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1.
Molecules ; 25(18)2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32933131

RESUMO

The production of extra virgin olive oil (EVOO) in Brazil developed quite recently, and information on commercial Brazilian EVOO's typical features is very scarce. In just one of the previously published works on Brazilian olive oil, the assessed samples were commercially available. In this study, a comprehensive characterization of EVOO samples acquired at local stores (at Rio de Janeiro and Rio Grande do Sul, from the two most prevalent cultivars, Arbequina and Koroneiki) was carried out considering the most relevant quality parameters, antioxidant capacity, oxidative stability, total phenolic content, fatty acid composition, and minor component metabolic profiling. The latter included: (1) the determination of individual phenolic compounds (belonging to four diverse chemical classes) and triterpenic acids by means of a powerful multi-class reversed-phase LC-MS method; (2) the quantitative profiling of tocopherols, phytosterols, and pigments by normal-phase LC-DAD/fluorescence; and (3) the quantitative appraisal of the volatile pattern of the oils by solid-phase microextraction (SPME)-gas chromatography (GC)-MS. By applying these methods, the concentrations of approximately 70 minor compounds were determined in commercial EVOOs from Brazil. To the best of our knowledge, the content of a very large number of phenolic compounds of those determined in the current report (mainly secoiridoids), the three triterpenic acids (maslinic, betulinic, and oleanolic acids), and the individual chlorophyll derivatives had not been previously evaluated in Brazilian EVOOs. The present work provides a broad picture of the compositional profile and other parameters of relevance of selected commercial Brazilian EVOOs available on local markets, describing their typicity and most particular features, some of which are known to have potential impacts on consumers' health.


Assuntos
Azeite de Oliva/química , Extratos Vegetais/química , Antioxidantes/química , Brasil , Ácidos Graxos/química , Humanos , Óleos Industriais/análise , Iridoides/química , Metaboloma , Fenóis/química , Microextração em Fase Sólida , Esteróis/química , Espectrometria de Massas em Tandem , Tocoferóis/química , Triterpenos/química , Compostos Orgânicos Voláteis/química
2.
Compr Rev Food Sci Food Saf ; 19(6): 3528-3573, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33337049

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are food contaminants whose presence in foodstuffs is especially alarming due to their carcinogenic character. These substances are highly lipophilic and thus, unsafe levels of these compounds have been found in edible fats and oils. Efficient methodologies to determine such molecules in lipidic matrixes are therefore essential. In this review, a detailed description of the analytical methods for the determination of PAHs in vegetable oils from the last 15 years has been provided. Particular emphasis has been placed on innovative sample treatments, which facilitate and shorten the pretreatment of the oils. Finally, results from recent investigations have been reviewed and studied in depth, in order to elucidate which PAHs are most commonly found in vegetable oils.


Assuntos
Óleos de Plantas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Carcinógenos/análise , Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Hidrocarbonetos Policíclicos Aromáticos/química
3.
Molecules ; 23(10)2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30241383

RESUMO

In order to understand the distribution of the main secondary metabolites found in Olea europaea L., eight different samples (olive leaf, stem, seed, fruit skin and pulp, as well as virgin olive oil, olive oil obtained from stoned and dehydrated fruits and olive seed oil) coming from a Picudo cv. olive tree were analyzed. All the experimental conditions were selected so as to assure the maximum coverage of the metabolome of the samples under study within a single run. The use of LC and GC with high resolution MS (through different ionization sources, ESI and APCI) and the annotation strategies within MetaboScape 3.0 software allowed the identification of around 150 compounds in the profiles, showing great complementarity between the evaluated methodologies. The identified metabolites belonged to different chemical classes: triterpenic acids and dialcohols, tocopherols, sterols, free fatty acids, and several sub-types of phenolic compounds. The suitability of each platform and polarity (negative and positive) to determine each family of metabolites was evaluated in-depth, finding, for instance, that LC-ESI-MS (+) was the most efficient choice to ionize phenolic acids, secoiridoids, flavonoids and lignans and LC-APCI-MS was very appropriate for pentacyclic triterpenic acids (MS (-)) and sterols and tocopherols (MS (+)). Afterwards, a semi-quantitative comparison of the selected matrices was carried out, establishing their typical features (e.g., fruit skin was pointed out as the matrix with the highest relative amounts of phenolic acids, triterpenic compounds and hydroxylated fatty acids, and seed oil was distinctive for its high relative levels of acetoxypinoresinol and tocopherols).


Assuntos
Olea/química , Azeite de Oliva/química , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Flavonoides/análise , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Iridoides/química , Lignanas , Metaboloma , Olea/metabolismo , Azeite de Oliva/metabolismo , Fenóis/química , Fitosteróis/química , Metabolismo Secundário , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
4.
Molecules ; 23(10)2018 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-30279368

RESUMO

In Morocco, the recovery of olive agro-industrial by-products as potential sources of high-added value substances has been underestimated so far. A comprehensive quantitative characterization of olive leaves' bioactive compounds is crucial for any attempt to change this situation and to implement the valorization concept in emerging countries. Thus, the phenolic fraction of olive leaves of 11 varieties ('Arbequina', 'Hojiblanca', 'Frantoio', 'Koroneiki', 'Lechín', 'Lucque', 'Manzanilla', 'Picholine de Languedoc', 'Picholine Marocaine', 'Picual' and 'Verdal'), cultivated in the Moroccan Meknès region, was investigated. Thirty eight phenolic or related compounds (including 16 secoiridoids, nine flavonoids in their aglycone form, seven flavonoids in glycosylated form, four simple phenols, one phenolic acid and one lignan) were determined in a total of 55 samples by using ultrasonic-assisted extraction and liquid chromatography coupled to electrospray ionization-ion trap mass spectrometry (LC-ESI-IT MS). Very remarkable quantitative differences were observed among the profiles of the studied cultivars. 'Picholine Marocaine' variety exhibited the highest total phenolic content (around 44 g/kg dry weight (DW)), and logically showed the highest concentration in terms of various individual compounds. In addition, chemometrics (principal components analysis (PCA) and stepwise-linear discriminant analysis (s-LDA)) were applied to the quantitative phenolic compound data, allowing good discrimination of the selected samples according to their varietal origin.


Assuntos
Flavonoides/química , Olea/química , Fenóis/química , Folhas de Planta/química , Flavonoides/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Lignanas , Marrocos , Azeite de Oliva/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Análise de Componente Principal
5.
Int J Mol Sci ; 17(10)2016 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-27669238

RESUMO

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).


Assuntos
Metabolômica , Azeite de Oliva/química , Fenóis/análise , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Espectrometria de Massas , Fenóis/química , Espectrometria de Fluorescência
6.
Int J Mol Sci ; 18(1)2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-28036024

RESUMO

Olive oil phenolic fraction considerably contributes to the sensory quality and nutritional value of this foodstuff. Herein, the phenolic fraction of 203 olive oil samples extracted from fruits of four autochthonous Moroccan cultivars ("Picholine Marocaine", "Dahbia", "Haouzia" and "Menara"), and nine Mediterranean varieties recently introduced in Morocco ("Arbequina", "Arbosana", "Cornicabra", "Frantoio", "Hojiblanca", "Koroneiki", "Manzanilla", "Picholine de Languedoc" and "Picual"), were explored over two consecutive crop seasons (2012/2013 and 2013/2014) by using liquid chromatography-mass spectrometry. A total of 32 phenolic compounds (and quinic acid), belonging to five chemical classes (secoiridoids, simple phenols, flavonoids, lignans and phenolic acids) were identified and quantified. Phenolic profiling revealed that the determined phenolic compounds showed variety-dependent levels, being, at the same time, significantly affected by the crop season. Moreover, based on the obtained phenolic composition and chemometric linear discriminant analysis, statistical models were obtained allowing a very satisfactory classification and prediction of the varietal origin of the studied oils.


Assuntos
Flavonoides/análise , Hidroxibenzoatos/análise , Azeite de Oliva/química , Ácido Quínico/análise , Cromatografia Líquida , Espectrometria de Massas , Marrocos , Olea/química , Olea/genética , Azeite de Oliva/classificação
7.
Food Chem ; 459: 140334, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38981379

RESUMO

Avocado ripening entails intricate physicochemical transformations resulting in desirable characteristics for consumption; however, its impact on specific metabolites and its cultivar dependence remains largely unexplored. This study employed LC-MS to quantitatively monitor 30 avocado pulp metabolites, including phenolic compounds, amino acids, nucleosides, vitamins, phytohormones, and related compounds, from unripe to overripe stages, in three commercial varieties (Hass, Fuerte, and Bacon). Multivariate statistical analysis revealed significant metabolic variations between cultivars, leading to the identification of potential varietal markers. Most monitored metabolites exhibited dynamic quantitative changes. Although phenolic compounds generally increased during ripening, exceptions such as epicatechin and chlorogenic acid were noted. Amino acids and derivatives displayed a highly cultivar-dependent evolution, with Fuerte demonstrating the highest concentrations and most pronounced fluctuations. In contrast to penstemide, uridine and abscisic acid levels consistently increased during ripening. Several compounds characteristic of the Bacon variety were delineated but require further research for identification and role elucidation.

8.
Plants (Basel) ; 12(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37176884

RESUMO

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.

9.
Plants (Basel) ; 12(16)2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37631215

RESUMO

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.

10.
Food Chem ; 408: 135215, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36528992

RESUMO

Exocarp color de-synchronization with softening of 'Hass' avocado is a relevant recurrent problem for the avocado supply chain. This study aimed to unravel the mechanisms driving this de-synchronization integrating omics datasets from avocado exocarp of different storage conditions and color phenotypes. In addition, we propose potential biomarkers to predict color synchronized/de-synchronized fruit. Integration of transcriptomics, proteomics and metabolomics and network analysis revealed eight transcription factors associated with differentially regulated genes between regular air (RA) and controlled atmosphere (CA) and twelve transcription factors related to avocado fruit color de-synchronization control in ready-to-eat stage. CA was positively correlated to auxins, ethylene, cytokinins and brassinosteroids-related genes, while RA was characterized by enrichment of cell wall remodeling and abscisic acid content associated genes. At ready-to-eat higher contents of flavonoids, abscisic acid and brassinosteroids were associated with color-softening synchronized avocados. In contrast, de-synchronized fruit revealed increases of jasmonic acid, salicylic acid and auxin levels.


Assuntos
Frutas , Persea , Frutas/genética , Persea/genética , Ácido Abscísico , Brassinosteroides , Multiômica
11.
J Agric Food Chem ; 71(14): 5674-5685, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36988630

RESUMO

Avocado fruit growth and development, unlike that of other fruits, is characterized by the accumulation of oil and C7 sugars (in most fruits, the carbohydrates that prevail are C6). There are five essential carbohydrates which constitute 98% of the total content of soluble sugars in this fruit; these are fructose, glucose, sucrose, d-mannoheptulose, and perseitol, which together with quinic acid and chlorogenic acid have been the analytes under study in this work. After applying an efficient extraction procedure, a novel methodology based on hydrophilic interaction liquid chromatography coupled to mass spectrometry was applied to determine the levels of these seven substances in tissues─exocarp, seed, and mesocarp─from avocado fruits of two different varieties scarcely studied, Bacon and Fuerte, at three different ripening stages. Quantitative characterization of the selected tissues was performed, and the inter-tissue distribution of metabolites was described. For both varieties, d-mannoheptulose was the major component in the mesocarp and exocarp, whereas perseitol was predominant in the seed, followed by sucrose and d-mannoheptulose. Sucrose was found to be more abundant in seed tissues, with much lower concentrations in avocado mesocarp and exocarp. Quinic acid showed a predominance in the exocarp, and chlorogenic acid was exclusively determined in exocarp samples.


Assuntos
Cromatografia Líquida , Espectrometria de Massas , Persea , Carne de Porco , Carboidratos/análise , Ácido Clorogênico/análise , Cromatografia Líquida/métodos , Frutas/anatomia & histologia , Frutas/química , Manoeptulose/análise , Espectrometria de Massas/métodos , Persea/anatomia & histologia , Persea/química , Carne de Porco/análise , Ácido Quínico/análise , Sementes/química , Sementes/metabolismo , Sacarose/análise
12.
Antioxidants (Basel) ; 12(12)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38136239

RESUMO

Verticillium wilt of olive (VWO) is one of the most widespread and devastating olive diseases in the world. Harnessing host resistance to the causative agent is considered one of the most important measures within an integrated control strategy of the disease. Aiming to understand the mechanisms underlying olive resistance to VWO, the metabolic profiles of olive leaves, stems and roots from 10 different cultivars with varying levels of susceptibility to this disease were investigated by liquid chromatography coupled to mass spectrometry (LC-MS). The distribution of 56 metabolites among the three olive tissues was quantitatively assessed and the possible relationship between the tissues' metabolic profiles and resistance to VWO was evaluated by applying unsupervised and supervised multivariate analysis. Principal component analysis (PCA) was used to explore the data, and separate clustering of highly resistant and extremely susceptible cultivars was observed. Moreover, partial least squares discriminant analysis (PLS-DA) models were built to differentiate samples of highly resistant, intermediate susceptible/resistant, and extremely susceptible cultivars. Root models showed the lowest classification capability, but metabolites from leaf and stem were able to satisfactorily discriminate samples according to the level of susceptibility. Some typical compositional patterns of highly resistant and extremely susceptible cultivars were described, and some potential resistance/susceptibility metabolic markers were pointed out.

13.
Food Chem ; 380: 132205, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35101789

RESUMO

Deep-frying in virgin olive oil (VOO) is favorable due to its desirable composition and high content of bioactive compounds that can be transferred to fried food. The main goal of this work was to investigate the evolution of VOO metabolic profile during consecutive deep-frying cycles and assess the transfer of metabolites to French fries. The evolution of 56 compounds was monitored by two complementary liquid chromatography methods, using mass spectrometry, diode array, and fluorescence detectors. Sterols and lignans were remarkably stable (greater than 70 % retention in frying oil). Seven out of the ten compounds' classes identified in the oil were transferred to the fried food. Potatoes fried in Arbequina oil from Brazil incorporated the highest amounts of VOO minor components, among the analyzed samples, and sterols presented the highest transfer rate. French fries were enriched by VOO bioactive compounds during deep-frying, especially on the first two days, improving their nutritional value.


Assuntos
Culinária , Solanum tuberosum , Temperatura Alta , Metaboloma , Azeite de Oliva , Óleos de Plantas/análise
14.
Plants (Basel) ; 11(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35890425

RESUMO

Olea europaea subsp. cuspidata has a relatively low commercial value due to the low size and pulp to stone ratio of its drupes compared to commercial olive cultivars. Nevertheless, this subspecies could represent a valid source of useful traits for olive breeding. In the current work, the drupe metabolic composition (secoiridoids, flavonoids, simple phenols, triterpenic acids, etc.) of a progeny of 27 cuspidata genotypes coming from free pollination and their female parent was evaluated by applying a powerful LC-MS method. A total of 62 compounds were detected within the profiles; 60 of them were annotated and 27 quantified. From a quantitative point of view, the genotypes from the progeny of cuspidata showed quite different metabolic profiles to olive common cultivars ("Arbequina", "Frantoio", "Koroneiki" and "Picual") used as controls. Cuspidata drupes were richer in terms of several bioactive compounds such as rutin, hydroxytyrosol glucoside, a few interesting secoiridoids and the compounds of m/z 421 and 363. The relationships among several secondary metabolites determined in the progeny inferred from the results of both PCA and cross-correlation analysis were explained according to metabolic biosynthesis pathways in olive drupes. These outcomes underlined the potential of cuspidata genetic resources as a source of potentially interesting variability in olive breeding programs.

15.
Food Chem ; 394: 133447, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35717919

RESUMO

When the recipient of the product is relatively distant from the production area, it is necessary to use cold storage and controlled humidity to transport the avocado fruits. One of the main advantages of local avocado consumption lies on the possibility of prolonging on-tree maturation; this could foreseeably modify the metabolic profile of the fruit that reaches the consumer. In this work, the effect of prolonged on tree maturation (during different time intervals) on the final composition of avocado fruit (at edible ripeness) was evaluated and compared with the impact of the same periods after prolonged cold storage. The quantitative evolution of nine bioactive metabolites (7 phenolic compounds, pantothenic and abscisic acids) over 40 days (10-days intervals) was studied by using a solid-liquid extraction protocol and a LC-MS methodology. The results were discussed both considering the quantitative evolution of each individual compound and the sum of all of them.


Assuntos
Persea , Ácido Abscísico/metabolismo , Cromatografia Líquida , Frutas/metabolismo , Persea/metabolismo , Árvores
16.
Antioxidants (Basel) ; 11(7)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35883723

RESUMO

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.

17.
J Pharm Biomed Anal ; 221: 115060, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36166933

RESUMO

Short-chain carboxylic acids (SCCAs) produced by gut microbial fermentation may reflect gastrointestinal health. Their concentrations in serum and urine are indicative of specific metabolic pathway activity; therefore, accurate quantitation of SCCAs in different biofluids is desirable. However, it is often challenging to quantitate SCCAs since matrix effects, induced by the presence of a vast variety of other compounds other than SCCAs in complex biofluids, can suppress or enhance signals. Materials used for sample preparation may introduce further analytical challenges. This study reports for the first time a LC-MS/MS-based method to quantitate ten SCCAs (lactate, acetate, 2-hydroxybutyrate, propionate, isobutyrate, butyrate, 2-methylbutyrate, isovalerate, valerate and hexanoate) and evaluates the matrix effects in five human biofluids: serum, urine, stool, and contents from the duodenum and intestinal stoma bags. The optimized method, using 3-Nitrophenylhydrazone as a derivatization agent and a Charge Surface Hybrid reverse phase column, showed clear separation for all SCCAs at a concentration range of 0.1-100 µM, in a 10.5 min run without carry-over effects. The validation of the method showed a good linearity (R2 > 0.99), repeatability (CV ≤ 15%) assessed by intra- and inter-day monitoring. The lowest limit of detection (LLOD) was 25 nM and lowest limit of quantitation (LLOQ) was 50 nM for nine SCCA except acetate at 0.5 and 1 µM, respectively. Quantitative accuracy in all biofluids for most compounds was < ±15%. In summary, this methodology has the advantages over other techniques for its simple and fast sample preparation and a high level of selectivity, repeatability and robustness for SCCA quantification. It also reduced interferences from the matrix or sample containers, making it ideal for use in high-throughput analyses of biofluid samples from large-scale studies.


Assuntos
Caproatos , Espectrometria de Massas em Tandem , Ácidos Carboxílicos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Humanos , Hidroxibutiratos , Isobutiratos , Lactatos , Fenil-Hidrazinas , Propionatos , Espectrometria de Massas em Tandem/métodos , Valeratos
18.
ACS Omega ; 6(48): 32631-32636, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34901611

RESUMO

Two undescribed 4'-O-methylkaempferol-[3″,4″-di-p-coumaroyl]-α-l-rhamnopyranosides, caerulines A and B (1-2), along with three known 4'-O-methylkaempferol diacylrhamnosides isomers (3-5) were isolated from an ethanol extract of the leaves of Persea caerulea, a native plant growing on the Colombian Caribbean coast. The chemical structures of 1 and 2 were elucidated by spectroscopic methods. The effect of compounds 1-5 against four pathogenic microorganisms [i.e., methicillin-resistant Staphylococcus aureus (MRSA), Acinetobacter baumannii, Candida albicans, and Aspergillus fumigatus] was tested in vitro. The compounds exhibited no activity against these pathogens except MRSA (MIC 12-48 µg/mL). Caeruline B (2) was found to be the most active compound with a modest anti-MRSA activity (MIC = 12 µg/mL).

19.
Food Res Int ; 125: 108649, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554121

RESUMO

For the first time, a multi-class GC-MS method was applied to perform the quantitative-profiling of the minor fraction of VOOs (considering >40 compounds) in a single run. This comprehensive methodology has demonstrated a remarkable profiling ability on five groups of compounds (phenolic and triterpenic compounds, tocopherols, sterols and free fatty acids) with wide range of polarities/volatilities and chemical entities. After the complete analytical validation of the method, 32 VOO samples from eight different cultivars (some of them very scarcely studied before) were analyzed and the quantitative results were subjected to both non-supervised and supervised multivariate statistics for testing the capability of the determined VOO minor compounds to discriminate the varietal origin of the samples. Typical compositional profiles were defined for each cultivar and promising potential varietal markers were pointed out. The models built to discriminate Cayon and Maurino samples from the rest exhibited the best quality parameters. The relative levels of tocopherols together with characteristic concentration of luteolin, ß-sitosterol and tyrosol were, for instance, the most specific features of Cayon VOOs.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Azeite de Oliva/química , Azeite de Oliva/classificação , Ácidos Graxos não Esterificados/análise , Fenóis/análise , Fitosteróis/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie , Tocoferóis/análise , Triterpenos/análise
20.
J Agric Food Chem ; 67(33): 9295-9306, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31365237

RESUMO

As a result of an innovative olive fruit processing method involving stone removal and dehydration, a new kind of olive oil and olive flour are generated. The main objective of this work was to accomplish the comprehensive characterization of the minor compounds of both products and to evaluate the effect of the dehydration temperature on their composition. To this end, olive oil and flour samples obtained through the novel processing method were analyzed and compared with "conventional" virgin olive oils (VOO). The applied LC-MS methodology allowed the determination of 57 metabolites belonging to different chemical classes (phenolic compounds, pentacyclic trirterpenes, and tocopherols). Both the new oils and flours presented considerable amounts of olive fruit metabolites that are usually absent from VOO. Quantitative differences were found among VOOs and the new oils, probably due to the inhibition of some enzymes caused by the temperature increase or the absence of water during the processing.


Assuntos
Manipulação de Alimentos/métodos , Olea/química , Extratos Vegetais/química , Resíduos/análise , Cromatografia Líquida , Farinha/análise , Frutas/química , Azeite de Oliva/análise , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas em Tandem , Tocoferóis/química , Tocoferóis/isolamento & purificação
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