecan oils were 8‐15 mg gallic acid equivalent (GAE)/100 g, while olive oil contained 27.2 mg GAE/100 g. Correlation analysis demonstrated a significant, positive relationship between “consistency” texture and rotational viscosity measurement. Mechanical properties (seven texture parameters and rotational viscosity) were partially correlated to fatty acid profile, though no universal pattern was identified. Pecan is among the most commonly consumed tree nuts worldwide, while pecan oil is part of the emerging healthy, edible oil niche market. Few studies have investigated pecan oil sensory quality and associated physicochemical compositions for aroma, taste, and texture and pecan oil textural parameters have not been characterized. This study characterized pecan oil with seven textural parameters correlated to rotational viscosity and chemical composition, providing a novel instrumental approach to characterize edible oil textural properties. This article is protected by copyright. All rights reserved.
The production of extra virgin olive oil (EVOO) flavored with diverse spices, herbs, fruits, and vegetables or natural aromas is believed to provide advantageous properties considering either the high nutritional value or biological activity in addition to the flavoring and industrial aspects. The biological activities including antioxidant and antimicrobial properties of Tunisian EVOO obtained from “Chemlali” variety and mixed with chili pepper were investigated. Molecular analyses, including the detection of twelve olive-infecting viruses and Pseudomonas savastanoi pv savastanoi, were performed to ensure that the samples were obtained from healthy olive trees and EVOO quality was not affected. Quality parameters like free acidity, peroxide number, oxidative stability, and specific absorption at K232 nm and K270 nm were also investigated and no significant variation was revealed. The content of minor compounds such as chlorophylls, carotenoids, and total phenols showed minor changes. However, the profiles of the volatile compounds showed remarkable differences, which appeared to be the main factor for the observed variability in consumer acceptance. The results showed for the first time high quantities of polyphenols and ortho-diphenols. Four colorimetric methods were used for the determination of the antioxidant activity, namely DPPH, ABTS, FRAP, and β-carotene test. Compared to the control, a higher level of antioxidant activity was observed for the flavored EVOO. Furthermore, significant results were obtained in the antimicrobial tests. The quality parameters of the mixture showed no alteration compared to the control. Finally, all the measurements and the chemical characterization gave a scientific basis for food technology innovation of new food products.
Background: During the last decades, olive oil consumption has experienced a continuous
increase due to its unique organoleptic properties and its related beneficial properties.
Consequently, waste and by-products derived from the olive production have also increased causing environmental problems and economic losses. However, the low-cost and huge availability of these by-products is an opportunity for their valorization and the obtaining of high added-value compounds such as tyrosol, hydroxytyrosol (HT), oleocanthal, oleuropein (OLE), ligstroside, squalene, fatty acids, etc. The development of innovative extraction and characterization technologies is a key factor for the olive sector. In addition, a deeper knowledge about the biological properties of the compounds present in the recovered products and their mechanism of action is crucial to allow their integration in the food chain and their potential uses in the food and pharmaceutical industries. Scope and approach: This review encompasses all these aspects showing the advances achieved to date in the olive oil by-products valorization focusing on their biological properties, including cardioprotective, antioxidant, anticancer, antiinflammatory and antidiabetic effects. Key findings and conclusions: The by-products derived
from the Olea europaea L. processing industry are secondary but valuable products, from which different biologically active molecules can be recovered by green extraction technologies (PLE, SFE, etc.) and reused for food, pharmaceutical and cosmetic purposes following the circular economy policies. One of the main advantages on recovering valuable molecules from olive by products is their incorporation to functional foods. A direct effect was proved between the use of olive by-products in human consumption and the heath claims. In this context, different food industries have used the phenolic fraction of olive by-products, holding mostly HT and OLE, as food additives and as preserving agents due to their antioxidant properties.
Kiwifruit hold significant nutritional value and are a good source of antioxidants due to their diverse range of bioactive compounds. Kiwifruit waste is generated throughout the food supply chain, particularly during transportation and storage. Kiwifruit rejected from the retail market due to unfavorable appearance still possess potential economic value as kiwifruit are abundant in phenolic compounds. The present work studied the phenolic profile and antioxidant potential of rejected kiwifruit, including SunGold (Actinidia chinensis), Hayward (Actinidia deliciosa), and round organic Hayward (Actinidia deliciosa). Regarding phenolics estimation, SunGold possessed the highest TPC (0.72 ± 0.01 mg GAE/g), while Hayward exhibited the highest TFC (0.05 ± 0.09 mg QE/g). In antioxidant assays, SunGold showed the highest antioxidant activities in DPPH (0.31 ± 0.35 mg AAE/g), FRAP (0.48 ± 0.04 mg AAE/g), ABTS (0.69 ± 0.07 mg AAE/g), •OH-RSA (0.07 ± 0.03 mg AAE/g) assays, and FICA (0.19 ± 0.07 mg EDTA/g), whereas Hayward showed the highest RPA (0.09 ± 0.02 mg AAE/g) and TAC (0.57 ± 0.04 mg AAE/g). Separation and characterization of phenolics were conducted using LC-ESI-QTOF-MS/MS. A total of 97 phenolics were tentatively characterized from rejected SunGold (71 phenolics), Hayward (55 phenolics), and round organic Hayward (9 phenolics). Hydroxycinnamic acids and flavonols were the most common phenolics characterized in the three samples. The quantitative analysis was conducted by HPLC-PDA and found that chlorogenic acid (23.98 ± 0.95 mg/g), catechin (23.24 ± 1.16 mg/g), and quercetin (24.59 ± 1.23 mg/g) were the most abundant phenolics present in the rejected kiwifruit samples. The notable presence of phenolic compounds and their corresponding antioxidant capacities indicate the potential value of rescuing rejected kiwifruit for further utilization and commercial exploitation.
Cancer is among the leading causes of mortality worldwide. Current cancer therapies are associated with serious side effects, which further damage patients' health. Therefore, the search for new anticancer agents with no toxic effects on normal and healthy cells is of great interest. Recently, we and other groups have demonstrated that oleocanthal (OLC), a phenolic compound from extra virgin olive oil, exhibits antitumor activity in various tumor models. However, the underlying mechanisms and intracellular targets of OLC remain to be completely elucidated. This review summarizes the current advancers concerning the anticancer activity of OLC, with particular emphasis on the molecular signaling pathways modulated by this compound in different tumor cell types. The major mechanisms of action of OLC include modulation of the apoptotic pathway, the HGF/c‐Met pathway, and the signal transducer and activator of transcription 3 signaling pathway, among others. Furthermore, OLC has synergistic effects with anticancer drugs in vitro. Also discussed are OLC bioavailability and its concentration in olive oil. Data summarized here will represent a database for more extensive studies aimed at providing information on molecular mechanisms against cancer induced by OLC.
This study was aimed at determining if oxidative stress imbalance in testes of rats occurs after n-butylparaben (n-ButP) exposure. Young male Sprague-Dawley rats were subcutaneously treated with n-ButP during one spermatogenic cycle (57 days) at 0 (control-oil), 150, 300 and 600 mg/kg/d with peanut oil as vehicle. A non-vehicle control group was also included. Antioxidant enzyme activities (superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase) and levels of reduced and oxidized glutathione were measured in testes. Lipid peroxidation and H2O2 concentrations were also assessed. Results showed an increase of oxidative stress in oil-treated groups, excepting 600 mg/kg/d, suggesting oxidative stress due to peanut oil. A possible antioxidant effect due to n-ButP and its metabolites was suggested at 600 mg/kg/d, the only group not showing oxidative stress. An increase of calcium concentration in testes was also observed. On the other hand, a physiologically-based pharmacokinetic (PBPK) model was developed and the concentrations of n-ButP and its metabolites were simulated in plasma and testes. The peak concentration (Cmax) in testes was found slightly higher than that in plasma. The current results indicate that peanut oil can cause oxidative stress while high doses of n-ButP can act as antioxidant agent in testes.
The chemical and sensory characteristics of the extra virgin olive oils (EVOO) produced in the Spanish regions of Castilla‐La Mancha and Extremadura according to the protected designation of origin (PDO) quality scheme of the European Union are reviewed. This zone is the second in importance in Spain after the southern region of Andalusia. A total PDO olive trees cultivated surface of 694,800 ha, almost one third of the total, and some 380 related oil mills are currently registered in Spain. Cornicabra and Picual EVOOs ‐ related to Montes de Toledo, Campo de Montiel and Calatrava PDOs ‐ are those with the highest intensity of bitterness and pungency, sensory attributes directly related to their higher content in phenolic compounds (556 ± 214 mg/kg and 605 ± 180 mg/kg, respectively). On the contrary, Manzanilla cacereña and Cornezuelo oils ‐ associated with Gata‐Hurdes and Aceites Monterrubio PDOs ‐ show a lower score in these two positive attributes. Differences in the fatty acid profile and in certain sterols and triterpenic alcohols (mainly total content, campesterol, Δ5‐Avenasterol, stigmasterol and erythrodiol and uvaol) may be useful, not without difficulties and in combination with other families of chemical compounds (e.g. individual phenolics and volatiles) to discriminate between olive oils obtained from different varieties or geographical areas.
Practical Applications: It is relevant to gather and compare the chemical and sensory characteristics of the PDO EVOOs produced in central Iberian Peninsula, the second main zone of economic importance in Spain. Indeed, providing clear information on olive oils linked to geographical origin is of interest to farmers and producers and furthermore enable consumers to make more informed purchasing choices. A critical review on published data is also useful to focus the design of future studies needed for achieving the full characterization of these EVOOs.
The aim of this work was to evidence the quality of four monovarietal olive oils (Carolea, Grossa di Gerace, Ottobratica, and Sinopolese cv) produced at two crop years and at different harvesting times in Calabria region, located in the South of Italy. Qualitative parameters of oils were evaluated by analysis of major and minor components, in particular: free acidity, peroxide value, fatty acid composition, sterol composition, total polar phenolic compounds and tocopherols, and total pigments. The total antioxidant activity of olive oils was evaluated by DPPH and ABTS assays. Two variables were evaluated in the statistical data elaboration: the cultivar and the harvesting time. Their effect was studied on the chemical parameters and antioxidant components. The harvesting at October and November did not reduce the quality of two monovarietal olive oils (Carolea and Sinopolese) produced in Calabria, whereas Ottobratica and Grossa di Gerace olive oils produced at November had a lower quality. However a reduction of qualitative parameters was observed in extra virgin olive oils produced from lately harvested olives with some differences among cultivars.
Practical applications: Practical application for the study entitled ‘Effect of the harvesting time on the quality of olive oils produced in Calabria’ regards the study of chemical composition on olive oils produced under a controlled experimental procedure. Varietal characteristics and environmental variables affect in general the quality of the olive productions and the obtained olive oils. The results of this work showed that the considered harvesting times did not involve a decay of quality on Carolea and Sinopolese olive oils produced in the South of Italy, obtained following right processing procedures.
Many phenolics occurring in olives are also present in the by-products, particularly in seeds, produced during olive oil processing. We investigated the effect of the treatment of olive fruits with abscisic acid on phenolics in olive seeds as compared with pulps. Effect of the storage time is also considered. The results showed that the treatment resulted in higher total phenolic content, scavenging free radical activity and oleuropein and hydroxytyrosol contents than those untreated. The effect of abscisic acid was more pronounced in pulps than in seeds and depended on the storage time. Seeds from treated olives reached values of oleuropein and hydroxytyrosol of 666 and 987 mg kg⁻¹ which were similar to those obtained in the pulps (ie, 607 and 512 mg kg⁻¹). Since seeds are a residue from oil processing, abscisic acid treatment is proposed a promising technique to obtain enriched olives and simultaneously a high added value by-product.
Ethanol was used to induce acute hepatotoxicity in mice. Effects of cinnamic acid (CA) and syringic acid (SA) post-intake for hepatic recovery from alcoholic injury was investigated. Ethanol treated mice were supplied by CA or SA at 40 or 80 mg/kg BW/day for 5 days. Results showed that ethanol stimulated protein expression of CYP2E1, p47phox, gp91phox, cyclooxygenase-2 and nuclear factor kappa B in liver. CA or SA post-intake restricted hepatic expression of these molecules. Ethanol suppressed nuclear factor erythroid 2-related factor (Nrf2) expression, and CA or SA enhanced Nrf2 expression in cytosolic and nuclear fractions. Ethanol increased the release of reactive oxygen species, oxidized glutathione, interleukin-6, tumor necrosis factor-alpha, nitric acid and prostaglandin E2. CA or SA lowered hepatic production of these oxidative and inflammatory factors. Histological data revealed that ethanol administration caused obvious foci of inflammatory cell infiltration, and CA or SA post-intake improved hepatic inflammatory infiltration. These findings support that cinnamic acid and syringic acid are potent nutraceutical agents for acute alcoholic liver disease therapy. However, potential additive or synergistic benefits of cinnamic and syringic acids against ethanol-induced hepatotoxicity need to be investigated.
The purpose of this study was to evaluate and compare the effects of early (EHVOO) and late harvest (LHVOO) dates on phenolic composition of virgin olive oils (VOO) from the Ayvalik (Edremit) variety. Liquid chromatography combined with a diode array detector and ion spray mass spectrometry in the tandem mode (LC-DAD-ESI-MS/MS) with negative ion detections was used for identification of phenolic compounds in the VOOs. A total of 14 phenolic compounds were identified and quantified in VOOs, including phenolic alcohols (2), phenolic acids (4), secoiridoids (5), and flavonoids (3). Secoiridoids followed by phenolic alcohols and flavonoids were the most abundant compounds of the VOOs. Among secoiridoids 3.4-DHPEA-EDA and 3.4-DHPEA-EA were the most dominant compounds. The antioxidant capacity of VOOs was determined by two different methods, including DPPH and ABTS. The antioxidant capacity of LHVOO was found to be higher than that of EHVOO. Additionally, significant linear correlation was confirmed between the phenolic content and antioxidant capacities of VOOs.
The total polar fraction and individual phenols present in virgin olive oil were tested for their antioxidant effect in refined
olive oil. Hydroxytyrosol and caffeic acid showed protection factors greater than BHT. Protocatechuic and syringic acid were
also found to have antioxidant activity. Tyrosol, p-hydroxyphenylacetic acid, o-coumaric acid, p-coumaric acid, p-hydroxybenzoic
acid and vanillic acid had very little or no effect, and their contribution to the stability of the oil is negligible.
Polyphenols of olive oil show autoprotective, sensory, and nutritional-therapeutic effects. Two new phenolic compounds have
been isolated from virgin olive oils by preparative high-performance liquid chromatography and their structures established
on the basis of their mass spectra and nuclear magnetic resonance spectral data. The compounds identified are the lignans
pinoresinol and 1-acetoxypinoresinol. Both have been found in all the commercial virgin olive oils analyzed. Pinoresinol concentration
was rather similar in all the oils. In contrast, 1-acetoxypinoresinol concentration was higher in oils of the Arbequina and
Empeltre cultivars than in Picual or Picudo cultivars. Pinoresinol and 1-acetoxypinoresinol may represent the major phenolic
compounds in some Arbequina and Empeltre oils. Lignans possess biological and pharmacological properties and, therefore, the
two new compounds identified in olive oils may contribute to the reported beneficial effects which are attributed to polyphenols
on human health of a diet rich in olive oil.
Phenolic compounds are of fundamental importance to the shelf life of virgin olive oils because of their antioxidative properties.
In this paper, the evolution of simple and complex olive oil phenols during 18 mon of storage is studied by high-performance
liquid chromatography (HPLC) analysis. The olive oils under examination were from various olive cultivars, harvested in two
sectors in the same region at different stages of ripeness. The findings indicate that it is not the variety but rather the
ripeness of the olives and the soil and climate that influence the phenol composition of virgin olive oil. In addition, a
positive correlation was found between the age of the oils and the tyrosol to total phenols ratio. Lastly, gas chromatography-mass
spectrometry analysis confirmed that the unidentified peaks detected by HPLC were of a phenolic nature.
Phenolic compounds are of fundamental importance to the quality and nutritional properties of virgin olive oils. In this paper,
the high-performance liquid chromatographic analysis of simple and complex olive oil phenols in the streams generated in the
two-phase extraction system was carried out using Arbequina and Picual olives. The malaxation stage reduced the concentration
of orthodiphenols in oil ca 50–70%, while the concentration of the nonorthodiphenols remained constant, particularly the recently identified lignans
1-acetoxypinoresinol and pinoresinol. Oxidation of orthodiphenols at laboratory scale was avoided by malaxing the paste under
a nitrogen atmosphere. Phenolic compounds in the wash water used in the vertical centrifuge were also identified. Hydroxytyrosol,
tyrosol, the dialdehydic form of elenolic acid linked to hydroxytyrosol were the most representative phenols in these waters.
Hence, phenolic compounds in the wash waters came from both the aqueous and the lipid phases of the decanter oily must.
Polyphenols influence the oxidative stability and sensory quality of virgin olive oil, Studies from the last 30 years are reviewed and the most significant findings are presented. Information is given on the main phenolic compounds detected and identified in olive fruit and oil. In recent years powerful analytical techniques (GC-MS, HPLC-MS, NMR) have been used to investigate the complex nature of olive oil polyphenols, Tyrosol, hydroxytyrosol, oleuropein aglycon and their derivatives with a non-phenolic acid and elenolic acid in free or esterified forms are the main components of the water-methanol extract of virgin olive oil, known as the polar fraction. Total phenol content as determined colorimetrically correlates well with the oxidative stability of the oil. The contribution of individual phenols to oil stability has not been fully investigated. There is still more to be known about the importance of the presence of phenolic components to the sensory quality of the oil.
In the present study the modification of detoxified and completely refined karanja oil (Pongamia glabra) was studied by physical and chemical means. Karanja oil was fractionated by the detergent fractionation process at low temperature (3 °C). Astearin fraction was obtained with a yield of 11.0 %. The stearin fraction as such or after bioacidolysis, was found to be suitable as margarine fat bases. Karanja oil was also blended with fats like palm stearin, vanaspati, hydrogenated rice bran oil, and hydrogenated soybean oil in various proportions. The blended products as such or after interesterification were found to be suitable as shortenings, margarine fat bases, or vanaspati substitute.
Modifizierung von Karanjaöl (Pongamia glabra) durch Fraktionieren, Mischen und Umestern.In der vorliegenden Studie wurde die Modifizierung von entgiftetem und vollständig raffiniertem Karanjaöl mittels physikalischer und chemischer Methoden untersucht. Karanjaöl wurde mit dem Tensid-Fraktionierungsverfahren bei niedrigen Temperaturen (3 °C) fraktioniert. Es wurde eine Stearinfraktion mit einer Ausbeute von 11,0% erhalten. Die unbehandelte Stearinfraktion und die nach Säurehydrolyse stellte sich als geeignete Fettgrundlage für Margarine heraus. Karanjaöl wurde außerdem mit Fetten, wie Palmölstearin, Vanaspati, hydrogeniertem Reiskleieöl und hydrogeniertem Sojaöl verschiedener Mengen gemischt. Die gemischten Öle und die zwischenveresterten Ölgemische stellten sich als geeignet für Backmischungen, Fettgrundlagen für Margarine oder als Ersatz für Vanaspati heraus.
The effect of extraction systems on the phenolic composition of virgin olive oils obtained from two different Italian cultivars (Coratina and Oliarola) was determined. The oils extracted using two-phase centrifugation showed in all cases higher phenolic concentration in comparison to oils obtained from three-phase centrifugation. In particular, the highest differences were observed for aglykone derivatives of oleuropein (3,4-DHPEA-EDA and 3,4-DHPEA-EA) that are the most concentrated antioxidant phenolic compounds of virgin olive oil. These results were confirmed by the autoxidation stability of the oils examined.Über die Auswirkung von Gewinnungsverfahren auf die Phenolzusammensetzung in unbehandeltem Olivenöl.Die Auswirkung von unterschiedlichen Extraktionssystemen auf die Phenolzusammensetzung in unbehandelten Olivenölen aus zwei verschiedenen italienischen Olivensorten (Coratina und Oliarola) wurde bestimmt. Öle, die mit dem Zweiphasen-Dekanter erzeugt wurden, zeigten in jedem Falle eine höhere Phenolkonzentration als Öle, die mit dem Dreiphasen-Dekanter gewonnen wurden. Insbesondere wurden höchste Unterschiede bei den Aglykonderivaten von Oleuropein (3,4-DHPEA-EDA und 3,4-DHPEA-EA) festgestellt, den am stärksten konzentrierten antioxidierenden Phenolverbindungen im unbehandelten Olivenöl. Diese Ergebnisse wurden durch die Stabilität der geprüften Öle gegen Autoxidation bestätigt.
Olive oil phenolic and secoiridoid compound derivatives were detected by mass spectrometry. Chemical ionization (CI) allowed us to obtain parent ions, that were not detectable in the electron impact mode. CI experiments were performed using either CH4 or NH3 as the reactant gas. Unlike CH4-CI, which fails to give molecular mass information, NH3-CI provided, in all the cases explored, an adduct ion [M+18]+ that was sufficiently stable to be detected and recorded. Information about molecular masses was very useful for the complete characterization of aglycons from glycosides occurring in virgin olive oils. Aglycons of ligstroside, of decarbomethoxyoleuropein and of oleuropein were detected. Each aglycon, because of several tautomeric equilibria involving the ring opening of secoiridoid, showed up as compounds with four main structures after derivatization with bis(trimethylsilyl)trifluoracetamide.
This review examines the composition of Cornicabra virgin olive oil, some of the factors that may affect it, like fruit ripening and extraction system, and their relation with quality. The main characteristics of Cornicabra oil were: high oleic acid (80.4 ± 1.0.%, as mean and standard deviation) and low linoleic acid content (4.5 ± 0.6%); high campesterol level (4.2 ± 0.2%), exceeding the EU Regulation upper limit of 4%; large total phenols content (ranging from 20 to 380 mg/kg as caffeic acid), and great Rancimat oxidative stability (from 10 to 140 h). Sensory evaluation showed that the total score of 35% of Cornicabra olive oils was lower than the limit of 6.5 established for the 'extra-virgin' category. The majority of the analytical parameters, i.e. peroxide value, K270, pigments, sensory scores, oleic acid and total sterols, diminished during ripening, whereas free acidity, linoleic acid and ∆-5- avenasterol increased. The behavior of oil extraction yield, oxidative stability, natural antioxidants and campesterol was more complex. The evolution of the analytical parameters studied suggests that the best stage of maturity of Cornicabra olive fruits for processing is a ripeness index higher than 3.0 and lower than 4.0-4.5. With respect to extraction system and crop season, only minor differences, although some of them statistically significant, were observed in the quality indexes of the Cornicabra virgin olive oil.
Phenolic compounds, which are present in significant amounts in virgin olive oil, are almost completely destroyed during the refining process of the oils. Numerous phenolic acids were found in oil samples and caffeic, p-coumaric, syringic, vanillic, ferulic, protocatechuic and p-hydroxybenzoic acids have been identified. Among these, p-coumaric acid was predominant in all virgin olive oil samples. They can play important roles as antioxidants and influence the flavour of the oil.
Phenolic compounds are important in relation to nutritional and sensory characteristics and the shelflife of virgin olive oil. Four new phenolic compounds have been separated by HPLC. The compounds are two (3,4-dihydroxyphenyl)ethanol derivatives and two (p-hydroxyphenyl)ethanol derivatives. This paper reports the NMR, IR, and UV characterization of three of these phenolic compounds. The compounds identified are an isomer of oleuropeine aglycon, the dialdehydic form of elenolic acid linked to (3,4-dihydroxyphenyl)ethanol, and the dialdehydic form of elenolic acid linked to (p-hydroxyphenyl)-ethanol.
This paper reports the preliminary characterization of unknown phenolic compounds in virgin olive oil, separated by HPLC using hydrolytic, chromatographic, and spectrophotometric techniques. It was possible to characterize oleuropeine aglycon and three hydrolyzable phenols containing (3,4-dihydroxyphenyl)ethanol or (p-hydroxyphenyl)ethanol.
Phenolic compounds have a fundamental importance in the nutritional and sensory characteristics of virgin olive oil. Problems regarding their qualitative and quantitative evaluation have not been completely solved; hence, in this paper the extractive and HPLC methods of analysis are examined and some modifications are presented. By means of these techniques, elenolic acid and four unknown compounds having phenolic behavior were separated from virgin olive oil. Four of them were correlated with total phenols evaluated by means of the Folin-Ciocalteu reagent, and two of them were correlated with olive oil autoxidation stability.
Sensory green attribute intensities, the total amount of complex phenolic compounds and the composition of volatile compounds from lipoxygenase pathways were measured in oils obtained from both industrial centrifugation plants and different kinds of laboratory mill. These data were evaluated by hierarchical cluster analysis, principal component analysis and linear discriminant analysis with the aim of distinguishing oil samples in relation to the extraction methodology. The statistical tests showed that the mentioned variables were able to differentiate oils according to the method adopted for their extraction from olive pastes. Oils from laboratory mills were clearly different from samples extracted industrially. This implies that results derived from investigations carried out using oils obtained from laboratory mills cannot be immediately transferred to oils from industrial plants. Oils from dual-phase decanters in industrial plants were more similar to samples extracted in conventional tri-phase industrial plants, even if they were all well differentiated according to the oil extraction methodology.© 2000 Society of Chemical Industry
An experimental investigation was carried out on olive oils of the Ogliarola Salentina and Coratina cultivars to assess the influence of the two different olive grinding techniques and kneading process on the quality of the oils. The experimental data obtained showed that resistance to oxidation, total phenols and phenolic compounds analysed for HPLC were higher in the Coratina oils than in the Ogliarola oils. The use of hammer-crushers plus kneader rather than stone mills plus kneader always produced significant increases in the total phenols. Resistance to oxidation was assessed by the Rancimat method and showed a significant correlation with the amounts of total phenols and of an unidentified substance (peak I) which was conspicuously present amongst the substances evaluated for HPLC.
The levels of total polyphenols and o-diphenols were determined in virgin oils and in chloroform/methanol-extracted oils.
The solventextracted oils were richer in polyphenols than the virgin oils. High polyphenol content was associated with a high
resistance to oxidation of the oils. A linear relationship was found between polyphenol content and the oxidative stability
of the virgin oils during storage at 60 C. After removal of the polyphenols, the oxidative stability of the oils decreased
considerably and seemed to depend on polyunsaturated fatty acid concentration.
The chemical composition of commercial Cornicabra virgin olive oils (n=65) was studied, as was its relationship with oil quality and the influence of the extraction method and production year.
The main characteristics of these olive oils were: oxidative stability 53 ± 24 h, mean polyphenol content 162 ± 57 mg/kg (as
gallic acid), oleic acid 80.8 ± 0.9%, linoleic acid 4.6 ± 0.6%, and campesterol 4.3 ± 0.1%, which is peculiar to this variety.
No clear differences in composition were observed with respect to the different extraction systems (dual-phase/triple-phase
decanters and pressure), although oils produced by the dual-phase decanter showed higher oxidative stability and polyphenol
content. There were significant differences in major fatty acids and sterols according to the production year.
A reverse-phase high-performance liquid chromatographic technique with isocratic elution has been developed to separate and
quantitate the major phenolic compounds of the hydroalcoholic extracts of olive oils. Hydroxytyrosol, tyrosol, caffeic acid,p-hydroxyphenylacetic acid and homovanillic acid were analyzed on a μBonapak C18 column with an acetonitrile/water/acetic acid
(20:90:0.18, vol/vol/vol) mixture as a mobile phase. Electrochemical detection provided selectivity as well as sensitivity.
The method was applied to the analysis of the most important phenolic compounds in olive oils.
The antioxidant effects of hydrophilic phenols and tocopherols on the oxidative stability in virgin olive oils and in purified
olive oil have been evaluated. Total hydrophilic phenols and the oleosidic forms of 3,4-dihydroxyphenolethanol (3,4-DHPEA)
were correlated (r=0.97) with the oxidative stability of virgin olive oil. On the contrary, tocopherols showed low correlation (r=0.05). Purified olive oil with the dialdehydic form of elenolic acid linked to 3,4-DHPEA, an isomer of oleuropeine aglycon,
and 3,4-DHPEA had good oxidative stability. A synergistic effect was observed in the mixture of 3,4-DHPEA and its oleosidic
forms with α-tocopherol in purified olive oil by the Rancimat method at 120°C.
Oxidation is the primary cause of virgin olive oil quality deterioration. This paper presents a correlation between oxidative
stability, as determined by the Rancimat method, and some chemical components involved in the oxidation process of a set of
74 Cornicabra virgin olive oils obtained from three successive crop seasons (94/95 to 96/97). Results showed a clear influence
of total polyphenols on virgin olive oil stability, with linear regression coefficients which were similar for the three seasons
studied, and a much lower contribution of α-tocopherol and unsaturated fatty acids, mainly linoleic acid. A significant effect
dependent on the crop season was also observed.
The stability of 24 samples of Greek virgin olive oil was examined in relation to total polyphenol content, and individual phenols were determined by reversed-phase HPLC. Tyrosol, the major olive-oil phenol, is not correlated with the shelf-life of the oil. Total polyphenol content and hydroxytyrosol-to-tyrosol ratio have a significant linear correlation with the resistance of the oil to autoxidation.
The chemical composition of Cornicabra virgin olive oils (n=181) from five successive crop seasons (from 1994/95 to 1998/99) and its relationship with quality and oxidative stability is examined. The main characteristics of Cornicabra olive oils were: a high oleic acid (80.4±1.0%, as mean and standard deviation) and low linoleic acid content (4.5±0.6%); high campesterol level (4.2±0.2%), exceeding the EU Regulation upper limit of 4%; large total phenol content (ranging from 19 to 380 mg/kg as caffeic acid for the commercial oils, and from 180 to 614 mg/kg for the Abencor oils), and oxidative stability ranging from 9 to 143 h, by Rancimat, for the commercial oils and from 18 to 193 h for the Abencor oils. Sensory evaluation showed that the total score of 35% of commercial Cornicabra olive oil was lower than the limit of 6.5 established for the ‘extra-virgin’ category, whereas the minimum score observed for Abencor oils was 6.8. This means that, although the majority of the chemical parameters fell within the limits established for the maximum olive oil category, with a few exceptions, significantly more of these olive oils fail the sensory minimum requirements for the highest category.
The effect of the use of cell-wall-degrading-enzyme preparations during the mechanical extraction process of virgin olive oil on the phenolic compounds and polysaccharides was investigated. The use of the enzyme preparations increased the concentration of phenolic compounds in the paste, oil, and byproducts Especially, the contents of secoiridiod derivatives such as the dialdehydic form of elenolic acid linked to 3,4-dihydroxyphenylethanol (3,4-DHPEA-EDA) and an isomer of oleuropein aglycon (3,4-DHPEA-EA), which have high antioxidant activities, increased significantly in the olive oil. Furthermore,the use of an N-2 flush during processing strongly increased the phenolic concentration. Analyses of the pectic polymers present in the paste showed that the use of pectinolytic enzyme preparations increased the yield of the buffer soluble pectins and the proportion of molecules with a lower molecular mass; Also, the content of uronic acids in the buffer soluble extract increased considerably due to the use of the enzyme preparations. Analysis of the polymeric carbohydrates in the vegetation waters showed the presence of mainly pectic polymers. The addition of commercial enzyme preparations increased the uronic acid content of the polysaccharides in the vegetation, water substantially compared to the blank. This study showed that the addition of cell-small-degrading enzymes did improve the olive oil quality; however, mechanisms remained unclear.
Phenolic compounds in Spanish virgin olive oils were characterized by HPLC. Simple phenols such as hydroxytyrosol, tyrosol, vanillic acid, p-coumaric acid, ferulic acid, and vanillin were found in most of the oils. The flavonoids apigenin and luteolin were also found in most of the oils. The dialdehydic form of elenolic acid linked to tyrosol and hydroxytyrosol was also detected, as were oleuropein and ligstroside aglycons. The structure of a new compound was elucidated by MS and NMR as being that of 4-(acetoxyethyl)-1,2-dihydroxybenzene. Changes of phenolic compounds in virgin olive oils with maturation of fruits were also studied. Hydroxytyrosol, tyrosol, and luteolin increased their concentration in oils with maturation of fruits. On the contrary, glucoside aglycons diminished their concentration with maturation. No clear tendency was observed for the rest of the phenolic compounds identified.
Because olive oil is an important component of the Mediterranean diet, it is necessary to establish unequivocal identification of the major potential antioxidant phenolic compounds it contains.
The major phenolic antioxidants in extra virgin olive oil were isolated and purified. Structural analysis was conducted using several spectroscopic techniques, including mass spectrometry and nuclear magnetic resonance (NMR). In particular, detailed (1)H and (13)C NMR data are presented, and several assignment errors in the literature are corrected.
The data show for the first time that the lignans (+)-1-acetoxypinoresinol and (+)-pinoresinol are major components of the phenolic fraction of olive oils. These lignans, which are potent antioxidants, are absent in seed oils and virtually absent in refined virgin oils but are present at concentrations of up to 100 mg/kg (mean +/- SE, 41.53+/-3.93 mg/kg; range, 0.65-99.97 mg/kg) in extra virgin oils. As with the simple phenols and secoiridoids, there is considerable interoil variation in lignan concentrations. Foods containing high amounts of lignan precursors have been found to be protective against breast, colon, and prostate cancer.
Lignans, as natural components of the diet, may be important modulators of cancer chemopreventive activity.
A simple analytical method for the quantitative determination of phenols, flavones, and lignans in virgin olive oils was developed. The polar fraction was isolated from small amounts of oil sample (2.5 g) by solid-phase extraction (SPE) using diol-phase cartridges, and the extract was analyzed by reversed-phase HPLC coupled with diode array UV detection. Chromatographic separation of pinoresinol, cinnamic acid, and 1-acetoxypinoresinol was achieved. Repeatability (RSD < 6.5%), recovery (> 90%), and response factors for each identified component were determined. SPE on amino-phase cartridges was used for isolating acidic phenols and as an aid for phenol identification. For the first time, 2-(4-hydroxyphenyl)ethyl acetate was detected in olive oils. The aldehydic structure of the ligstroside aglycon was confirmed by NMR spectroscopy. The colorimetric determination of total o-diphenolic compounds by reaction with molybdate was consistent with their HPLC determination. Differences between results obtained by liquid-liquid extraction and SPE were not statistically significant.
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