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A wide number of analytical terms have been applied erroneously for many years by analytical chemists, and they apply at present yet, by considering the time makes their use correct. The question is, may precedents validate the present use of incorrect scientific terms? Misused terms are found along the analytical process, starting with giving the name of the sample to the exiguous fraction of the original sample that reaches the detector or the high-resolution equipment after sample pretreatment and sample preparation. All the steps of the analytical process are considered in this article, with special emphasis on sample preparation and, within this, on the use of ultrasound, mainly for assisting extraction more unequivocally named as leaching or lixiviation. A call of attention in this respect is considered by the author to be of help to the analytical community.
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BACKGROUND: Recent technological advances to improve the quality of virgin olive oil (VOO) have been focused on olive breeding programs by selecting outstanding cultivars and target progenies. Fatty acid (FA) composition, with special emphasis on oleic acid (C18:1) and palmitic acid (C16:0), is one of the most critical quality factors to be evaluated in VOO. For this reason, the profile of FAs is frequently used as a decision tool in olive breeding programs. RESULTS: A method based on gas chromatography with flame ionization detection (GC-FID) was used to study the influence of genotype on the concentration of ten of the most important FAs in VOOs from target crosses Arbequina × Arbosana, Picual × Koroneiki and Sikitita × Arbosana and their corresponding genitors Arbequina, Arbosana, Koroneiki, Picual and Sikitita. For this purpose, a targeted approach was selected for determination of esterified FAs (EFAs) and non-esterified FAs (NEFAs) in a dual analysis by the same chromatographic method. A Pearson analysis revealed correlations between pairs of FAs, which allowed detecting metabolic connections through desaturation and elongation enzymes. An ANOVA test (with P < 0.01) led to identification of C16:0 EFA, C16:1 EFA and C18:1 EFA and also C16:1 NEFA and C18:0 NEFA as the FAs more influenced by cross breeding. Statistical analysis was carried out by unsupervised analysis using principal component analysis (PCA) and cluster analysis (CA) to look for variability sources. CONCLUSION: Crosses with a common genitor (Arbequina × Arbosana and Sikitita × Arbosana) were partially overlapped in the PCAs using the profile of FAs. The CA results revealed clear differences between Sikitita × Arbosana and Picual × Koroneiki crosses in the composition of the most significant FAs, while Arbequina × Arbosana was not properly discriminated from the other crosses.
Assuntos
Ácidos Graxos/análise , Genótipo , Olea/química , Azeite de Oliva/química , Melhoramento Vegetal , Cruzamento , Cromatografia Gasosa , Ácidos Graxos/genética , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/genética , Ionização de Chama , Humanos , Olea/genética , Ácido Oleico/análise , Ácido Oleico/genética , Ácido Palmítico/análise , Especificidade da EspécieRESUMO
BACKGROUND: The growing demand for high-quality virgin olive oils (VOOs) has increased the interest in olive breeding programs. Cross-breeding is considered, within these programs, the best strategy to generate new cultivars as an attempt to improve the present cultivars. In this research, the phenolic profile of VOOs from target crosses (Arbequina × Arbosana, Picual × Koroneiki and Sikitita × Arbosana) and their corresponding genitors (Arbequina, Arbosana, Koroneiki, Picual and Sikitita) has been evaluated using a targeted metabolomics approach. RESULTS: The phenolic profiles were obtained by liquid chromatographic-hybrid quadrupole time-of-flight mass spectrometric targeted analysis of 37 phenols or compounds involved in the main pathways for their biosynthesis. Statistical multivariate analysis by principal component analysis was applied to study the influence of genotype on phenol composition. Phenolic compounds with the highest contribution to explain the observed variability associated to genotype were identified through fold change algorithms (cut-off > 2.0) and t-test analysis. CONCLUSION: A total of nine phenols (viz. quercetin, ligstroside aglycon (p-HPEA-EA), demethyl oleuropein aglycon, oleuropein aglycon (3,4-DHPEA-EA), hydroxypinoresinol, hydroxytyrosol and phenolic acids such as p-coumaric acid, ferulic acid and protocatechuic acid) contributed to explain the observed variability with 99% confidence (P<0.01).
Assuntos
Hibridização Genética , Espectrometria de Massas/métodos , Olea/genética , Fenóis/análise , Óleos de Plantas/química , Cromatografia Líquida , Genótipo , Metabolômica/métodos , Análise Multivariada , Azeite de OlivaRESUMO
A targeted approach has been applied to quantitative analysis of eicosanoids derived from omega-6 fatty acids in serum from individuals diagnosed with coronary artery disease (CAD). The target metabolites were series-2 prostaglandins, thromboxane B2, hydroxyeicosatetraenoic acids, and hydroxyoctadecadienoic acids. The method was based on SPELC-MS/MS in selected reaction monitoring mode for highly selective and sensitive determination of the target eicosanoids. The combination of SPE and LC-MS/MS involved the benefits from both direct analysis of serum without a step for protein precipitation and fully automation of the analysis. The method allowed comparison of omega-6-derived eicosanoids in serum from patients diagnosed with CAD and from control individuals. The effect of treatment with aspirin on the profile of the target compounds was evaluated through its incidence on the different pathways. Finally, the serum levels of the target metabolites in patients diagnosed with CAD were also statistically examined according to the severity of the coronary lesion stratified as stable angina, non-ST-elevation acute coronary syndrome, and acute myocardial infarction.
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Doença da Artéria Coronariana/sangue , Eicosanoides/sangue , Eicosanoides/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Adulto , Idoso , Cromatografia Líquida/métodos , Estudos de Coortes , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodosRESUMO
The aim of this study was to evaluate the relationship between vitamin E status and osteoporosis in early postmenopausal women. Anthropometric data, osteoporosis risk factors, vitamin E serum levels, bone mineral density (BMD) and other serum parameters which may influence bone mineral density in postmenopausal women were analyzed in a cross-sectional study. The association between osteoporosis and age, age of menopause, body mass index, osteocalcin, calcium, vitamin D, vitamin E (measured as 25 hydroxyvitamin D and as α-tocopherol:lipids ratio, respectively), bone alkaline phosphatase, smoking status, leisure physical activity and alcohol intake were modeled by a multivariate logistic regression and multi-linear regression analysis in 232 early postmenopausal women. A lower vitamin E:lipid ratio was associated with osteoporosis in multivariate logistic regression. In a multivariate linear model with BMD of the lumbar spine as a dependent variable, the vitamin E:lipid ratio was clearly related with BMD of the lumbar spine (F ratio = 6.30, p = 0.002). BMD of the lumbar spine was significantly higher in the highest tertile of the vitamin E:lipid ratio than in the lowest tertile. The mean vitamin E:lipid ratio was significantly lower in osteoporotic postmenopausal women (T score ≤-2.5) (3.0 ± 0.6 µmol/mmol) than normal (neither osteoporotic nor osteopenic) postmenopausal women (T score >-1) (3.5 ± 0.7 µmol/mmol) using multivariable-adjusted BMD. These findings highlight that vitamin E may increase BMD in healthy postmenopausal women.
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Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/etiologia , Vitamina E/sangue , Antropometria , Densidade Óssea/fisiologia , Estudos Transversais , Feminino , Colo do Fêmur/patologia , Colo do Fêmur/fisiopatologia , Humanos , Modelos Lineares , Vértebras Lombares/patologia , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Análise MultivariadaRESUMO
An approach for quantitative analysis of two vitamins with different polarities (vitamins D and B9) and their metabolites is presented here. The approach is based on an experimental setup based on hyphenation of an automated workstation for preparation of liquid samples and an LC-MS/MS system with a triple quadrupole mass spectrometer. This configuration enabled development of an orthogonal protocol for sequential SPE retention of analytes with different polarities for subsequent elution and chromatographic separation prior to detection. The resulting method was validated by application to three human biofluids. Estimation of recovery factors in the SPE step led to values from 85.2 to 100% for vitamin D and metabolites and from 93.1 to 100% for vitamin B9 and metabolites (folic acid and folates). The influence of sample matrix variability by analysis of human serum, urine and breast milk was minimized with a complete optimization of the SPE step. The utility of the proposed configuration is shown by the sensitivity and precision of the method, expressed as limits of detection (between 0.2 and 0.30 ng mL(-1) or 4 and 60 pg on-column) and within-laboratory reproducibility (lower than 6.7%, as relative standard deviation). The present application represents an example of determination methods involving targeted analysis of compounds with different polarities using a single aliquot of the sample.
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Ácido Fólico/sangue , Leite Humano/química , Espectrometria de Massas em Tandem/métodos , Vitamina D/sangue , Autoanálise , Cromatografia Líquida/métodos , Feminino , Ácido Fólico/isolamento & purificação , Ácido Fólico/urina , Humanos , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Vitamina D/isolamento & purificação , Vitamina D/urinaRESUMO
BACKGROUND: The progressive transformation of olive growing and the increasing demands for high-quality monovarietal virgin olive oil (VOO) have triggered interest in olive breeding programs, in which the evaluation of the new genotypes is the basis for obtaining new olive cultivars. In this work, the phenolic composition of VOOs from two progenies from crosses between 'Arbequina', 'Arbosana' and 'Sikitita' has been evaluated along two years. RESULTS: A higher degree of variation was observed in segregating population as compared to genitors. The results also showed that the variability within crosses constitutes the major contribution to total variance for all considered parameters (>92% of total sum of squares). All compounds under study were present in oils obtained in both years; however, clear differences in their concentrations were observed between years. CONCLUSION: Olive breeding can indeed provide genotypes that produce oils with improved phenolic profiles as compared to traditional cultivars. In addition, the data showed that selection as a function of tyrosol content could be achieved in only one crop year. Finally, p-coumaric acid was the unique component able to discriminate between both crop years under study.
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Cruzamento , Cruzamentos Genéticos , Variação Genética , Genótipo , Olea/genética , Fenóis/metabolismo , Óleos de Plantas/metabolismo , Olea/metabolismo , Azeite de Oliva , Fenóis/análise , Óleos de Plantas/químicaRESUMO
BACKGROUND: The treatment of ovarian carcinomatosis with cytoreductive surgery and HIPEC is still controversial. The effect and pharmacokinetics of the chemotherapeutics used (especially taxanes) are currently under consideration. METHODS: A phase II, simple blind and randomized controlled trial (NTC02739698) was performed. The trial included 32 patients with primary or recurrent ovarian carcinomatosis undergoing cytoreductive surgery (CRS) and intraoperative intraperitoneal chemotherapy with paclitaxel (PTX): 16 in hyperthermic (42-43 °C) and 16 in normothermic (37 °C) conditions. Tissue, serum and plasma samples were taken in every patient before and after intraperitoneal chemotherapy to measure the concentration of PTX. To analyze the immunohistochemical profile of p53, p27, p21, ki67, PCNA and caspase-3 and the pathological response, a scale of intensity and percentage of expression and a grouped Miller and Payne system were used, respectively. Perioperative characteristics and morbi-mortality were also analyzed. RESULTS: The main characteristics of patients, surgical morbidity, hemotoxicity and nephrotoxicity were similar in both groups. The concentration of paclitaxel in the tissue was higher than that observed in plasma and serum, although no statistically significant differences were found between the two groups. No statistically significant association regarding pathological response and apoptosis (caspase-3) between both groups was proved. There were no statistically significant differences between the normothermic and the hyperthermic group for pathological response and apoptosis. CONCLUSIONS: The use of intraperitoneal PTX has proven adequate pharmacokinetics with reduction of cell cycle and proliferation markers globally without finding statistically significant differences between its administration under hyperthermia versus normothermia conditions.
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A selective and sensitive, fully automated platform for verification and quantitative determination of target peptides in biofluids is proposed and then validated by development of a method for analysis of cathelicidin in human serum. The method is based on the on-line coupling of solid-phase extraction (SPE) and tandem mass spectrometry with direct infusion. Mass spectrometry analysis was carried out by multiple reaction monitoring using three transitions (one for quantitative analysis and two for qualitative analysis), all them confirmed by in silico fragmentation of the target peptide. Samples were prepared in the SPE workstation on a polymeric divinylbenzene resin by preconcentration, deproteinization, and cleanup, removing salts and interferences after direct injection of human serum. The analytical process required 12 min. The limits of detection and quantitation were 2.5 and 8.25 µg/L, respectively (0.20 and 0.66 pg on column). Repeatability and within-laboratory reproducibility were 2.4% and 2.7%, respectively. A dual-cartridge configuration was used to test recovery of cathelicidin in serum, resulting in 80%. Because quantitative retention in the cartridge was assessed, determination of cathelicidin was validated without using synthetic peptides labeled with stable isotopes. The hyphenated system allows full automation, thereby improving reproducibility and accuracy, as demanded by clinical analysis.
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Peptídeos Catiônicos Antimicrobianos/sangue , Automação Laboratorial , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , CatelicidinasRESUMO
The proven endocrine disruption nature of the sunscreen ingredient 2-ethylhexyl 4-(N,N-dimethylamino)benzoate (EDP) calls for research to understand its distribution and bioaccumulation in the human body. A sensitive analytical method to determine EDP and its metabolites in human semen based on online SPE-LC-MS/MS is described. The method has been fully validated and a standard addition calibration has been used for quantification to correct the observed matrix effects. The on-column detection limits of the analytes are between 0.2 and 0.6 ng, depending on the analyte and the sample. The repeatability of the method, expressed as relative standard deviation, was in the range 4.6-9.4%. The method was satisfactorily applied to semen samples from male volunteers who were subjected to single and repeated whole-body applications of an EDP-containing sunscreen product. EDP metabolites were found at different concentrations in semen samples from the repeated application study, thus showing evidences of bioaccumulation in humans.
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Ácido 4-Aminobenzoico/metabolismo , Cromatografia Líquida , Sêmen/química , Protetores Solares/metabolismo , Espectrometria de Massas em Tandem , Ácido 4-Aminobenzoico/análise , Humanos , Masculino , Estrutura Molecular , Reprodutibilidade dos Testes , Sêmen/metabolismo , Extração em Fase Sólida , Protetores Solares/análiseRESUMO
Inflammation is a complex cascade process involved in the pathogenesis of a number of diseases or generated as response to external or internal stimuli. Current research is focused on the development of assays for fast identification and quantitation of inflammation biomarkers. Eicosanoids are the oxidation metabolites of polyunsaturated fatty acids (mainly 20-carbon fatty acids) that play a regulation role in inflammation and, therefore, they have proved to be involved in different pathological states such as cancer, atherosclerosis, arthritis and cardiovascular or immunological diseases. Eicosanoids can be metabolized by different oxygenase enzymes to prostanoids such as prostaglandins and thromboxanes or hydroxyl fatty acids such as hydroxyeicosatetraenoic acids and hydroxyoctadecadienoic acids. A high-throughput automated approach is here presented for direct eicosanoid analysis in biofluids such as human serum and cells culture media. The approach is based on a hyphenated system composed by a solid-phase extraction workstation (Prospekt 2 unit) on-line coupled to a liquid chromatograph-triple quadrupole-tandem mass spectrometer. The detection limits for the target analytes ranged from 0.009 to 204 pg on-column, with precision between 2.65% and 7.33%, expressed as relative standard deviation. Accuracy studies with a dual-cartridge configuration resulted in recoveries between 78.6% and 100%, which validated internally the proposed approach ensuring highly efficient cleanup of proteins and salts. The method is reliable, robust and endowed with a great potential for implementation in clinical and routine laboratories. Analysis of culture media of stem cells stimulated with arachidonic acid was carried out to evaluate its incidence on the eicosanoid profile of the exometabolome.
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Automação/métodos , Eicosanoides/sangue , Eicosanoides/metabolismo , Inflamação/sangue , Inflamação/metabolismo , Metaboloma , Células-Tronco/metabolismo , Ácido Araquidônico/farmacologia , Biomarcadores/análise , Biomarcadores/sangue , Células Cultivadas , Cromatografia Líquida , Humanos , Células-Tronco/efeitos dos fármacos , Espectrometria de Massas em TandemRESUMO
Leaves of olive trees are an abundant raw material in the Mediterranean basin. They contain large amounts of potentially useful phytochemicals and could play beneficial roles in health care. In the present study, the principal bioactive phenols in olive-leaf extracts (OLEs) have been identified and quantified, and their genotoxic/antigenotoxic, cytotoxic and apoptotic effects have been assessed. The Somatic Mutation and Recombination Test (SMART) in wing imaginal discs of Drosophila melanogaster has been performed to test the possible genotoxicity of overall OLE and the individual components oleuropein and luteolin at different concentrations. The same assay was able to detect antigenotoxic activity against hydrogen peroxide as oxidative genotoxicant. None of the extracts/phenols tested showed significant mutagenic activity. This fact, together with the antigenotoxic activity against H(2)O(2) detected for all these extracts/phenols, confirmed the safety of OLE, oleuropein and luteolin in terms of DNA protection. HL60 human promyelocytic leukemia cells were used to assess the cytotoxic effects of the extracts/phenols. OLE, oleuropein and luteolin showed a dose-dependent cytotoxic effect with different IC50 (10µl/ml, 170µM, and 40µM, respectively). DNA fragmentation patterns and cell staining with acridine orange and ethidium bromide indicated that the mechanism for the cytotoxic effect of OLE, oleuropein and luteolin was the apoptotic pathway, with DNA laddering and cytoplasmic and nuclear changes. These results could help explain the mechanism of action that underlies the beneficial effect of OLE, proposed as a nutraceutical in the prevention of human cancer.
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Anticarcinógenos/farmacologia , Antimutagênicos/farmacologia , Dano ao DNA/efeitos dos fármacos , Luteolina/farmacologia , Olea , Óleos de Plantas/farmacologia , Piranos/farmacologia , Apoptose/efeitos dos fármacos , Células HL-60 , Humanos , Glucosídeos Iridoides , Iridoides , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/químicaRESUMO
The most representative indicator of vitamin D status in clinical practice is 25(OH)D3, but new biomarkers could improve the assessment of vitamin D status and metabolism. The objective of this study is to investigate the association of serum vitamin D metabolites and vitamin D metabolite ratios (VMRs) with potentially influential factors in premenopausal women. This is a cross-sectional study based on 1422 women, aged 39-50, recruited from a Madrid Medical Diagnostic Center. Participants answered an epidemiological and a food frequency questionnaire. Serum vitamin D metabolites were determined using an SPE-LC-MS/MS platform. The association between participant's characteristics, vitamin D metabolites, and VMRs was quantified by multiple linear regression models. Mean 25(OH)D3 concentration was 49.2 + 18.9 nmol/L, with greater deficits among obese, nulliparous, dark-skinned women, and with less sun exposure. A lower R2 ratio (1,25(OH)2D3/25(OH)D3) and a higher R4 (24,25(OH)2D3/1,25(OH)2D3) were observed in nulliparous women, with high sun exposure, and those with low caloric intake or high consumption of calcium, vitamin D supplements, or alcohol. Nulliparous women had lower R1 (25(OH)D3/Vit D3) and R3 (24,25(OH)2D3/25(OH)D3), and older women showed lower R3 and R4. Vitamin D status modified the association of the VMRs with seasons. VMRs can be complementary indicators of vitamin D status and its endogenous metabolism, and reveal the influence of certain individual characteristics on the expression of hydroxylase enzymes.
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Metaboloma , Pré-Menopausa/sangue , Vitamina D/sangue , Adulto , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
SCOPE: Wine has shown anticarcinogenic benefits in hepatocarcinoma and polyphenols seem to be responsible for these effects. Wine lees are the sediments produced during fermentation and they endow wine with organoleptic and physicochemical properties. However, the anticarcinogenic role of these compounds is still unknown. Thus, the purpose of this work is to determine the phytochemical profiles of wine lees and then to analyze their anticarcinogenic effect and DNA methylation on a model of hepatocarcinogenesis. METHODS AND RESULTS: The phytochemical composition of lees is determined by the Folin-Ciocalteu method and high-performance liquid chromatography. An in vivo study using a diethyl nitrosamine-hepatocarcinogenesis-induced model is performed to investigate the hepatoprotective properties of different doses of wine lees. For the DNA methylation analysis, a bisulfite-based method is used. Both types of lees mostly contain pyrogallol, gallic, and syringic acid with a high content of catechins in red lees. The carcinogen hypermethylates the Alu-M2 repetitive sequence and white lees decreases the hypermethylation at all tested concentrations. Low concentration of red and white lees and high concentration of white lees significantly improve the hepatocellular architecture and decrease the mitotic index in the murine model. CONCLUSION: These findings suggest that wine lees are promising agents for chemoprevention of hepatocarcinoma.
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Anticarcinógenos/farmacologia , Neoplasias Hepáticas Experimentais/prevenção & controle , Fígado/efeitos dos fármacos , Vinho , Elementos Alu , Animais , Anticarcinógenos/química , Peso Corporal/efeitos dos fármacos , Catecóis/análise , Metilação de DNA/efeitos dos fármacos , Dietilnitrosamina/toxicidade , Fermentação , Ácido Gálico/análogos & derivados , Ácido Gálico/análise , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Pirogalol/análise , Ratos Sprague-Dawley , Vinho/análiseRESUMO
A fast method for the analysis of 10 of the characteristic compounds of the phenolic fraction in grape skin is proposed here. The method is based on a leaching step by superheated ethanol-water at 120 degrees C and 80bar, which enables to maintain the leachant in liquid state and wide the range of leachable compounds (polar, mid-polar and relatively non-polar compounds) by decrease of the dielectric constant; thus, allowing high leaching efficiencies to be achieved in 30min. After leaching, the target analytes were separated by capillary electrophoresis using a 50mM sodium tetraborate with 10% methanol (pH 8.4) solution as background electrolyte. Determination was performed by simultaneous dual diode array absorption and fluorescence detection, the combination of which increased the selectivity of the overall method, particularly interesting taking into account the complexity of the leachate as no additional concentration and/or clean-up steps were required prior to electrophoretic separation, which lasted only 10min. The short time of the electrophoretic step makes it useful as a screening tool of the target analytes in commercial and non-commercial extracts belonging to the pharmaceutical, cosmetic, nutraceutical or food fields.
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Eletroforese Capilar/métodos , Fenóis/análise , Vitis/química , Absorção , Fluorescência , Pele/químicaRESUMO
Hydroxytyrosol and other olive biophenols (OBPs) such as tyrosol, verbascoside, apigenin-7-glucoside, and alpha-taxifolin have been extracted from alperujo by using static-dynamic superheated liquids. Multivariate methodology has been used to carry out a detailed optimization of the extraction. Under the optimal working conditions no further extraction of the target analytes was achieved after 27 min (up to 2800 and 1500 mg/kg of hydroxytyrosol and tyrosol, respectively), so complete removal of them within this interval was assumed. The extract was injected into a chromatograph-photodiode array detector assembly for individual separation-quantification. The efficacy of ethanol/water mixtures to extract OBPs from alperujo has been demonstrated and compared with that of a conventional stirring-based method. These less toxic extractant mixtures are of interest with a view to future human uses of OBPs.
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Temperatura Alta , Resíduos Industriais/análise , Fenóis/isolamento & purificação , Álcool Feniletílico/análogos & derivados , Óleos de Plantas/química , Azeite de Oliva , Álcool Feniletílico/isolamento & purificação , Sensibilidade e EspecificidadeRESUMO
Oleocanthal and oleacein, two key secoiridoid derivatives present in virgin olive oil (VOO), are gaining clinical and nutritional interest thanks to their proved bioactivity; therefore, the determination of both phenols is a growing demanded application to increase the value of VOO. The main problem of previously reported liquid chromatography-based methods for oleocanthal and oleacein measurement is their interaction with water or other polar solvents such as methanol to promote the formation of hemiacetal or acetal derivatives. This interaction can occur during either sample extraction, basically liquid-liquid extraction, and/or chromatographic separation. The aim of this research was to evaluate the suitability of LC-MS/MS for absolute quantitation of oleocanthal and oleacein in VOO. For this purpose, both liquid-liquid extraction and chromatographic separation were studied as potential promoters of acetals and hemiacetals formation from oleocanthal and/or oleacein. The results showed that the use of methanol-water solutions for phenols extraction was not influential on the formation of these artifacts. Acetals and hemiacetals from oleocanthal and/or oleacein were only detected at very low concentrations when methanol gradients under acidic conditions were used for chromatographic separation. With this premise, a protocol based on extraction with acetonitrile and a reverse chromatographic gradient with methanol was established to quantify in absolute terms oleocanthal and oleacein in VOO samples. The resulting protocol was applied to three VOO samples characterized by high, medium, and low levels of these two phenols.
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Aldeídos/análise , Cromatografia Líquida/métodos , Azeite de Oliva/química , Fenóis/análise , Espectrometria de Massas em Tandem/métodos , Aldeídos/isolamento & purificação , Monoterpenos Ciclopentânicos , Extração Líquido-Líquido/métodos , Metanol/química , Fenóis/isolamento & purificaçãoRESUMO
Hydrolysis of oleuropein, the main phenol in olive (Olea europaea L.) leaf extracts, to oleuropein aglycon and other subsequent products in the hydrolytic pathway can be catalyzed by different enzymes. Three of the most used hydrolases were assayed to catalyze the process, and ß-glucosidase from Aspergillus niger was selected. Acceleration of the enzymatic hydrolysis by ultrasound (US) was studied using a Box-Behnken design (duty cycle, amplitude, cycle time) and an oleuropein standard, and the optimum US conditions for achieving maximum yield of oleuropein aglycon were 0.5s/s duty cycle, 50% amplitude and 45s cycle. The method was applied to obtain oleuropein aglycon from commercial and laboratory extracts from olive leaves, which may have a pharmacological use as deduced by its healthy properties. The kinetics of the US-assisted enzymatic hydrolysis was monitored by analysis of the target compounds using liquid chromatography-tandem mass spectrometry.
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Iridoides/química , Olea/química , Extratos Vegetais/química , Folhas de Planta/química , Ultrassom , Aspergillus niger/enzimologia , Cromatografia Líquida , Hidrólise , Glucosídeos Iridoides , Espectrometria de Massas em Tandem , beta-Glucosidase/metabolismoRESUMO
Biological treatments to degrade cyanide are a powerful technology for cyanide removal from industrial wastewaters. It has been previously demonstrated that the alkaliphilic bacterium Pseudomonas pseudoalcaligenes CECT5344 is able to use free cyanide and several metal-cyanide complexes as the sole nitrogen source. In this work, the strain CECT5344 has been used for detoxification of the different chemical forms of cyanide that are present in alkaline wastewaters from the jewelry industry. This liquid residue also contains large concentrations of metals like iron, copper and zinc, making this wastewater even more toxic. To elucidate the molecular mechanisms involved in the bioremediation process, a quantitative proteomic analysis by LC-MS/MS has been carried out in P. pseudoalcaligenes CECT5344 cells grown with the jewelry residue as sole nitrogen source. Different proteins related to cyanide and cyanate assimilation, as well as other proteins involved in transport and resistance to metals were induced by the cyanide-containing jewelry residue. GntR-like regulatory proteins were also induced by this industrial residue and mutational analysis revealed that GntR-like regulatory proteins may play a role in the regulation of cyanide assimilation in P. pseudoalcaligenes CECT5344. The strain CECT5344 has been used in a batch reactor to remove at pH 9 the different forms of cyanide present in industrial wastewaters from the jewelry industry (0.3 g/L, ca. 12 mM total cyanide, including both free cyanide and metal-cyanide complexes). This is the first report describing the biological removal at alkaline pH of such as elevated concentration of cyanide present in a heterogeneous mixture from an industrial source.
Assuntos
Proteínas de Bactérias/metabolismo , Cromatografia Líquida/métodos , Cianetos/toxicidade , Proteômica , Pseudomonas pseudoalcaligenes/efeitos dos fármacos , Espectrometria de Massas em Tandem/métodos , Águas Residuárias/química , Biodegradação Ambiental , Reatores Biológicos , Genes Bacterianos , Pseudomonas pseudoalcaligenes/genética , Pseudomonas pseudoalcaligenes/metabolismoRESUMO
OBJECTIVES: The main aim of this review was to develop a critical discussion of the key role ultrasound (US) can play on the production of active pharmaceutical ingredients (APIs) by discussing the versatile effect this type of energy produces. METHODS: The different crystallization techniques that can be assisted and improved by US are discussed in the light of the available US devices and the effect pursued by application of US energy. Simple and complex analytical methods to monitor API changes are also discussed. KEY FINDINGS: The countless achievements of API US-assisted production are summarized in a table, and outstanding effects such as narrower particle size distribution; decreased particle size, induction time, metastable zone and supersaturation levels; or a solubility increase are critically discussed. CONCLUSIONS: The indisputable advantages of sonocrystallization over other ways of API production have been supported on multiple examples, and pending goals in this field (clarify the effect of US frequency on crystallization, know the mechanism of sonocrystallization, determine potential degradation owing to US energy, avoid calculation of the process yield by determining the concentration of the target drug remaining in the solution, etc.) should be achieved.