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Spain dominates avocado production in Europe, with the Hass variety being the most prominent. Despite this, Spanish production satisfies less than 10% of the overall avocado demand in Europe. Consequently, the European avocado market heavily relies on imports from overseas, primarily sourced from Peru and Chile. Herein, a comprehensive characterization of the metabolic profile of Hass avocado fruits from Spain, Peru, and Chile, available in the European market throughout the year, was carried out. The determination of relevant substances was performed using high- and low-resolution RP-LC-MS. Remarkable quantitative differences regarding phenolic compounds, amino acids, and nucleosides were observed. Principal component analysis revealed a natural clustering of avocados according to geographical origin. Moreover, a specific metabolic pattern was established for each avocado-producing country using supervised partial least squares discriminant analysis. Spanish fruits exhibited high levels of coumaric acid malonyl-hexose II, coumaric acid hexose II, and ferulic acid hexose II, together with considerably low levels of pantothenic acid and uridine. Chilean avocado fruits presented high concentrations of abscisic acid, uridine, ferulic acid, succinic acid, and tryptophan. Fruits from Peru showed high concentrations of dihydroxybenzoic acid hexose, alongside very low levels of p-coumaric acid, ferulic acid, coumaric acid malonyl-hexose I, and ferulic acid hexose II.

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The storage conditions are very critical to minimize hydrolytic and oxidative reactions of virgin olive oils (VOOs). These reactions are logically influenced by the composition of the VOO, so that each variety may have a specific behavior. The aim of this study was to evaluate changes in quality parameters and in the phenolic and triterpenic profile of Arauco VOOs, a unique local variety from Argentina, after storage under different conditions. The effects of exposure to light (darkness and light), temperature (24 and 40 °C), packaging material (polyethylene (PET) and dark glass), and headspace (air and N2 atmosphere) were investigated for 76 days. A reduction in total phenolic compounds was observed after storage treatments, but all samples still complied with the EFSA health claim after the different handlings. Overall, the results revealed that the preservation of the oils in PET appears adequate, with improved stability when N2 was used in the headspace, along with darkness and low temperature. The study of phenolic profiles showed that substances previously reported as possible markers of olive oil aging, such as hydroxytyrosol and an isomer of decarboxymethyl oleuropein aglycone, also have a similar behavior during the aging of Arauco variety oil. Interestingly, some evidence was found that another oleuropein-derived compound (oleuropein aglycone isomer 3) could also be used as an aging marker.

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BACKGROUND: The aim of this work was to evaluate and compare oil production and its quality in three Spanish olive varieties (Genovesa, Villalonga, and Nevadillo blanco) growing outside the Mediterranean basin with the Argentine autochthonous variety (Arauco). Fruit parameters and oil characteristics were evaluated using samples collected from the germplasm collection of Mendoza province and elaborated in the same place. RESULTS: The levels of phenolic compounds and the fatty acid composition of the samples were comparable with those previously published for these Spanish varieties, grown in the Mediterranean basin, showing the adaptability of olive trees. Observing the levels of phenolic compounds and oxidative stability, a strong correlation between oxidative stability and oleocanthal was observed. CONCLUSION: The characteristics of the fruit and oil differed according to variety and season. The inter-harvest stability was different depending on the variety. Genovesa was observed to be the most stable variety according to its fruit and oil characteristics - even more stable than the autochthonous variety, Arauco. However, in terms of the composition of phenolic compounds, Arauco was the most stable between harvests, this characteristic being more important for the taste and uniformity of the product. © 2020 Society of Chemical Industry.

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An important portion of vitamins, minerals and polyphenols components in human diet are captured from fruit consumption. Argentinean Patagonia Berberis microphylla was characterized with the phenolic content, the proximate composition and the identification and quantification of anthocyanins, not-anthocyanins and proteins. The antioxidant capacity of berberis ethanolic extracts (EB) was determined by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. EB was used to reduce production of reactive substances species (ROS) in zebrafish. EB presented a total polyphenols content of 1,035.03 mg GAE/100 g fresh weight (FW). EB presented an ABTS value of 116.25 ± 17 µmol TE/g FW. EB presented a DPPH value of 137.80 ± 1.90 µmol TE/g FW. EB was able of reducing the ROS in zebrafish. Berberies Protein Isolate (BPI) presented proteins with bands from 15 to 62 kDa. BPI presented an ABTS value of 593.11 ± 8.60 µmol TE/g. The BPI duodenal digest presented a value of 641.07 ± 12.60 µmol TE/g digests. PRACTICAL APPLICATIONS: The practical applications of the present study are to increase scientific knowledge for consumers about the quality and benefits of the consumption of the native fruit (Berberis microphylla) from the Patagonia region of Argentine. This work describes the protein profile of berberies, their digestibility and their antioxidant activity. This study allows to better understand the phytonutrients that make up this fruit. Future studies may identify the peptides present in hydrolyzates. The bio-compounds of this fruit could be used as functional ingredients by the food industry for different purposes.

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BACKGROUND: 'Arauco' is the only autochthonous olive cultivar from Argentina. Little has been reported so far regarding the management of this crop. In this work, variations in fruit and chemical characteristics of olives harvested over a wide range of dates and seasons are reported for this cultivar at two sites in Mendoza province in central west Argentina. RESULTS: During the harvest periods studied, fruit oil content on a dry basis remained at its maximum and was stable, but fruit oil content on fresh basis increased as water content decreased with delay in harvest date. Harvest date affected the maturity index of fruits as well as the oxidative stability and phenolic content of oil. In contrast, the fatty acid profile was not consistently affected by harvest date. Environmental conditions, mainly the occurrence and intensity of frosts, strongly influenced oil quality as well as maturity with delay in harvest date. CONCLUSION: The most appropriate harvest time to obtain Arauco oil with a high oil yield and good chemical quality was before mid-May and with maturity index lower than 2. Fruits harvested after mid-May were exposed to minimum temperatures between -1.2 °C and - 4.0 °C, producing oil with low phenolic compounds and oxidative stability. © 2019 Society of Chemical Industry.

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A powerful chromatographic method coupled to a fluorescence detector was developed to determine the phenolic compounds present in virgin olive oil (VOO), with the aim to propose an appropriate alternative to liquid chromatography-mass spectrometry. An excitation wavelength of 285 nm was selected and four different emission wavelengths (316, 328, 350 and 450 nm) were simultaneously recorded, working therefore on "multi-emission" detection mode. With the use of commercially available standards and other standards obtained by semipreparative high performance liquid chromatography, it was possible to identify simple phenols, lignans, several complex phenols, and other phenolic compounds present in the matrix under study. A total of 26 phenolic compounds belonging to different chemical families were identified (23 of them were susceptible of being quantified). The proposed methodology provided detection and quantification limits within the ranges of 0.004-7.143 µg·mL(-1) and 0.013-23.810 µg·mL(-1), respectively. As far as the repeatability is concerned, the relative standard deviation values were below 0.43% for retention time, and 9.05% for peak area. The developed methodology was applied for the determination of phenolic compounds in ten VOOs, both monovarietals and blends. Secoiridoids were the most abundant fraction in all the samples, followed by simple phenolic alcohols, lignans, flavonoids, and phenolic acids (being the abundance order of the latter chemical classes logically depending on the variety and origin of the VOOs).

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This article reports a simple methodology using dispersive liquid-liquid microextraction combined with CZE. It has been applied for the simultaneous determination of phenolic compounds such as caffeic, gallic, vanillic, syringic, cinnamic, p-coumaric acids and oleuropein, apigenin, luteolin, 3-hydroxytyrosol, and tyrosol, in virgin olive oil (VOO). The optimized extraction conditions for 20 g of VOO were: extractant solvent: 400 µL boric acid 30 mM at pH 9.5; dispersive solvent: 300 µL carbon tetrachloride; vortex: 8 min; centrifugation: 3 min. The composition of the BGE was optimized resulting in the selection of a solution made of 30 mM boric acid at pH 9.5. As a strategy for on-line preconcentration a stacking step was applied, injecting a plug of water before sample injection. The short extraction time, centrifugation and electrophoretic steps allow the selective determination of phenolic compounds in VOO with satisfactory LODs (0.004-0.251 mg/kg), recoveries (89.4-101.0%), and RSD (less than 7.44% in peak area and less than 0.69% in migration time), compatible with the concentration levels present in the samples.

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Olive oil, obtained from Olea europaea L. (Oleaceae) fruits, is an important ingredient in the Mediterranean diet. The purpose of this paper is to review and evaluate olive oil analysis using capillary electrophoresis (CE). This review covers a selection of the literature published on this topic over the past decade. The current state of the art of the topic is evaluated, with special emphasis on separation conditions, analysis purpose, and analytes investigated. CE has been used to characterize or to carry out authenticity studies. Particular attention has been focused on the botanical origin because high-quality monovarietal olive oils have been recently introduced on the markets and their quality control requires the development of new and powerful analytical tools as well as new regulations to avoid fraud. CE represents a good compromise between sample throughput, sample volume, satisfactory characterization, and sustainability for the analysis of target compounds present in olive oils.

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The accurate determination of marker chemical species in grape, musts, and wines presents a unique analytical challenge with high impact on diverse areas of knowledge such as health, plant physiology, and economy. Capillary electromigration techniques have emerged as a powerful tool, allowing the separation and identification of highly polar compounds that cannot be easily separated by traditional HPLC methods, providing complementary information and permitting the simultaneous analysis of analytes with different nature in a single run. The main advantage of CE over traditional methods for wine analysis is that in most cases samples require no treatment other than filtration. The purpose of this article is to present a revision on capillary electromigration methods applied to the analysis of wine and its precursors over the last decade. The current state of the art of the topic is evaluated, with special emphasis on the natural compounds that have allowed wine to be considered as a functional food. The most representative revised compounds are phenolic compounds, amino acids, proteins, elemental species, mycotoxins, and organic acids. Finally, a discussion on future trends of the role of capillary electrophoresis in the field of analytical characterization of wines for routine analysis, wine classification, as well as multidisciplinary aspects of the so-called "from soil to glass" chain is presented.

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A rapid and simple extraction technique based on aqueous two-phase system (ATPS) was developed for separation and enrichment of vitamin B(12) in urine samples. The proposed ATPS-based method involves the application of the hydrophilic ionic liquid (IL) 1-hexyl-3-methylimidazolium chloride and K(2)HPO(4). After the extraction procedure, the vitamin B(12)-enriched IL upper phase was directly injected into the high performance liquid chromatography (HPLC) system for analysis. All variables influencing the IL-based ATPS approach (e.g., the composition of ATPS, pH and temperature values) were evaluated. The average extraction efficiency was 97% under optimum conditions. Only 5.0 mL of sample and a single hydrolysis/deproteinization/extraction step were required, followed by direct injection of the IL-rich upper phase into HPLC system for vitamin B(12) determination. A detection limit of 0.09 µg mL(-1), a relative standard deviation (RSD) of 4.50% (n=10) and a linear range of 0.40-8.00 µg mL(-1) were obtained. The proposed green analytical procedure was satisfactorily applied to the analysis of samples with highly complex matrices, such as urine. Finally, the IL-ATPS technique could be considered as an efficient tool for the water-soluble vitamin B(12) extraction.

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A non-chromatographic separation and preconcentration method for Se species determination based on the use of an on-line ionic liquid (IL) dispersive microextraction system coupled to electrothermal atomic absorption spectrometry (ETAAS) is proposed. Retention and separation of the IL phase was achieved with a Florisil(®)-packed microcolumn after dispersive liquid-liquid microextraction (DLLME) with tetradecyl(trihexyl)phosphonium chloride IL (CYPHOS(®) IL 101). Selenite [Se(IV)] species was selectively separated by forming Se-ammonium pyrrolidine dithiocarbamate (Se-APDC) complex followed by extraction with CYPHOS(®) IL 101. The methodology was highly selective towards Se(IV), while selenate [Se(VI)] was reduced and then indirectly determined. Several factors influencing the efficiency of the preconcentration technique, such as APDC concentration, sample volume, extractant phase volume, type of eluent, elution flow rate, etc., have been investigated in detail. The limit of detection (LOD) was 15 ng L(-1) and the relative standard deviation (RSD) for 10 replicates at 0.5 µg L(-1) Se concentration was 5.1%, calculated with peak heights. The calibration graph was linear and a correlation coefficient of 0.9993 was achieved. The method was successfully employed for Se speciation studies in garlic extracts and water samples.

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A novel method has been developed to determine As-containing animal feed additives including roxarsone (ROX), p-arsanilic acid (p-ASA) and nitarsone (NIT), as well as other organic As species (dimethylarsonic acid (DMAA) and monomethylarsonic acid (MMAA)) by ion-pairing high-performance liquid chromatography coupled to hydride generation atomic fluorescence spectrometry (IP-HPLC-HG-AFS). A simple isocratic reversed-phase (RP) HPLC method with a mobile phase containing citric acid and sodium hexanesulfonate (pH 2.0) was developed using a C(18) column. The use of an organic solvent free mobile phase turns this methodology into an environmentally friendly alternative. Several ion pair forming agents, such as sodium hexanesulfonate, tetrabutylammonium bisulfate and perfluoroheptanoic acid, were studied. The limits of detection for As species were calculated in standard solution and resulted to be 0.2, 0.5, 0.6, 1.6, and 1.6 µg As L(-1) for MMAA, DMAA, p-ASA, ROX and NIT, respectively. This method exhibited convenient operation, high sensitivity and good repeatability. It was applied to As speciation in different samples including arugula, dog food, dog urine and chicken liver.

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An on-line retention and preconcentration system based on a sheep wool-packed microcolumn combined with flame atomic absorption spectrometry is proposed for trace level determination of Cd in wine. A chelating reagent 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol was immobilized onto the wool before retention of the analyte. Several factors influencing the preconcentration efficiency of Cd and his subsequent determination, such as pH, eluent type, sample and eluent flow rates, interfering effects, were studied. A preconcentration factor of 39 was obtained with only 20 mL of sample. The relative standard deviation for five determinations of 1 microg L(-1) Cd was 3.4%. The calibration graph was linear with a correlation coefficient of 0.998 at levels near the detection limit and up to at least 25 microg L(-1). The limit of detection was 37 ng L(-1). The accuracy of the proposed methodology was tested by comparison of the results with those obtained by electrothermal atomic absorption spectrometry analysis along with a recovery study. Finally, the method was employed for evaluating Cd levels in different wines including, blank, rose, and red.

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A sequential on-line preconcentration and separation system for Cr(VI) and Cr(III) species determination was developed in this work. For this purpose, a microcolumn filled with nanostructured alpha-alumina was used for on-line retention of Cr species in a flow-injection system. The method involves the selective elution of Cr(VI) with concentrated ammonia and Cr(III) with 1mol L(-1) nitric acid for sequential injection into an electrothermal atomic absorption spectrometer (ETAAS). Analytical parameters including pH, eluent type, flow rates of sample and eluent, interfering effects, etc., were optimized. The preconcentration factors for Cr(VI) and Cr(III) were 41 and 18, respectively. The limit of detection (LOD) was 1.9 ng L(-1) for Cr(VI) and 6.1 ng L(-1) for Cr(III). The calibration graph was linear with a correlation coefficient of 0.999. The relative standard deviation (RSD) was 8.6% for Cr(VI) and 6.1% for Cr(III) (c = 10 microg L(-1), n=10, sample volume = 25 mL). Verification of the accuracy was carried out by analysis of a standard reference material (NIST SRM 1643e "Trace elements in natural water") with a reported Cr content of 20.40+/-0.24 microg L(-1). Using the proposed methodology the total Cr content, computed as sum of Cr(III) and Cr(VI), in this SRM was 20.26+/-0.96 microg L(-1). The method was successfully applied to the determination of Cr(VI) and Cr(III) species in parenteral solutions. Concentration of Cr(III) species was found to be in the range of 0.29-3.62 microg L(-1), while Cr(VI) species was not detected in the samples under study.

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A novel on-line preconcentration and determination system based on a fiber-packed column was developed for speciation analysis of Cr in drinking water samples prior to its determination by flame atomic absorption spectrometry (FAAS). All variables involved in the development of the preconcentration method including, pH, eluent type, sample and eluent flow rates, interfering effects, etc., were studied in order to achieve the best analytical performance. A preconcentration factor of 32 was obtained for Cr(VI) and Cr(III). The levels of Cr(III) species were calculated by difference of total Cr and Cr(VI) levels. Total Cr was determined after oxidation of Cr(III) to Cr(VI) with hydrogen peroxide. The calibration graph was linear with a correlation coefficient of 0.999 at levels near the detection limit and up to at least 50 microg L(-1). The relative standard deviation (R.S.D.) was 4.3% (C=5 microg L(-1) Cr(VI), n=10, sample volume=25 mL). The limit of detection (LOD) for both Cr(III) and Cr(VI) species was 0.3 microg L(-1). Verification of the accuracy was carried out by the analysis of a standard reference material (NIST SRM 1643e "Trace elements in natural water"). The method was successfully applied to the determination of Cr(III) and Cr(VI) species in drinking water samples.

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