RESUMO
The content of chemical constituents in Eugenia uniflora leaf extracts correlates positively with biological activities. The experimental objective was to carry out the phytochemical screening and purification of the major polyphenols from the leaves of E. uniflora. In addition, the anti-Candida activity of the hydroalcoholic extract, fraction, subfractions and polyphenols purified were evaluated. After partitioning of the extract with ethyl acetate, the fractions were chromatographed on Sephadex® LH-20 gel followed by RP-flash chromatography and monitored by TLC and RP-HPLC. The samples were characterized by mass spectrometry (LC-ESI-QTOF-MS2) and subjected to the microdilution method in 96-well plates against strains of C. albicans, C. auris, and C. glabrata. Myricitrin (93.89%; w/w; m/z 463.0876), gallic acid (99.9%; w/w; m/z 169.0142), and ellagic acid (94.2%; w/w; m/z 300.9988) were recovered. The polyphenolic fraction (62.67% (w/w) myricitrin) and the ellagic fraction (67.86% (w/w) ellagic acid) showed the best antifungal performance (MIC between 62.50 and 500 µg/mL), suggesting an association between the majority constituents and the antifungal response of E. uniflora derivatives. However, there is a clear dependence on the presence of the complex chemical mixture. In conclusion, chromatographic strategies were effectively employed to recover the major polyphenols from the leaves of the species.
Assuntos
Antifúngicos , Eugenia , Extratos Vegetais , Folhas de Planta , Polifenóis , Polifenóis/farmacologia , Polifenóis/química , Polifenóis/isolamento & purificação , Eugenia/química , Folhas de Planta/química , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Candida/efeitos dos fármacos , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida de Alta Pressão/métodos , Ácido Gálico/farmacologia , Ácido Gálico/químicaRESUMO
Rotigotine (RTG) is a dopamine agonist used in the treatment of Parkinson's disease. As it is susceptible to oxidation, stability studies must be carefully designed for the identification and characterization of all possible degradation products. Here, RTG degradation was evaluated according to the International Conference on Harmonization guidelines under various stress conditions, including acidic and basic hydrolysis, oxidative, metallic, photolytic, and thermal conditions. Additionally, more severe stress conditions were applied to induce RTG degradation. Significant degradation was only observed under oxidative and photolytic conditions. The samples were analyzed by high performance liquid chromatography coupled to photodiode array detectors, charged aerosol, and high-resolution mass spectrometry. Chromatographic analyses revealed the presence of eight substances related to RTG, four of which were already described and were qualified impurities (impurities B, C, K and E) and four new degradation products (DP-1 - DP-4), whose structures were characterized by high-resolution mass spectrometry through Q-Orbitrap and electrospray ionization. In the stress testing of the active pharmaceutical ingredient in solid form, significant RTG degradation was observed in the presence of the oxidative matrix. The results corroborate the literature that confirm the high susceptibility of RTG to oxidation and the importance of using different detectors to detect degradation products in forced degradation studies.
Assuntos
Estabilidade de Medicamentos , Espectrometria de Massas por Ionização por Electrospray , Tetra-Hidronaftalenos , Tiofenos , Cromatografia Líquida de Alta Pressão/métodos , Tiofenos/química , Tiofenos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Tetra-Hidronaftalenos/química , Tetra-Hidronaftalenos/análise , Oxirredução , Agonistas de Dopamina/análise , Agonistas de Dopamina/química , Hidrólise , Contaminação de Medicamentos/prevenção & controle , FotóliseRESUMO
E. uniflora leaves are a rich source of phenolic compounds with biological activities, including myricitrin. In this study, the chemical profile of nine extracts prepared with leaves collected in three regions (mountain, beach, and mangrove) and at three different times of the day (8 am, 1 pm, and 6 pm) was evaluated from spectra originating from ultra-high resolution mass spectrometry (Fourier transform ion cyclotron resonance, FT-ICR) coupled to electrospray ionisation (ESI). The best time of the day and location for collecting the leaves of E. uniflora used as raw materials for producing extracts and the best ethanol concentration for obtaining an extract more abundant in compounds of interest were verified. Several flavonoids and phenolic acids were detected in their deprotonated form in the regions from m/z 200 to 1200. Myricitrin ([C21H20O12-H]-, m/ztheo 463.08820), its chloride adduct ([C21H20O12+Cl]-, m/ztheo 499.06488), other myricitrin derivatives, and some tannins were the main compounds detected. Considering obtaining an extract rich in phenolic compounds, including myricitrin, the best place and time of the day to collect E. uniflora leaves is in the beach region at 1 pm. In contrast, the best ethanol concentration for extract production is 70 wt%. Therefore, extraction at 96 wt% ethanol is better for obtaining an extract more abundant in phenolic acids, although 70 wt% ethanol also extracted these compounds. FTIR-PCA models were used to check for possible similarities in the data according to collection time of the day and location. These models demonstrated an excellent solution for sample screening.
Assuntos
Fenóis , Extratos Vegetais , Folhas de Planta , Espectrometria de Massas por Ionização por Electrospray , Folhas de Planta/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Extratos Vegetais/química , Fenóis/análise , Fenóis/química , Análise de Componente PrincipalRESUMO
RATIONALE: 4,7-Dichloroquinoline (DCQ) represents a group of synthetic molecules inspired by natural products with important roles in biological and biomedical areas. This work aimed to characterize DCQ and its derivatives by high-resolution electrospray ionization (ESI) mass spectrometry and tandem mass spectrometry (ESI-MS/MS), supported by theoretical calculations. Biological assays were carried out with DCQ and its derivatives to determine LC50 values against Aedes aegypti larvae. METHODS: Five DCQ derivatives were synthesized by using previously described protocols. ESI-MS/MS analyses were carried out with a quadrupole/time-of-flight and ion-trap instrument. The proposed gas-phase protonation sites and fragmentation were supported by density functional theory calculations. The larvicidal tests were performed with the Ae. aegypti Rockefeller strain, and the LC50 values were determined by employing five test concentrations. Larval mortality was determined after treatment for 48 h. RESULTS: DCQ bromides or aldehydes (C-3 or C-8 positions), as well as the trimethylsilyl derivative (C-3 position), were prepared. Detailed ESI-MS/MS data revealed heteroatom elimination through an exception to the even-electron rule, to originate open-shell species. Computational studies were used to define the protonation sites and fragmentation pathways. High activity of DCQ and its derivatives against Ae. aegypti larvae was demonstrated. CONCLUSION: Our results provided a well-founded characterization of the fragmentation reactions of DCQ and its derivatives, which can be useful for complementary studies of the development of a larvicidal product against Ae. aegypti.
Assuntos
Aedes , Espectrometria de Massas por Ionização por Electrospray , Animais , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , LarvaRESUMO
Caffeine is present in a large number of beverages and is an additive used in dietary supplements. Therefore, the concern about its quality and safety for consumers has been increasing and hence requires faster and simpler analytical methods to determine the caffeine amount. The high-throughput analysis is an appropriate solution to pharmaceuticals, bioanalysis, forensic and food laboratory routines. In this sense, Venturi easy ambient sonic-spray ionization mass spectrometry (V-EASI-MS), a specific ambient ionization source, is suitable to enable direct analysis of sample solutions in real time and is appropriate to be coupled to liquid chromatography (LC). The development of an on-line solid phase extraction system coupled to V-EASI-MS optimizes the advantages of LC-MS hyphenation by enhancing the figures of merit of the analytical method according to AOAC guidelines and simultaneously minimizing the runtime analysis to 1.5 min per sample, as well as sample preparation steps and solvent consumption, which is currently a challenge for quantitative applications of ambient ionization MS.
Assuntos
Cafeína , Suplementos Nutricionais , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray , Cafeína/análise , Extração em Fase Sólida/métodos , Suplementos Nutricionais/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Ensaios de Triagem em Larga Escala/métodos , Cromatografia Líquida/métodosRESUMO
Lichens are recognized by their unique compounds and diverse applications in food, medicines, and cosmetics. Using ultra-high pressure liquid chromatography, coupled with a high-resolution mass spectrometer, metabolomic profiling of the lichen Parmotrema perlatum, from a methanolic extract, was performed. Based on characteristic fragmentation patterns, twenty-five lichenic substances were tentatively identified including 5 depsides, 12 depsidones, 2 diphenyl ethers, 1 aromatic considered as possible artifact, 1 dibenzofuran, 1 carbohydrate, 1 organic acid, and 2 undefined compounds. To the best of our knowledge, this is a more complete report of their phytochemistry from P perlatum. Our findings of the P perlatum profile may contribute and complement the current data of the Parmotrema genus.
Assuntos
Lactonas , Líquens , Parmeliaceae , Líquens/química , Espectrometria de Massas por Ionização por Electrospray , Chile , Depsídeos , Cromatografia Líquida de Alta Pressão/métodosRESUMO
Cervical cancer is a specific type of cancer that affects women around the world, with an incidence of 604â thousand new cases per year and 341â thousand deaths. There is a high demand for new effective antineoplastic drugs with few side effects. In this sense, recent research highlights the potential of compounds of natural origin in treating and preventing different types of cancer. Myrciaria glazioviana is a Brazilian native species belonging to the Myrtaceae family, which has previously described biological activities such as antimicrobial, anti-inflammatory, and antioxidant properties. This study aims to evaluate the anticancer activity of the dichloromethane extract (MGD) and ethyl acetate extract (MGA) of M. glazioviana leaves against human cervical cancer cell line (HeLa), as well as to identify their bioactive compounds. Using HPLC-HRESIMS technique, ten compounds were characterized in both samples: quinic acid, ellagic acid, Tri-O-methyl ellagic acid, two derivatives of Tetra-O-methyl flavellagic acid, quercetrin, Di-O-methyl ellagic acid, and three derivatives of pentamethyl coruleoellagic acid. Through MTT assays using HeLa cells and NIH/3T3 cells, it was observed that MGD and MGA were selective against tumor cells, with IC50 values of 24.31 and 12.62â µg/mL, respectively. The samples induced the tumor cell death by apoptosis, as evidenced by the activation of caspases 3/7, cell shrinkage, and pyknotic nuclei. Both samples were also able to inhibit the migration of HeLa cells after 24â hours of treatment, indicating a potential antimetastatic effect. Therefore, the present research highlights the antiproliferative and antimigratory potential of this species against HeLa cells.
Assuntos
Antineoplásicos Fitogênicos , Apoptose , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Myrtaceae , Extratos Vegetais , Neoplasias do Colo do Útero , Humanos , Células HeLa , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Myrtaceae/química , Cromatografia Líquida de Alta Pressão , Apoptose/efeitos dos fármacos , Feminino , Relação Dose-Resposta a Droga , Camundongos , Folhas de Planta/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Steroids that take part in the pathways of human steroidogenesis are involved in many biological mechanisms where they interact with calcium. In the present work, the binding selectivities and affinities for calcium of progestagens, mineralocorticoids, androstagens, and estrogens were studied by Electrospray Ionization-Mass Spectrometry (ESI-MS). The adduct profile of each steroid was characterized by high resolution and tandem mass spectrometry. The relative stability of the most important adducts was studied by threshold collision induced dissociation, E1/2. Doubly-charged steroid-calcium complexes [nM + Ca]2+ with n = 1-6 were predominant in the mass spectra. The adduct [5M + Ca]2+ was the base peak for most 3-keto-steroids, while ligands bearing hindered ketones or α-hydroxy-ketones also yielded [nM + Ca + mH2O]2+ with n = 3-4 and m = 0-1. Principal component analysis allowed us to spot the main differences and similarities in the binding behavior of these steroids. The isomers testosterone and dehydroepiandrosterone, androstanolone and epiandrosterone, and 17-α-hydroxyprogesterone and 11-deoxycorticosterone showed remarkable differences in their adduct profiles. Computational modeling of representative adducts was performed by density functional theory methods. The possible binding modes at low and high numbers of steroid ligands were determined by calcium Gas Phase Affinity, and through modeling of the complexes and comparison of their relative stabilities, in agreement with the experimental results.
Assuntos
Cálcio , Espectrometria de Massas por Ionização por Electrospray , Humanos , Cálcio/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Esteroides , CetonasRESUMO
In this study, we specifically focused on the crude methanolic leaf extract of Byrsonima coccolobifolia, investigating its antifungal potential against human pathogenic fungi and its antiviral activity against COVID-19. Through the use of high-performance liquid chromatography coupled with electrospray ionization ion trap tandem mass spectrometry, direct infusion electrospray ionization ion trap tandem mass spectrometry, and chromatographic dereplication procedures, we identified galloyl quinic acid derivatives, catechin derivatives, proanthocyanidins, and flavonoid glycosides. The broth dilution assay revealed that the methanolic leaf extract of B. coccolobifolia exhibits antifungal activity against Cryptococcus neoformans (IC50 = 4 µg/mL). Additionally, docking studies were conducted to elucidate the interactions between the identified compounds and the central residues at the binding site of biological targets associated with COVID-19. Furthermore, the extract demonstrated an in vitro half-maximum effective concentration (EC50 = 7 µg/mL) and exhibited significant selectivity (>90%) toward SARS-CoV-2.
Assuntos
COVID-19 , Extratos Vegetais , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antifúngicos , Estrutura Molecular , SARS-CoV-2 , Espectrometria de Massas por Ionização por Electrospray/métodos , Metanol , Antivirais/farmacologia , Cromatografia Líquida de Alta Pressão/métodosRESUMO
INTRODUCTION: The genus Omphalotus, in particular the "Jack-O'Lantern mushrooms" Omphalotus illudens and Omphalotus olearius, are famous for the production of the DNA-alkylating illudins. A lesser-known species, Omphalotus mexicanus, native to Central America, also produces cytotoxic illudins S and M, but its minor secondary metabolites are yet to be investigated. OBJECTIVE: To identify, isolate, and elucidate the structure of novel secondary metabolites of the illudin family in mycelial extracts of O. mexicanus from submerse cultivation. METHODOLOGY: A fermentation of the fungus in 15 L stirred tank bioreactors is described. Mycelial extracts were separated using a combination of flash chromatography with preparative RP-C18 high-performance liquid chromatography (HPLC). Analysis of metabolites was done using an ultrahigh-performance liquid chromatography ultraviolet diode array detector (UPLC-UV-DAD) system coupled to an electrospray ionisation quadrupole time-of-flight (ESI-QTOF) mass spectrometer. Structures were elucidated using one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance spectroscopy (NMR) techniques followed by comparison of experimental and simulated electronic circular dichroism (ECD) spectra to determine absolute configurations. RESULTS: Two novel illudin derivatives, for which we propose the names omphaderol (1) and illudaneol B (2), as well as illudaneol (3) and the unusual cyclobutylcyclopentane illudosin (4), were isolated from the mycelia and characterised. CONCLUSION: Particularly the illudaneol derivatives with their high titers may be potential building blocks for an alternative semisynthetic route to new illudin derivatives with improved medical properties. Additionally, the findings improve the knowledge of minor illudin compounds in the mycelial extract of this fungus and may be of significance for future biosynthetic studies of the illudins.