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1.
Molecules ; 28(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37836667

RESUMO

The fungus Amanita muscaria is universally recognizable for its iconic appearance; it is also widely regarded as poisonous, inedible, and even deadly. In spite of that, there have been documented cases of use of A. muscaria-containing preparations against various diseases, including cancer, to no apparent ill effect. The search for compounds that can be used to treat cancer among various plants and fungi has been intensifying in recent years. In light of this, we describe an HPLC HILIC analytical method for the evaluation of the content of the anticancer compound ergosterol (ERG) and the neuroactive alkaloids ibotenic acid (IBO) and muscimol (MUS) that contribute significantly to the unpleasant physiological syndrome associated with A. muscaria consumption. A 'homemade' A. muscaria tincture made using 80-proof rye vodka as the solvent, an A. muscaria extract made with a standardized water-ethanol solution as the solvent, and fractions obtained from the second extract via liquid-liquid extraction with nonpolar solvents were analyzed. The study also presents the results of capillary zone electrophoresis with contactless conductivity detection and UHPLC-MS/MS analyses of the IBO and MUS content of the two native A. muscaria extracts and an evaluation of the standardized extract's cytotoxic effect against a small panel of lung cell cultures in vitro. Our results show that the standardized extract has a significant cytotoxic effect and does not contain the compounds of interest in any significant quantity.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Ácido Ibotênico/análise , Muscimol/farmacologia , Espectrometria de Massas em Tandem , Linhagem Celular , Solventes , Pulmão/química , Extratos Vegetais/farmacologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-37657402

RESUMO

Liquid chromatography coupled with mass spectrometry is widely used in the field of proteomic analysis after off-line protein digestion. On-line digestion with chromatographic column connected in a series with immobilized enzymatic reactor is not often used approach. In this work we investigated the impact of chromatographic conditions on the protein digestion efficiency. The investigation of trypsin reactor activity was performed by on-line digestion of N-α-benzoyl-L-arginine 4-nitroanilide hydrochloride (BAPNA), followed by separation of the digests on the mixed-mode column. Two trypsin column reactors with the different trypsin coverage on the bridged ethylene hybrid particles were evaluated. To ensure optimal trypsin activity, the separation temperature was set at 37.0 °C and the pH of the mobile phase buffer was maintained at 8.5. The on-line digestion itself ongoing during the initial state of gradient was carried out at a low flow rate using a mobile phase that was free of organic modifiers. Proteins such as cytochrome C, enolase, and myoglobin were successfully digested on-line without prior reduction or alkylation, and the resulting peptides were separated using a mixed-mode column. Additionally, proteins that contain multiple cysteines, such as α-lactalbumin, albumin, ß-lactoglobulin A, and conalbumin, were also successfully digested on-line (after reduction and alkylation). Moreover, trypsin immobilized enzymatic reactors were utilized for over 300 injections without any noticeable loss of digestion activity.


Assuntos
Lactalbumina , Proteômica , Proteólise , Tripsina , Alquilação , Enzimas Imobilizadas
3.
J Chromatogr A ; 1648: 462182, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33979757

RESUMO

In this work, two mixed-mode columns from a different manufacturers and one marketed as a reversed-phase column were characterized and compared in the terms of their interaction abilities, retentivity, peak symmetry, and applicability for peptide separation. All the tested columns contain octadecyl ligand and positively charged modifier, i.e. pyridyl group for the reversed-phase column XSelect CSH C18, quaternary alkylamine for mixed-mode column Atlantis PREMIER BEH C18 AX, and permanently charged moiety (details not available from the manufacturer) for mixed-mode column Luna Omega PS C18. For detailed characterization and comparison of their interaction potential, several approaches were used. First, a simple Walters test was performed to estimate hydrophobic and silanophilic interactions of the tested columns. The highest values of both parameters were observed for column Atlantis PREMIER BEH C18 AX. To investigate the effect of pH and buffer concentration on retention, mobile phases composed of acetonitrile and buffer (ammonium formate, pH 3.0; ammonium acetate pH 4.7 and pH 6.9) in various concentrations (5mM; 10mM; 15mM and 20mM) were used. The analysis of permanently charged compounds was used to describe the electrostatic interaction abilities of the stationary phases. The most significant contribution of electrostatic interactions to the retention was observed for Atlantis PREMIER BEH C18 AX column in the mobile phase with buffer of pH 3.0. A set of ten dipeptides, three pentapeptides and one octapeptide was used to investigate the effects of pH and buffer concentration on retention and peak symmetry. Each of the tested columns provides the optimal peak shape under different buffer pH and concentration. The gradient separation of the 14 tested peptides was used to verify the application potential of the tested columns for peptide separation. The best separation was achieved within 4 minutes on column Atlantis PREMIER BEH C18 AX.


Assuntos
Cromatografia de Fase Reversa/instrumentação , Peptídeos/isolamento & purificação , Soluções Tampão , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
4.
Rheumatol Int ; 39(10): 1749-1757, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31363829

RESUMO

In patients with gout, the serum uric acid (SUA) is usually lower during acute gouty attacks than during intercritical periods. It has been suggested that systemic inflammatory response can cause this phenomenon. The objective is to determine whether therapy with TNF inhibitors (TNFis) affects SUA levels in patients with systemic autoimmune rheumatic diseases (SARDs) and whether SUA changes correlate with pro-inflammatory cytokines or with the oxidative stress marker allantoin. In this study, SUA, CRP, creatinine, MCP-1, IFN-α2, IFN-γ, Il-1ß, IL-6, IL-8, IL-10, IL-12, IL-17a, IL-18, IL-23, IL-33, TNF-α, and allantoin levels were measured prior to and after 3 months of TNFis treatment in patients with SARDs. The values obtained in the biochemical assays were then tested for associations with the patients' demographic and disease-related data. A total of 128 patients (rheumatoid arthritis, n = 44; ankylosing spondylitis, n = 45; psoriatic arthritis, n = 23; and adults with juvenile idiopathic arthritis, n = 16) participated in this study. Among the entire patient population, SUA levels significantly increased 3 months after starting treatment with TNFis (279.5 [84.0] vs. 299.0 [102.0] µmol/l, p < 0.0001), while the levels of CRP, IL-6, IL-8, and MCP-1 significantly decreased. Male sex was the most powerful baseline predictor of ΔSUA in univariate and multivariate models. None of the measured laboratory-based parameters had statistically significant effects on the magnitude of ΔSUA. 3 months of anti-TNF therapy increased the levels of SUA in patients with SARDs, but neither the measured pro-inflammatory cytokines nor the oxidation to allantoin appeared responsible for this effect.


Assuntos
Antirreumáticos/efeitos adversos , Doenças Autoimunes/tratamento farmacológico , Hiperuricemia/induzido quimicamente , Hiperuricemia/diagnóstico , Doenças Reumáticas/tratamento farmacológico , Inibidores do Fator de Necrose Tumoral/efeitos adversos , Ácido Úrico/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alantoína/sangue , Doenças Autoimunes/sangue , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/imunologia , Biomarcadores/sangue , Citocinas/sangue , Feminino , Humanos , Hiperuricemia/sangue , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Sistema de Registros , Doenças Reumáticas/sangue , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/imunologia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima , Adulto Jovem
5.
J Chromatogr A ; 1596: 209-216, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30910386

RESUMO

A series of chiral indole phytoalexins with potential anticancer and antimicrobial activity were enantioseparated in supercritical fluid chromatography. Two polysaccharide-based chiral stationary phases composed of tris-(3,5-dimethylphenylcarbamate) derivatives of amylose or cellulose coated on 2.5 µm silica particles were successfully used. The influences of the polysaccharide backbone, co-solvent type and co-solvent content in the mobile phase on retention, enantioselectivity and enantioresolution of indole phytoalexins were investigated. Fast baseline separations were achieved for 26 from 27 tested compounds. Amylose-based chiral stationary phase provided higher number of baseline resolutions of the indole phytoalexins than the cellulose-based one. However, certain complementary enantioresolution results towards the studied compounds were observed between the investigated columns. The relationship between structure of the indole phytoalexins and their chromatographic behavior in supercritical fluid chromatography was discussed.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia com Fluido Supercrítico , Indóis/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Amilose/química , Celulose/química , Polissacarídeos/química , Dióxido de Silício/química , Solventes/química , Estereoisomerismo , Fitoalexinas
6.
J Chromatogr A ; 1257: 58-65, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-22921504

RESUMO

Hydrophilic interaction liquid chromatography (HILIC) offers very good possibilities for separation of polar compounds as an alternative to reversed phase HPLC where polar compounds are not sufficiently retained. HILIC is becoming more popular for the analysis of biologically interesting (active) analytes. Various stationary phases are commercially available however, development of new materials (sorbents) suitable for HILIC systems still continues. Silica gel columns can be used directly but their modification can improve separation ability of the stationary phases. Cyclofructan-based stationary phases are demonstrated as possible HILIC columns in this work. The effect of silica gel modification by cyclofructan and a derivatized cyclofructan was studied in detail. HILIC separation systems with silica gel, cyclofructan and isopropyl cyclofructan modified silica stationary phases were compared. The detailed study of chromatographic behavior of peptides revealed that multimodal retention mechanism is present in systems with these stationary phases. Mobile phase composition changes the types of interactions and their strengths. It appears that ability to donate protons and dispersion forces are the main interactions that affect retention in HILIC with cyclofructan-based columns while they are less important in separation systems with bare silica stationary phase. Suitability of cyclofructan-based stationary phases in HILIC for separation of pentapeptides and nonapeptides was demonstrated.


Assuntos
Cromatografia Líquida/instrumentação , Frutanos/química , Peptídeos/química , Sílica Gel/química , Cromatografia Líquida/métodos , Interações Hidrofóbicas e Hidrofílicas , Peptídeos/isolamento & purificação
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