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The use of e-cigarettes (ECs) has become increasingly popular worldwide, even though scientific results have not established their safety. Diacetyl (DA) and acetylpropionyl (AP), which can be present in ECs, are linked with lung diseases. Ethyl maltol (EM)-the most commonly used flavoring agent-can be present in toxic concentrations. Until now, there is no methodology for the determination of nicotine, propylene glycol (PG), vegetable glycerin (VG), EM, DA, and acetylpropionyl in e-liquids that can be used as a quality control procedure. Herein, gas chromatography coupled with mass spectrometry (GC-MS) was applied for the development of analytical methodologies for these substances. Two GC-MS methodologies were developed and fully validated, fulfilling the standards for the integration in a routine quality control procedure by manufacturers. As proof of applicability, the methodology was applied for the analysis of several e-liquids. Differences were observed between the labeled and the experimental levels of PG, VG, and nicotine. Three samples contained EM at higher concentrations compared to the other samples, while only one contained DA. These validated methodologies can be used for the quality control analysis of EC liquid samples regarding nicotine, PG, and VG amounts, as well as for the measurement of the EM.
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Sistemas Electrónicos de Liberación de Nicotina , Nicotina , Nicotina/análisis , Cromatografía de Gases y Espectrometría de Masas , Verduras , Diacetil , Propilenglicol/química , Glicerol/químicaRESUMEN
Vaccination is currently the most effective strategy for the mitigation of the COVID-19 pandemic. mRNA vaccines trigger the immune system to produce neutralizing antibodies (NAbs) against SARS-CoV-2 spike proteins. However, the underlying molecular processes affecting immune response after vaccination remain poorly understood, while there is significant heterogeneity in the immune response among individuals. Metabolomics have often been used to provide a deeper understanding of immune cell responses, but in the context of COVID-19 vaccination such data are scarce. Mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR)-based metabolomics were used to provide insights based on the baseline metabolic profile and metabolic alterations induced after mRNA vaccination in paired blood plasma samples collected and analysed before the first and second vaccination and at 3 months post first dose. Based on the level of NAbs just before the second dose, two groups, "low" and "high" responders, were defined. Distinct plasma metabolic profiles were observed in relation to the level of immune response, highlighting the role of amino acid metabolism and the lipid profile as predictive markers of response to vaccination. Furthermore, levels of plasma ceramides along with certain amino acids could emerge as predictive biomarkers of response and severity of inflammation.
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Vacunas contra la COVID-19 , COVID-19 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Biomarcadores , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Humanos , Inmunidad , Metabolómica , Pandemias , Plasma , SARS-CoV-2 , VacunaciónRESUMEN
Oleuropein (OE) is a secoiridoid glycoside occurring mostly in the Oleaceae family and presenting several pharmacological properties, including hypolipidemic and antioxidant properties. Based on these, several dietary supplements containing olive leaf extracts enriched with OE are commercially available in many countries. The current study aimed to examine the effect of supplementation with such an extract on the serum and urine metabolome of young healthy male athletes. For this purpose, applying a randomized, balanced, double-blind study, nine young, healthy males (physical education students) received either a commercially prepared extract or placebo for one week, followed by a two-week washout period; then, they were subsequently dosed with the alternate scheme (crossover design). Urine and serum samples were analyzed using UHPLC-HRMS, followed by evaluation with several multivariate methods of data analysis. The data were interpreted using a multilevel metabolomic approach (multilevel-sPLSDA) as it was found to be the most efficient approach for the study design. Metabolic pathway analysis of the most affected metabolites revealed that tryptophan and acylcarnitine's biochemistries were most influenced. Furthermore, several metabolites connected to indole metabolism were detected, which may indicate enhanced serotonin turnover. Phenylethylamine and related metabolites, as well as estrone, were connected to enhanced performance. In addition, possible changes to the lipidemic profile and the blood and urine redox statuses were investigated.
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Biochemical methylation reactions mediate the transfer of the methyl group regulating vital biochemical reactions implicated in various diseases as well as the methylation of DNA regulating the replication processes occurring in living organisms. As a finite number of methyl carriers are involved in the methyl transfer, their quantification could aid towards the assessment of an organism's methylation potential. An Hydrophilic Interaction Chromatography-Liquid Chromatography Multiple Reaction Monitoring (HILIC-LC-MRM) mass spectrometry (MS) methodology was developed and validated according to Food & Drug Administration (FDA), European Medicines Agency (EMA), and International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) for the simultaneous determination of nine metabolites i.e., B12, folic acid, 5-methyltetrahydrofolate, S-adenosylmethionine, S-adenosylhomocysteine, betaine, phosphocholine, N,N-dimethylglycine, and deoxythymidine monophosphate in human blood plasma. The sample pretreatment was based on a single step Solid-phase extraction (SPE) methodology using C18 cartridges. The methodology was found to accurately quantitate the analytes under investigation according to the corresponding dynamic range proposed in the literature for each analyte. The applicability of the method was assessed using blood donor samples and its applicability demonstrated by the assessment of their basal levels, which were shown to agree with the established basal levels. The methodology can be used for diagnostic purposes as well as for epigenetic screening.
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Colistimethate sodium (CMS) is widely administrated for the treatment of life-threatening infections caused by multidrug-resistant Gram-negative bacteria. Until now, the quality control of CMS formulations has been based on microbiological assays. Herein, an ultra-high-performance liquid chromatography coupled to ultraviolet detector methodology was developed for the quantitation of CMS in injectable formulations. The design of experiments was performed for the optimization of the chromatographic parameters. The chromatographic separation was achieved using a Waters Acquity BEH C8 column employing gradient elution with a mobile phase consisting of (A) 0.001 M aq. ammonium formate and (B) methanol/acetonitrile 79/21 (v/v). CMS compounds were detected at 214 nm. In all, 23 univariate linear-regression models were constructed to measure CMS compounds separately, and one partial least-square regression (PLSr) model constructed to assess the total CMS amount in formulations. The method was validated over the range 100-220 µg mL-1. The developed methodology was employed to analyze several batches of CMS injectable formulations that were also compared against a reference batch employing a Principal Component Analysis, similarity and distance measures, heatmaps and the structural similarity index. The methodology was based on freely available software in order to be readily available for the pharmaceutical industry.
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Colistina/análogos & derivados , Composición de Medicamentos/métodos , Cromatografía Líquida de Alta Presión/métodos , Colistina/administración & dosificación , Colistina/farmacología , Contaminación de Medicamentos/prevención & control , Límite de Detección , Análisis de Componente Principal/métodos , Control de Calidad , Espectrofotometría Ultravioleta/métodosRESUMEN
The metabolite profiling of saffron (Crocus sativus L.) from several countries was measured by using ultra-performance liquid chromatography combined with high resolution mass spectrometry (UPLC-HR MS). Multivariate statistical analysis was employed to distinguish among the several samples of C. sativus L. from Greece, Italy, Morocco, Iran, India, Afghanistan and Kashmir. The results of this study showed that the phytochemical content in the samples of C. sativus L. were obviously diverse in the different countries of origin. The metabolomics approach was deemed to be the most suitable in order to evaluate the enormous array of putative metabolites among the saffron samples studied, and was able to provide a comparative phytochemical screening of these samples. Several markers have been identified that aided the differentiation of a group from its counterparts. This can be important for the selection of the appropriate saffron sample, in view of its health-promoting effect which occurs through the modulation of various biological and physiological processes.
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Crocus/metabolismo , Metaboloma/genética , Fitoquímicos/metabolismo , Extractos Vegetales/química , Biomarcadores , Crocus/química , Crocus/clasificación , Crocus/genética , Cromatografía de Gases y Espectrometría de Masas , Grecia , Humanos , India , Irán , Italia , Metabolómica/métodos , Marruecos , Fitoquímicos/química , Fitoquímicos/clasificación , Extractos Vegetales/clasificación , Extractos Vegetales/metabolismoRESUMEN
Colistimethate (CMS), the prodrug of polymyxin E (colistin), is an antibiotic widely used as a last-line therapy against multidrug resistant Gram-negative bacteria, but little is known about its pharmacokinetics as its administration has stopped as a result of high neuro- and nephro-toxicity. The measurement of CMS levels in patients' biological fluids is of great importance in order to find the optimal dose regimen reducing the drug toxicity. Until now, CMS assay methods are based on the indirect determination after its hydrolysis to colistin (CS). Herein, the aim is to find the optimal conditions for the complete hydrolysis of CMS to CS. The reaction was studied at accelerated conditions: 40 °C, 50 °C, and 60 °C, and the results were evaluated by assessing the Arrhenius equation and computation employing the Tenua software. A validated analytical methodology based on ultra-performance liquid chromatography (UPLC) coupled to a hybrid quadrupole time of flight (QToF) instrument is developed for the simultaneous measurement of CMS and CS. The current methodology resulted in complete hydrolysis, in contrast with the previously reported one.
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Colistina/análogos & derivados , Modelos Biológicos , Profármacos/farmacocinética , Cromatografía Líquida de Alta Presión , Colistina/farmacocinética , Femenino , Humanos , Hidrólisis , Masculino , Espectrometría de Masas , Persona de Mediana EdadRESUMEN
Natural products have played a dominant role in the discovery of lead compounds for the development of drugs aimed at the treatment of human diseases. This electrospray ionization-ion mobility spectrometry-mass spectrometry (ESI-IMS-MS)-based study demonstrates that dietary antioxidants, isolated components from the stigmas of saffron (Crocus sativus L.) may be effective in inhibiting Aß fibrillogenesis, a neuropathological hallmark of Alzheimer's Disease (AD). This study reveals a substantial alteration in the monomer/oligomer distribution of Aß1-40, concomitant with re-direction of fibril formation, induced by the natural product interaction. These alterations on the Aß1-40 aggregation pathway are most prominent for trans-crocin-4 (TC4). Use of ESI-IMS-MS, electron microscopy alongside Thioflavin-T kinetics, and the interpretation of 3-dimensional Driftscope plots indicate a correlation of these monomer/oligomer distribution changes with alterations to Aß1-40 amyloid formation. The latter could prove instrumental in the development of novel aggregation inhibitors for the prevention, or treatment of AD.
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Enfermedad de Alzheimer/tratamiento farmacológico , Antioxidantes/farmacología , Crocus/química , Extractos Vegetales/farmacología , Agregación Patológica de Proteínas/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/ultraestructura , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/uso terapéutico , Carotenoides/farmacología , Humanos , Microscopía Electrónica de Transmisión , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/ultraestructura , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Agregación Patológica de Proteínas/patología , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en TándemRESUMEN
The aim of this study was to determine the cognitive and behavioral effects of extra virgin olive oil total phenolic content (TPC) and Sideritis (SID) extracts in female mice, and identify the associated neurochemical changes in the hippocampus and the prefrontal cortex. All animals received intraperitoneal low or high doses of TPC, SID or vehicle treatment for 7 days and were subjected to the Open Field (OF), Novel Object Recognition (NOR) and Tail Suspension Test (TST). The prefrontal cortex and hippocampus were dissected for analysis of neurotransmitters and aminoacids with high performance liquid chromatography with electrochemical detection (HPLC-ED). Both TPC doses enhanced vertical activity and center entries in the OF, which could indicate an anxiolytic-like effect. In addition, TPC enhanced non-spatial working memory and, in high doses, exerted antidepressant effects. On the other hand, high SID doses remarkably decreased the animals' overall activity. Locomotor and exploratory activities were closely associated with cortical increases in serotonin turnover induced by both treatments. Cognitive performance was linked to glutamate level changes. Furthermore, TPC reduced cortical taurine levels, while SID reduced cortical aspartate levels. TPC seems to have promising cognitive, anxiolytic and antidepressant effects, whereas SID has sedative effects in high doses. Both extracts act in the brain, but their specific actions and properties merit further exploration.
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Conducta Animal/efectos de los fármacos , Aceite de Oliva/química , Fenoles/farmacología , Sideritis/química , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Ratones , Neuroquímica , Fenoles/aislamiento & purificaciónRESUMEN
Colistimethate sodium (CMS) is a widely administrated old-generation prodrug for the treatment of the life-threatening infections caused by multi-resistant Gram-negative bacteria. Until now, the quality control procedure of the CMS commercial products is based on microbiological assays. The aim of the study is the development of a chemical analysis methodology based on liquid chromatography - mass spectrometry (LC-MS) that could be used for the quality control of CMS products. The careful optimization of the LC and QToF-MS parameters was deemed crucial, as CMS is known to be a very complex mixture. Thus, a two stage Design of Experiments (DoE) pipeline has been followed, aiming towards the separation of the mixture components. According to the DoE results, a baseline-resolved chromatogram revealing more than 20 compounds was achieved. The separation was performed using a Waters Acquity BEH C8 column employing gradient elution. The mobile phase consisted of aq. ammonium formate 0.005 M (pH 6) (solvent A) and methanol/acetonitrile 79/21 (v/v) (solvent B). A second optimization experiment for the MS signal was employed in order to achieve maximum sensitivity. The singly charged signals were monitored for the validation in the positive ion mode. The calibration curve range was 50-110 µg mL-1, corresponding to the 80-120% of the nominal CMS amount in the commercial products. Due to the complexity of the CMS chromatograms and the corresponding spectrum of each chromatographic peak, untargeted and targeted approaches were performed employing the MZmine software. Furthermore, apart from the classical univariate statistical analysis, partial least squares regression (PLS-R) model was also employed, as the variables were more than the observations. The developed methodology has been employed to analyze several batches and inconsistences have been discovered.
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Cromatografía Líquida de Alta Presión , Calibración , Cromatografía Liquida , Colistina/análogos & derivados , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de MasasRESUMEN
Hypericum perforatum has plenty of uses in traditional medicine and is the source of top-selling herbal drugs and food supplements. The secondary metabolite chemistry for most of the nearly 500 Hypericum taxa is still unknown, even though they are used interchangeably. In the present study, we characterized four Hypericum populations from Achaia, Greece, belonging to H. perforatum ssp. veronense, H. perfoliatum, H. triquetrifolium, and an uninvestigated taxon, H. empetrifolium ssp. empetrifolium, in terms of their essential oils and polar bioactives in methanolic extracts via GC-MS, LC-HRMS, LC-DAD-MS, and HPLC-DAD. We also performed sequence analysis of nrITS to explore the genetic profile of these taxa and to examine whether their genotype is correlated to the metabolome. Sixty-three non-volatile compounds, phloroglucinols in their majority, and over one hundred (113) volatiles, mostly sesqui- and mono- terpenes, were detected. The concentration of the major polar constituents varied greatly among samples. In particular, phloroglucinols' diversity and abundance in H. empetrifolium ssp. empetrifolium was remarkable. The PCA and Biplot analysis revealed the contribution of each compound to the total chemodiversity and also revealed certain compounds that contribute to the discrimination of the samples. Sequence analysis of nrITS revealed different genetic profiles and markers which can be used for the identification of the four Hypericum taxa. The Mantel test showed a relatively strong correlation between the genetic profile and the volatile compounds and low with the main polar metabolites.
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Hypericum , Grecia , Espectrometría de Masas , Metabolómica , Floroglucinol , Extractos VegetalesRESUMEN
Natural products have served humanity as a valuable source for the discovery and development of therapeutic agents. In addition, these phytochemicals can function as lead compounds for the development of synthetic analogs aimed at treating human diseases. In our aging society, Alzheimer's disease (AD) is the most common cause of dementia, which is characterized by a significant and progressive loss of memory and other cognitive functions. As society demographics change, the predominance of AD and other age-related dementias is increasing, with concurrent financial and societal costs.AD represents one of the most remarkable scientific challenges for drug discovery as the search for effective disease-modifying agents has been unsuccessful. Medicinal plants have been used for their "anti-aging" properties, and cognitive enhancing properties. In the past decades, natural products have been studied for their anti-AD properties, and their potential for developing therapeutic agents against several molecular targets has been evaluated. This insight evaluates the prospects of medicinal plants for providing disease-modifying, as well as disease-preventing, agents for AD.
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Enfermedad de Alzheimer/tratamiento farmacológico , Productos Biológicos/uso terapéutico , Fitoquímicos/uso terapéutico , Productos Biológicos/química , Humanos , Fitoquímicos/químicaRESUMEN
Trans-crocin 4 (TC4) is an important carotenoid constituent of saffron showing potential activity against Alzheimer's Disease (AD) due to its antioxidant and antiamyloidogenic properties. Metabolomics is an emerging scientific field that enhances biomarker discovery and reveals underlying biochemical mechanisms aiming towards the early subclinical diagnosis of diseases. To date, there are no reports on the changes induced to mice plasma metabolome after TC4 administration. We report a novel untargeted UHPLC-ESI HRMS metabolomics strategy to determine the alteration of the metabolic fingerprint following i.p. administration of TC4 in male and female mice. Blood samples from fiftysix mice treated with TC4 as well as from control animals were analyzed with UHPLC-ESI HRMS. Statistical evaluation of the results was achieved by multivariate analysis (MVA), i.e., principal component analysis (PCA), Partial Least Squares-Discriminant Analysis (PLS-DA) in order to discover the variables that contributed to the discrimination between treated and untreated groups which were identified by online database searching (e.g., Metlin, HMDB, KEGG) aided by chemometric processing, e.g., covariance searching etc. Due to the high variability imposed by various factors, e.g., sex of the animals participating in the study, administration dose and time-points of sacrifice, multilevel sparse PLS-DA analysis, e.g., splitting variation to each individual component, has been employed as a more efficient approach for such designs. This methodology allowed the identification of the time sequence of metabolome changes due to the administration of TC4, whereas a sex-related effect on the metabolome is indicated, denoting that the administration in both sexes is indispensable in order to acquire safe conclusions as reliable metabolome pictures. The results demonstrated a number of annotated metabolites playing a potential role in neuroprotection while they are closely related to AD. Moreover, five additional annotated metabolites were involved in the steroid biosynthesis pathway while two of them may be considered as putative neuroprotective agents.
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Carotenoides/farmacocinética , Crocus/química , Metabolómica/métodos , Fármacos Neuroprotectores/farmacocinética , Animales , Vías Biosintéticas/efectos de los fármacos , Carotenoides/administración & dosificación , Cromatografía Líquida de Alta Presión/métodos , Femenino , Inyecciones Intraperitoneales , Masculino , Espectrometría de Masas/métodos , Ratones , Modelos Animales , Fármacos Neuroprotectores/administración & dosificación , Factores Sexuales , Esteroides/biosíntesisRESUMEN
BACKGROUND: The dietary supplementation of livestock with antioxidants to improve the meat quality represents an active research area of high commercial impact. In order to investigate the optimal dosing, analytical methodologies need to be developed in various tissues to evaluate which concentration does remain in the tissue. OBJECTIVE: We aimed to develop and validate a sensitive and specific methodology for the simultaneous quantitative determination of hesperidin, naringin, hesperetin, and naringenin in chicken tissue samples employing ultra-performance LC-tandem MS. METHODS: Lipid extraction using cold chloroform was performed followed by protein precipitation by cold acetone. Chromatography was performed on a C18 column using a ternary gradient of water, acetonitrile, and isopropanol-acetonitrile-acetone (58+40+2, v/v) as the mobile phase. Detection was performed by electrospray ionization in negative ion mode with the selected reaction monitoring technique. RESULTS: Calibration plots exhibited good linearity (r2 > 0.99) over the concentration range from 0.125 to 25 µg/g tissue for the four analytes, and the lower LOQ for the four analytes was 0.125 µg/g tissue. The repeatability as percent relative SD and precision as percent accuracy were <20 and >80%, respectively. CONCLUSIONS: The developed methodology was applied for the quantitative determination of hesperidin, naringin, hesperetin, and naringenin in tissue samples after dietary supplementation with 1.5 g/kg hesperidin and 1.5 g/kg naringin in Ross 308 broiler chickens. HIGHLIGHTS: This is the first methodology to access naringin, naringenin, hesperidin, and hesperetin in chicken tissue. It involved simple sample preparation, and the mass spectrometry based detection ensures high specificity and sensitivity.
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Hesperidina , Espectrometría de Masas en Tándem , Animales , Pollos , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Flavanonas , Reproducibilidad de los ResultadosRESUMEN
Crocus sativus L. natural compounds have been extensively used in traditional medicine for thousands of years. Recent research evidence is now emerging in support of its therapeutic potential for different pathologies including neurodegenerative diseases. Herein, the C. sativus L. natural compounds trans-crocin 4 and trans-crocetin were selected for in depth molecular characterization of their potentially protective effects against Alzheimer's Disease (AD), utilizing two AD neuronal cell culture models (SH-SY5Y overexpressing APP and PC12 expressing hyperphosphorylated tau). Biologically relevant concentrations, ranging from 0.1 µM to 1 mM, applied for 24 h or 72 h, were well tolerated by differentiated wild type SH-SY5Y and PC12 cells. When tested on neuronally differentiated SH-SY5Y-APP both trans-crocin 4 and trans-crocetin had significant effects against amyloidogenic pathways. Trans-crocin 4 significantly decreased of ß-secretase, a key enzyme of the amyloidogenic pathway, and APP-C99, while it decreased γ-secretases that generate toxic beta-amyloid peptides. Similarly, trans-crocetin treatment led to a reduction in ß- and γ-secretases, as well as to accumulation of cellular AßPP. When tested on the neuronally differentiated PC12-htau cells, both compounds proved effective in suppressing the active forms of GSK3ß and ERK1/2 kinases, as well as significantly reducing total tau and tau phosphorylation. Collectively, our data demonstrate a potent effect of trans-crocin 4 and trans-crocetin in suppressing key molecular pathways of AD pathogenesis, rendering them a promising tool in the prevention and potentially the treatment of AD.
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INTRODUCTION: Saffron stigmas from Crocus sativus L. (Iridaceae) are used as a drug in folk medicine, as a food additive and as a dying agent for at least 3500 years. Despite this long-term use the chemical composition of saffron seems still to be not fully known. OBJECTIVE: An analytical strategy for detailed investigations of aqueous saffron extract is developed based on reverse-phase high-performance liquid chromatography electrospray ionisation (HPLC-ESI) multistage mass spectrometry (MSn ) for crocins. METHODS: Commercially available stigmas are analysed by reverse-phase HPLC in combination with ESI/three-dimensional (3D)-ion trap mass spectrometry (MS) and MSn (n = 2 and 3). Sodium chloride is added to the analyte solution ready for injection to promote abundant [M + Na]+ adduct ions of crocins, being ideal precursor ions for low-energy collision-induced dissociation (CID)-MS2/3 . RESULTS: This strategy allows the detailed structural elucidation of known as well as previously unknown crocin derivatives (molecular mass of the aglycon, oligosaccharide chain length and linkage determination). The two isomeric trisaccharide substituents neapolitanose and gentiotriose are distinguished based on linkage-specific cross-ring cleavage for the first time. Furthermore, crocins containing up to six hexose units are also observed. Five novel crocin ester glycosides shifted by a mass difference of -40 Da indicate the presence of the here newly described C17 -aglycon, termed norcrocetin (crocetin = C20 ). CONCLUSIONS: These findings indicate the action of at least two different carotenoid cleavage dioxygenases (CCD2 and tentatively CCD4) during biosynthesis of this new bis-apocarotenoid aglycon (norcrocetin) and the existence of even higher glycosylated crocin derivatives at trace level.
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Carotenoides/análisis , Cromatografía Líquida de Alta Presión/métodos , Crocus/química , Flores/química , Glicósidos/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Carotenoides/química , Ésteres/química , Glicósidos/químicaRESUMEN
Colistin is a multicomponent polypeptide antibiotic consisting mainly of colistin A and colistin B, produced by selected strains of Bacillus polymyxa var. Colistinus. Only recently, the prodrug of colistin, colistimethate sodium, is widely used as last resort antibiotic for infections caused by resistant gram-negative bacteria. Colistin having been discovered several years ago, has not subjected to the drug development and regulatory approval processes that are applied today. However, pharmacological and pharmacokinetic information are necessary for its optimal use thus, during the last decades several studies are carried out in order to shed light on this issue. In the current review, the analytical methodologies of colistin assessment in biological material are summarized and the analytical challenges are critically discussed and critical aspects of the determinations such as the method of detection, the sample pretreatment methodology etc. are compared. Furthermore, critical quality aspects of the assessment methodologies such as the sensitivity of the currently developed methodologies are presented. Lastly, some future trends that should be incorporated in the determination pipeline of modern drugs are suggested.
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Antibacterianos/análisis , Productos Biológicos/análisis , Fraccionamiento Químico/métodos , Colistina/análisis , Animales , Cromatografía/instrumentación , Cromatografía/métodos , Colistina/análogos & derivados , Humanos , Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Paenibacillus polymyxa , Profármacos/análisisRESUMEN
Indirubins represent a group of natural and synthetic products with bio-activities against numerous human cancer cell lines acting by inhibiting protein kinases. The natural sources of indirubins are plants of Isatis sp., Indigofera sp., and Polygonum sp., recombinant bacteria, mammalian urine and some marine mollusks. Specifically, the halogenated derivative 6-bromo indirubin-3'-oxime (6BIO) possesses increased selectivity against GSK-3. However, to our knowledge, no analytical method to determine 6BIO in biological fluids has been developed till now. Therefore, a rapid, sensitive and high throughput UHPLC-MS/MS methods were developed and validated to evaluate the concentrations of 6BIO in mice plasma. Plasma samples were pre-treated by protein precipation using cold mixture of methanol: acetonitrile (9:1, v/v) and separations were carried out on a Hypersil Gold C18 column (50 × 2.1 mm i.d.; 1.9 µm p.s.) using 0.1% acetic acid and methanol as mobile phase at a flow rate of 500 mL/min in a gradient mode. For quantitation, a hybrid LTQ-Orbitrap MS equipped with an electro-spray ionization source was used applying a selected reaction monitoring (SRM) option. The monitored transitions were m/z 354.0 â 324.0 for 6BIO and 297.1 â 282.1 for afromorsin (used as the internal standard) in the negative mode. Following the EMA, ICH and FDA guidelines for validation of analytical procedures, the assay method was fully validated in terms of selectivity, linearity, recovery, matrix effect, accuracy, precision, stability, and robustness. The validated methods were successfully applied to the pharmacokinetic studies of 6BIO following an oral administration to mice at the dose of 50 mg/kg. The results indicated that 6BIO possesses a Tmax of 30 min, a half-life of 1 h, and low plasma bioavailability.
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Antineoplásicos/farmacocinética , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Indoles/farmacocinética , Oximas/farmacocinética , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Evaluación Preclínica de Medicamentos , Indoles/administración & dosificación , Ratones , Oximas/administración & dosificación , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray/instrumentación , Espectrometría de Masas en Tándem/instrumentaciónRESUMEN
This study demonstrates a simple method for one-step isolation of the main secondary metabolites of a hydroalcoholic extract of Crocus sativus stigmas (saffron) using step-gradient centrifugal partition chromatography. The analysis was performed in dual and elution-extrusion mode, using five biphasic systems of the solvents heptane/ethyl acetate/butanol/ethanol/water in ratios of 4:10:0:4:10, 1:13:0:4:10, 1:12:1:4:10, 1:10:3:4:10, and 1:7:6:4:10. Five major crocins, picrocrocin, and crocetin were directly isolated in one step. Scaling up to preparative level, allowed the recovery of significantly high quantities of pure compounds, especially trans-crocin-4, saffron's principal crocin. Comparing dual-mode and elution-extrusion, in dual-mode, the trans-crocin-4 containing fractions were co-eluted with a high amount of free ß-d-glucose. In contrast, absence of free ß-d-glucose was observed in the corresponding trans-crocin-4 fractions obtained by the second method denoting its superiority against dual-mode. Initiating analysis with the 4th solvent-system afforded selective isolation of trans-crocin-4, with reduction in experimental time and solvent consumption. Structure elucidation was performed by nuclear magnetic resonance spectroscopy, liquid chromatography with mass spectrometry, and high-resolution tandem mass spectrometry. The proposed methodology comprises an integrated approach for the purification and characterization of biologically active saffron components in a fast, selective, and environmentally friendly manner.