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1.
Molecules ; 24(19)2019 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-31557931

RESUMEN

Olive tree (Olea europaea L.) leaf, a waste by-product of the olive oil industry, is an inexpensive and abundant source of biophenols of great interest for various industrial applications in the food supplement, cosmetic, and pharmaceutical industries. In this work, the aqueous extraction of high-added value compounds from olive leaves by using microfiltered (MF), ultrapure (U), and osmosis-treated (O) water was investigated. The extraction of target compounds, including oleuropein (Olp), hydroxytyrosol (HyTyr), tyrosol (Tyr), verbascoside (Ver), lutein (Lut), and rutin (Rut), was significantly affected by the characteristics of the water used. Indeed, according to the results of liquid chromatography tandem mass spectrometry, the extracting power of microfiltered water towards rutin resulted very poor, while a moderate extraction was observed for oleuropein, verbascoside, and lutein. On the other hand, high concentrations of hydroxytyrosol were detected in the aqueous extracts produced with microfiltered water. The extraction power of ultrapure and osmosis-treated water proved to be very similar for the bio-active compounds oleuropein, verbascoside, lutein, and rutin. The results clearly provide evidence of the possibility of devising new eco-friendly strategies based on the use of green solvents which can be applied to recover bioactive compounds from olive leaves.


Asunto(s)
Suplementos Dietéticos/análisis , Olea/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Fraccionamiento Químico , Cromatografía Liquida , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
2.
Biochim Biophys Acta Bioenerg ; 1859(9): 984-996, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29626418

RESUMEN

Here, we show that a 2:1 mixture of Brutieridin and Melitidin, termed "BMF", has a statin-like properties, which blocks the action of the rate-limiting enzyme for mevalonate biosynthesis, namely HMGR (3-hydroxy-3-methylglutaryl-CoA-reductase). Moreover, our results indicate that BMF functionally inhibits several key characteristics of CSCs. More specifically, BMF effectively i) reduced ALDH activity, ii) blocked mammosphere formation and iii) inhibited the activation of CSC-associated signalling pathways (STAT1/3, Notch and Wnt/beta-catenin) targeting Rho-GDI-signalling. In addition, BMF metabolically inhibited mitochondrial respiration (OXPHOS) and fatty acid oxidation (FAO). Importantly, BMF did not show the same toxic side-effects in normal fibroblasts that were observed with statins. Lastly, we show that high expression of the mRNA species encoding HMGR is associated with poor clinical outcome in breast cancer patients, providing a potential companion diagnostic for BMF-directed personalized therapy.


Asunto(s)
Productos Biológicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Hidroximetilglutaril-CoA Reductasas/metabolismo , Ácido Mevalónico/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Aceites de Plantas/química , Inhibidores de la Disociación del Nucleótido Guanina rho-Específico/metabolismo , Apoptosis/efectos de los fármacos , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Femenino , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Metástasis de la Neoplasia , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Pronóstico , Transducción de Señal/efectos de los fármacos , Tasa de Supervivencia
3.
Chem Cent J ; 11(1): 111, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-29098462

RESUMEN

This work compares the composition at different temperatures of gaseous phase of bergamot essential oil at equilibrium with the liquid phase. A new GC-MS methodology to determine quantitatively the volatile aroma compounds was developed. The adopted methodology involved the direct injection of headspace gas into injection port of GC-MS system and of known amounts of the corresponding authentic volatile compounds. The methodology was validated. This study showed that gaseous phase composition is different from that of the liquid phase at equilibrium with it.

4.
J Mass Spectrom ; 51(9): 761-7, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27460885

RESUMEN

A novel approach for the rapid discrimination of bergamot essential oil from other citrus fruits oils is presented. The method was developed using paper spray mass spectrometry (PS-MS) allowing for a rapid molecular profiling coupled with a statistic tool for a precise and reliable discrimination between the bergamot complex matrix and other similar matrices, commonly used for its reconstitution. Ambient mass spectrometry possesses the ability to record mass spectra of ordinary samples, in their native environment, without sample preparation or pre-separation by creating ions outside the instrument. The present study reports a PS-MS method for the determination of oxygen heterocyclic compounds such as furocoumarins, psoralens and flavonoids present in the non-volatile fraction of citrus fruits essential oils followed by chemometric analysis. The volatile fraction of Bergamot is one of the most known and fashionable natural products, which found applications in flavoring industry as ingredient in beverages and flavored foodstuff. The development of the presented method employed bergamot, sweet orange, orange, cedar, grapefruit and mandarin essential oils. PS-MS measurements were carried out in full scan mode for a total run time of 2 min. The capability of PS-MS profiling to act as marker for the classification of bergamot essential oils was evaluated by using multivariate statistical analysis. Two pattern recognition techniques, linear discriminant analysis and soft independent modeling of class analogy, were applied to MS data. The cross-validation procedure has shown excellent results in terms of the prediction ability because both models have correctly classified all samples for each category. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Espectrometría de Masas/métodos , Aceites Volátiles/análisis , Aceites de Plantas/análisis , Aceites Volátiles/química , Aceites de Plantas/química , Análisis de Componente Principal , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Food Chem ; 162: 89-93, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24874361

RESUMEN

Phenolic compounds present in extra virgin olive oil have attracted considerable recent attention. Many of them, show specific anti-inflammatory and anti-tumor activities. In this work we describe the biomimetic synthesis of 3,4-DHPEA-EDA [2-(3,4-hydroxyphenyl) ethyl (3S,4E)-4-formyl-3-(2-oxoethyl)hex-4-enoate], starting from natural demethyloleuropein present in olive tissues. A comparison between 3,4-DHPEA-EDA (6) and oleuropein (1), oleuropein aglycone (4) and hydroxytyrosol ORACFL values was undertaken.


Asunto(s)
Antioxidantes/química , Biomimética/métodos , Fenoles/química , Aceites de Plantas/química , Piranos/química , Antiinflamatorios , Humanos , Estructura Molecular , Aceite de Oliva
6.
Phytochem Anal ; 25(3): 207-12, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24375682

RESUMEN

INTRODUCTION: Vegetables contain a variety of phytochemicals that have the ability to modify enzymatic and chemical reactions, and therefore may have a positive influence on human health. In particular kaempferol is known to possess anti-carcinogenic activity. OBJECTIVE: The purpose of this work was to determine the structure of glycosylated kaempferol derivatives, acylated with malonic acid on the sugar portion. METHODS: A methanolic extract of the leaves of Allium porrum L. was submitted to fractionation procedures through semi-preparative HPLC/UV-MS techniques. The collected fractions were evaluated by accurate tandem mass spectrometry experiments using an electrospray ionisation (ESI) quadrupole time-of-flight instrument. Isolated compounds were hydrolysed in order to obtain information on the ester moieties. RESULTS: The structures of five compounds not previously reported in leek were determined. The molecules are mono-hexose, di-hexose and coumaroyl, feruloyl and caffeoyl acylated di-hexose derivatives of kaempferol. The common characteristic of the structures relies on the presence of the malonyl moiety on the primary alcoholic function of the sugar immediately linked to the aglycone. Accurate tandem MS experiments and basic hydrolysis treatments revealed a sequence of the acylated glycosidic moieties. CONCLUSION: A set of secondary metabolites of the aerial part of Allium porrum L. (leek) was identified and characterised by ESI/MS(2) . Knowledge of the presence of these first-reported compounds in leek could provide the means for fully understanding of the metabolism of this plant in relation to the biosynthesis of the phenolics.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Flavonoles/aislamiento & purificación , Cebollas/química , Extractos Vegetales/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Flavonoles/química , Glicosilación , Quempferoles/química , Quempferoles/aislamiento & purificación , Malonatos/química , Estructura Molecular , Componentes Aéreos de las Plantas/química , Extractos Vegetales/química
7.
Anal Chim Acta ; 747: 58-66, 2012 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-22986136

RESUMEN

A new analytical approach is exploited in the assay of selenium speciation in selenized and not selenium enriched potatoes based on the widely available solid-phase microextraction (SPME) coupled to-GC-triple quadrupole mass spectrometry (SPME-GC-QqQ MS) method. The assay of selenomethionine (SeMet) and selenomethylselenocysteine (SeMeSeCys) in potatoes here reported provides clues to the effectiveness of SPME technique combined with gas chromatography-tandem mass spectrometry, which could be of general use. For the exploitation of the GC method, the selected analytes were converted into their N(O,S)-alkoxycarbonyl alkyl esters derivatives by direct treatment with alkyl chloroformate in aqueous extracts. The performance of five SPME fibers and three chloroformates were tested in univariate mode and the best results were obtained using the divinylbenzene/carboxen/polydimethylsiloxane fiber and propylchloroformate. The variables affecting the efficiency of SPME analysis were optimized by the multivariate approach of design of experiment (DoE) and, in particular, a central composite design (CCD) was applied. Tandem mass spectrometry in selected reaction monitoring (SRM) has allowed the elimination of matrix interferences, providing reconstructed chromatograms with well-resolved peaks and the achievement of very satisfactory detection and quantification limits. Both precision and recovery of the proposed protocol tested at concentration of 8 and 40 µg kg(-1) (dry matter), offered values ranging from 82.3 to 116.3% and from 8.5 to 13.1% for recovery and precision, respectively. The application of the method to commercial samples of selenized and not selenium enriched potatoes proved that the Se fertilization increases significantly the concentration of these bioavailable selenoamino acids.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Selenocisteína/análogos & derivados , Selenometionina/análisis , Microextracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Agua/química , Humanos , Límite de Detección , Extractos Vegetales/química , Reproducibilidad de los Resultados , Proyectos de Investigación , Selenio/metabolismo , Selenocisteína/análisis , Solanum tuberosum
8.
Food Chem ; 135(3): 1006-10, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22953817

RESUMEN

Hydroxytyrosol and tyrosol, the strong antioxidant present in large amount in virgin olive oil have been assayed by LC-MS/MS under MRM condition and isotope dilution method, using d(2)-labelled internal standards obtained by simple synthetic procedures. The assay has been performed under MRM condition monitoring two transitions for each analyte to improve the specificity. This paper deals with a modern approach for assaying the content of this polyphenols in virgin olive oil down to a limit of a few hundreds of parts per billion. Tyrosol and hydroxytyrosol ranged from 10 to 47ppm and from 5 to 25ppm in commercial olive oil, respectively. The accuracy (98-107%) and analytical parameters values confirm the reliability of the proposed approach. The method can be extended to any natural matrices, including mill wastes, after a simple step of sample preparation.


Asunto(s)
Antioxidantes/química , Marcaje Isotópico/métodos , Alcohol Feniletílico/análogos & derivados , Aceites de Plantas/química , Espectrometría de Masas en Tándem/métodos , Aceite de Oliva , Alcohol Feniletílico/química
9.
J Mass Spectrom ; 47(9): 1247-53, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22972793

RESUMEN

The role of lipase to catalyze hydrolysis and transesterification of triacylglycerols (TAGs) was evaluated in model systems as well as in virgin olive oil. Tandem mass spectrometry was applied in the identification of modified TAGs, ionized by electrospray, formed during the incubation of selected TAGs with mono and di carboxylic acids. The oligomerization of TAGs was observed in authentic olive oil samples and verified in model systems under catalysis exerted by lipase, whose presence in olive oil was already documented. The hydrolytic pathways taken under enzymatic treatment is balanced by the formation of TAG oligomers that should not alter the nutritional value of the aliment.


Asunto(s)
Lipasa/metabolismo , Aceites de Plantas/química , Aceites de Plantas/metabolismo , Triglicéridos/química , Triglicéridos/metabolismo , Esterificación , Isomerismo , Cinética , Aceite de Oliva , Espectrometría de Masa por Ionización de Electrospray , Ácido Succínico/química , Ácido Succínico/metabolismo , Espectrometría de Masas en Tándem , Temperatura
10.
ScientificWorldJournal ; 2012: 532179, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22645430

RESUMEN

The quality of olive oil is influenced by genetic and environmental factors and by the maturation state of drupes, but it is equally affected by technological treatments of the process. This work investigates the possible correlation between olive LOX gene transcript accumulation, evaluated in fruits collected at different stages of maturation, and chemical biomarkers of its activity. During olive fruit ripening, the same genotype harvested from two different farms shows a positive linear trend between LOX relative transcript accumulation and the content of volatile compounds present in the olive oil aroma. Interestingly, a negative linear trend was observed between LOX relative transcript accumulation and the content of volatile compounds present in the olive pastes obtained from olive fruits with and without malaxation. The changes in the olive LOX transcript accumulation reveal its environmental regulation and suggest differential physiological functions for the LOXs.


Asunto(s)
Lipooxigenasas/biosíntesis , Lipooxigenasas/genética , Olea/metabolismo , Biomarcadores/metabolismo , Cartilla de ADN/genética , Ambiente , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Genotipo , Geografía , Lípidos/química , Modelos Químicos , Modelos Genéticos , Aceite de Oliva , Aceites de Plantas/análisis , ARN Mensajero/metabolismo , Especificidad de la Especie
11.
J Agric Food Chem ; 59(15): 8450-7, 2011 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-21721527

RESUMEN

Tropea red onion ( Allium cepa L. var. Tropea) is among the most highly appreciated Italian products. It is cultivated in specific areas of Calabria and, due to its characteristics, was recently awarded with the protected geographical indications (PGI) certification from the European Union. A reliable classification of onion samples in groups corresponding to "Tropea" and "non-Tropea" categories is now available to the producers. This important goal has been achieved through the evaluation of three supervised chemometric approaches. Onion samples with PGI brand (120) and onion samples not cultivated following the production regulations (80) were digested by a closed-vessel microwave oven system. ICP-MS equipped with a dynamic reaction cell was used to determine the concentrations of 25 elements (Al, Ba, Ca, Cd, Ce, Cr, Dy, Eu, Fe, Ga, Gd, Ho, La, Mg, Mn, Na, Nd, Ni, Pr, Rb, Sm, Sr, Tl, Y, and Zn). The multielement fingerprint was processed using linear discriminant analysis (LDA) (standard and stepwise), soft independent modeling of class analogy (SIMCA), and back-propagation artificial neural network (BP-ANN). The cross-validation procedure has shown good results in terms of the prediction ability for all of the chemometric models: standard LDA, 94.0%; stepwise LDA, 94.5%; SIMCA, 95.5%; and BP-ANN, 91.5%.


Asunto(s)
Espectrometría de Masas/métodos , Cebollas/química , Oligoelementos/análisis , Análisis Discriminante , Italia , Cebollas/normas , Control de Calidad
12.
Anal Chem ; 83(6): 1990-5, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21329394

RESUMEN

The quality of extra virgin olive oil is associated with the presence of microcomponents whose healing effects have been proved in some special cases. The enzymatic hydrolysis of oleuropein and ligstroside, and of their demethylated analogues, affords four different pentanedialdehydes, and for one of which, 2-(4-hydroxyphenyl)ethyl (3S,4E)-4-formyl-3-(2-oxoethyl)hex-4-enoate, also known as oleocanthal, an anti-inflammatory effect was quite recently carefully assessed. Extra virgin olive oil is now worldwide considered as a functional food whose daily intake, as for the Mediterranean diet, helps consumers in keeping a constant level of nonsteroidal anti-inflammatory drug (NSAID) in the blood. The presence of these active principles provides, therefore, olive oil with an important added value. In the framework of the actions of the recently funded Agrifood Regional Center, which should coordinate the scientific research and production worlds, an absolute analytical method was developed for the mass spectrometric detection of the two most abundant NSAIDs, Tyr-OLPD and HTyr-OLPD (oleopentanedialdehydes (OLPDs) conjugated to p-hydroxyphenylethanol and 3,4-dihydroxyphenylethanol, respectively), by UHPLC-ESI-MS/MS.


Asunto(s)
Aldehídos/análisis , Aldehídos/química , Cromatografía Líquida de Alta Presión/métodos , Aceites de Plantas/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/normas , Límite de Detección , Aceite de Oliva , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray/normas , Espectrometría de Masas en Tándem/normas
13.
Molecules ; 15(12): 8734-46, 2010 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-21124271

RESUMEN

The quality of olive oils is sensorially tested by accurate and well established methods. It enables the classification of the pressed oils into the classes of extra virgin oil, virgin oil and lampant oil. Nonetheless, it would be convenient to have analytical methods for screening oils or supporting sensorial analysis using a reliable independent approach based on exploitation of mass spectrometric methodologies. A number of methods have been proposed to evaluate deficiencies of extra virgin olive oils resulting from inappropriate technological treatments, such as high or low temperature deodoration, and home cooking processes. The quality and nutraceutical value of extra virgin olive oil (EVOO) can be related to the antioxidant property of its phenolic compounds. Olive oil is a source of at least 30 phenolic compounds, such as oleuropein, oleocanthal, hydroxytyrosol, and tyrosol, all acting as strong antioxidants, radical scavengers and NSAI-like drugs. We now report the efficacy of MRM tandem mass spectrometry, assisted by the isotope dilution assay, in the evaluation of the thermal stability of selected active principles of extra virgin olive oil.


Asunto(s)
Antioxidantes/análisis , Análisis de los Alimentos/métodos , Calor , Fenoles/análisis , Aceites de Plantas/química , Espectrometría de Masas en Tándem/métodos , Antioxidantes/química , Culinaria , Aceite de Oliva , Fenoles/química , Aceites de Plantas/análisis
14.
Rapid Commun Mass Spectrom ; 23(23): 3803-6, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19908221

RESUMEN

A new approach for the assay of rotenone (1) by isotope dilution mass spectrometry is presented. The extreme toxicity of rotenone, a natural phytodrug with insecticidal and piscicidal activity, recently banned by national and international environmental protection agencies, calls for the development of sensitive and accurate methods of analyses. Accordingly, the proposed protocol is based on the availability of the labeled internal standard rotenone-d3 (3) which can be conveniently prepared by consecutive and specific mono-O-demethylation, and remethylation with methyl iodide-d3. The sensitivity of the method is confirmed by the very low limit of detection (LOD) and quantitation (LOQ) values achieved in the assay of 1 in two distinct fortified matrices, and is further supported by the observed accuracy values.


Asunto(s)
Cromatografía Liquida/métodos , Aceites de Plantas/química , Ríos/química , Rotenona/análisis , Espectrometría de Masas en Tándem/métodos , Aceite de Oliva , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
J Agric Food Chem ; 57(23): 11161-7, 2009 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-19908866

RESUMEN

Oleuropein, the main phenolic compound in virgin olive oil, and several of its derivatives such as oleuropein aglycone, hydroxytyrosol, and their respective acetylated lipophilic forms were obtained by simple and environmentally friendly semisynthetic protocols. The same molecules were then tested in vitro and in vivo, comparing their intriguing anti-COX-1 and anti-COX-2 properties to those of well-known anti-inflammatory drugs such as ibuprofen and celecoxib. Finally, molecular modeling experiments displaying the most probable binding modes within the classical binding clefts of the enzymes suggest the heme moiety as a potential alternative target.


Asunto(s)
Inhibidores de la Ciclooxigenasa/química , Olea/química , Piranos/química , Sitios de Unión , Inhibidores de la Ciclooxigenasa/síntesis química , Glucósidos Iridoides , Iridoides , Conformación Molecular , Extractos Vegetales/química , Prostaglandina-Endoperóxido Sintasas/química , Unión Proteica , Piranos/síntesis química
16.
Rapid Commun Mass Spectrom ; 23(19): 3057-62, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19705382

RESUMEN

A fast, reagentless, and direct method is presented for the mass spectrometric analysis of olive oil without any sample pretreatment whatsoever. An ambient ionization technique, the low-temperature plasma (LTP) probe, based on dielectric barrier discharge, is used to detect both minor and trace components (free fatty acids, phenolics and volatiles) in raw untreated olive oil. The method allows the measurement of free fatty acids (the main quality control parameter used to grade olive oil according to quality classes), selected bioactive phenolic compounds, and volatiles. The advantages and limitations of the direct analysis of extremely complex mixtures by the ambient ionization/tandem mass spectrometry combination are discussed and illustrated. The data presage the possible large-scale application of direct mass spectrometric analysis methods in the characterization of olive oil and other foodstuffs.


Asunto(s)
Aceites de Plantas/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Frío , Aceite de Oliva
17.
Rapid Commun Mass Spectrom ; 23(10): 1515-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19370544

RESUMEN

Crop control is an important issue in both developed and developing countries. An environmentally friendly approach is represented by the so-called Integrated Pest Management (IPM), whereby synthetic pesticides are only applied as a last resort, under the strict control of suitable experts. European and US regulatory authorities, such as the US EPA, are constantly assessing the risks of exposure to the organophosphate (OP) class of pesticides and, among these, specifically dimethoate. The use of dimethoate is still allowed in many crops, including olives, which once was based in the Mediterranean area but now is expanding rapidly throughout the world. An important aspect of IPM protocols is represented by the availability of reliable and sensitive methods to detect pesticides residues. This paper describes an isotope dilution dimethoate assay based on the application of electrospray ionization tandem mass spectrometry (ESI-MS/MS) by means of a deuterium-labeled internal standard.


Asunto(s)
Deuterio/análisis , Dimetoato/análisis , Contaminación de Alimentos/análisis , Residuos de Plaguicidas/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Malus/química , Aceite de Oliva , Aceites de Plantas/química , Solanum tuberosum/química , Spinacia oleracea/química
18.
J Chromatogr A ; 1205(1-2): 137-43, 2008 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-18755465

RESUMEN

A gas chromatography-tandem mass spectrometry (GC-MS/MS) method for the detection of six phthalates in olive oil was developed. A gel permeation chromatography (GPC) clean-up step with cyclohexane:dichoromethane 7:3 as mobile phase was employed to remove the high-molecular mass species present in oil. Two ionization methodologies, i.e. electron (EI) and isobutane-chemical ionization (CI), were compared, in MS/MS mode, to achieve better analytical performances. An overall evaluation of all analytical parameters shows that the EI-MS/MS approach provides satisfactory results and is to be preferred to CI-MS/MS, at least in the case of the examined analytes. The observed accuracies, ranging from 71.7% to 112.2%, and the RSD values less than 9.7%, confirm the effectiveness of the proposed method in the assay of phthalate content in such a complex matrix as olive oil. The proposed protocol for the identification and assay of phthalates in olive oil might be of interest for the implementation of the QS (quality assurance scheme) for residue monitoring in food safety assessment.


Asunto(s)
Contaminación de Alimentos/análisis , Ácidos Ftálicos/análisis , Aceites de Plantas/química , Espectrometría de Masas en Tándem/métodos , Seguridad de Productos para el Consumidor , Cromatografía de Gases y Espectrometría de Masas/métodos , Aceite de Oliva , Reproducibilidad de los Resultados , Incertidumbre
19.
Rapid Commun Mass Spectrom ; 21(22): 3653-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17939156

RESUMEN

A set of minor constituents of Olea europaea L. leaves have been identified and characterized by electrospray ionization tandem mass spectrometry (ESI-MS/MS) and high-resolution measurements (HRMS). Most of them are modified hydroxytyrosol species conjugated to a hexose unit. When possible, the structures of the new phenolic compounds present in Olea europaea L. have been confirmed by matching their MS/MS spectra with those of authentic standards isolated from other plants of the oleaceae family. The knowledge of the presence of new phenolic species in Olea europaea L. could provide tools for a full understanding of the secondary metabolism of this plant in relation to the biosynthesis of the phenolic species.


Asunto(s)
Olea/química , Fenoles/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Extractos Vegetales/química , Hojas de la Planta/química
20.
Anal Chim Acta ; 585(2): 366-70, 2007 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-17386687

RESUMEN

Multi-element analysis of organic virgin olive oils from different Italian regions was carried out by inductively coupled plasma mass spectrometry (ICP-MS) aiming at developing a reliable method in the traceability of the origin of oils. The data were processed by means of the chemiometric approach of linear discriminant analysis (LDA) that allows classifying unknown samples after checking possible differentiation of samples of known origin. An external calibration curve was build for the quantitative analysis. The calibration curves for each element were linear in the range between 0.01 and 100 ng mL(-1) and 0.2 to 2000 ng mL(-1), the correlation coefficients were ranging between 0.996 and 0.999. Results from spike and recovery experiments at levels of 30 and 65 ng mL(-1) were in the range of 91-119%, whereas the quantitation limits, based on 10 times standard deviation of the blank, were also in the range of 0.009-10.2 ng g(-1), for almost all the elements.


Asunto(s)
Técnicas de Química Analítica/métodos , Análisis de los Alimentos/métodos , Contaminación de Alimentos , Espectrometría de Masas/métodos , Oligoelementos/análisis , Calibración , Geografía , Modelos Estadísticos , Modelos Teóricos , Aceite de Oliva , Aceites de Plantas , Reproducibilidad de los Resultados
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