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1.
Antioxidants (Basel) ; 12(12)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38136159

RESUMO

Plant products, especially medicinal herbs and spices, have been used for centuries as a remedy to support human health and improve the flavor of food. Therefore, the purpose of this study was to identify plant species distinguished by their high content of phenolic compounds and high antioxidant activity using advanced multivariate statistical techniques such as Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). To realize the purpose of the study, the total phenolic (TPC) and flavonoids (FC) content, antioxidant activity (TAC) and Fe(II) ion chelating capacity (FIC) of medicinal herbs and spices from plants belonging to three botanical families, Lamiaceae, Apiaceae and Asteraceae were determined. The interpretation of the obtained data revealed that the studied samples are localized in the PCA and HCA plots according to their TPC, FC, TAC and FIC values. Chemometric analysis confirmed that medicinal herbs and spices from plants belonging to the Lamiaceae family are richer sources of phenolic compounds and exhibit stronger antioxidant activity than those raw materials from plants in the Apiaceae family. In addition, no significant differences were found in terms of TPC, FC, TAC and FIC values between medicinal herbs and spices from the same plant species, i.e., oregano (Origanum vulgare), common thyme (Thymus vulgaris), rosemary (Rosmarinus officinalis), caraway (Carum carvi) and lovage (Levisticum officinale). A close relationship between antioxidant properties and contents of phenolic compounds was also confirmed.

2.
Pharmaceutics ; 15(6)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37376045

RESUMO

Reliable interpretation of the changes occurring in the samples during their heating is ensured by using more than one measurement technique. This is related to the necessity of eliminating the uncertainty resulting from the interpretation of data obtained by two or more single techniques based on the study of several samples analyzed at different times. Accordingly, the purpose of this paper is to briefly characterize thermal analysis techniques coupled to non-thermal techniques, most often spectroscopic or chromatographic. The design of coupled thermogravimetry (TG) with Fourier transform infrared spectroscopy (FTIR), TG with mass spectrometry (MS) and TG with gas chromatography/mass spectrometry (GC/MS) systems and the principles of measurement are discussed. Using medicinal substances as examples, the key importance of coupled techniques in pharmaceutical technology is pointed out. They make it possible not only to know precisely the behavior of medicinal substances during heating and to identify volatile degradation products, but also to determine the mechanism of thermal decomposition. The data obtained make it possible to predict the behavior of medicinal substances during the manufacture of pharmaceutical preparations and determine their shelf life and storage conditions. Additionally, characterized are design solutions that support the interpretation of differential scanning calorimetry (DSC) curves based on observation of the samples during heating or based on simultaneous registration of FTIR spectra and X-ray diffractograms (XRD). This is important because DSC is an inherently non-specific technique. For this reason, individual phase transitions cannot be distinguished from each other based on DSC curves, and supporting techniques are required to interpret them correctly.

3.
Biomedicines ; 11(3)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36979687

RESUMO

The determination of antidepressant drugs and their metabolites in the body, mainly in the blood, allows for the monitoring of drug levels and their metabolism, helps identify drug interactions, and reduces the likelihood of increased side effects. Due to numerous inconveniences associated with collecting blood in patients, therapeutic drug monitoring (TDM) based on saliva sampling could significantly improve patient comfort. Therefore, the aim of this study was to develop a method for the simultaneous determination of selected antidepressants (amitriptyline, mianserin, duloxetine, mirtazapine, sertraline, citalopram, and venlafaxine) and their metabolites (N-desmethylmirtazapine, norsertraline, N-desmethylcitalopram, O-desmethylvenlafaxine) in human saliva using supported liquid extraction (SLE). Chlordiazepoxide was used as an internal standard. UHPLC coupled with DAD detection was used for the determinations. The proposed method was validated by determining its linearity for saliva concentrations in the range 10-1000 ng/mL. For all the analyzed compounds, a linear relationship between the analytical signal and analyte concentration was obtained (R2 > 0.99), with the intra- and inter-day precisions expressed as a coefficient of variation (% CV) below 15% in all tested cases. The study showed the usefulness of the proposed method for the isolation of antidepressant drugs and their metabolites in saliva patients' samples.

4.
Int J Mol Sci ; 23(19)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36233346

RESUMO

Since the formation of organic salts can improve the solubility, bioavailability, and stability of active pharmaceutical ingredients, the aim of this work was to prepare an organic salt of chlordiazepoxide with saccharin. To achieve this goal, the saccharin salt of chlordiazepoxide was obtained from a physical mixture of both components by grinding them with a small volume of solvent and by crystallizing them with complete evaporation of the solvent. The resulting salt was examined by methods such as Powder X-ray Diffraction (PXRD), Single Crystal X-ray Diffraction (SCXRD), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FT-IR), and Raman spectroscopy. The results of the studies proved that saccharin salt of chlordiazepoxide crystallizes in the orthorhombic Pbca space group with one chlordiazepoxide cation and one saccharin anion in the asymmetric unit. In the crystal of the title compound, the chlordiazepoxide cation and the saccharin anion interact through strong N-H···O hydrogen bonds and weak C-H···O hydrogen bonds. The disappearance of the N-H band in the FT-IR spectrum of saccharin may indicate a shift of this proton towards chlordiazepoxide, while the disappearance of the aromatic bond band in the chlordiazepoxide ring in the Raman spectrum may suggest the formation of intermolecular hydrogen bonds between chlordiazepoxide molecules. The melting point of the salts differs from that of the starting compounds. Thermal decomposition of the salt begins above 200 °C and shows at least two overlapping stages of mass loss. In summary, the results of the research showed that the crystalline salt of the saccharin and chlordiazepoxide can be obtained by various methods: grinding with the addition of acetonitrile and crystallization from acetonitrile or a mixture of methanol with methylene chloride.


Assuntos
Clordiazepóxido , Sacarina , Acetonitrilas , Varredura Diferencial de Calorimetria , Metanol , Cloreto de Metileno , Pós , Prótons , Sais/química , Solubilidade , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
5.
Molecules ; 27(13)2022 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-35807528

RESUMO

Pharmaceutical excipients should not interact with active substances, however, in practice, they sometimes do it, affecting the efficacy, stability and safety of drugs. Thus, interactions between active substances and excipients are not desirable. For this reason, two component mixtures of oral antidiabetic drug linagliptin (LINA) with four excipients of different reactivity, i.e., lactose (LAC), mannitol (MAN), magnesium stearate (MGS) and polyvinylpyrrolidone (PVP), were prepared in a solid state. A high temperature and a high humidity of 60 °C and 70% RH, respectively, were applied as stressors in order to accelerate the potential interactions between LINA and excipients. Differential scanning calorimetry (DSC) as well as Fourier transform infrared (FT-IR) and near infrared (NIR) spectroscopy were used to estimate the changes due to potential interactions. In addition, chemometric computation of the data with principal component analysis (PCA) and hierarchical cluster analysis (HCA) was applied to adequately interpret the findings. Of the excipients used in the present experiment, all of them were not inert in relation to LINA. Some of the interactions were shown without any stressing, whereas others were observed under high-temperature/high-humidity conditions. Thus, it could be concluded that selection of appropriate excipients for LINA is very important question to minimize its degradation, especially when new types of formulations with LINA are being developed and manufactured.


Assuntos
Excipientes , Linagliptina , Varredura Diferencial de Calorimetria , Quimiometria , Análise por Conglomerados , Estabilidade de Medicamentos , Excipientes/química , Análise de Fourier , Humanos , Hipoglicemiantes , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
6.
Foods ; 11(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35267300

RESUMO

Background: Medicinal plants are often used in the treatment of diabetes mellitus, although knowledge about their mode of action and the substances responsible for their antidiabetic potential is limited. It is well known that some trace elements play a role in glucose metabolism and insulin action. Thus, a particular trace elements profile could be associated with the antidiabetic properties observed for some medicinal plants. Methods: Infusions (n = 102) prepared from commercial herbal products (n = 34) containing medicinal plants indicated for the treatment of diabetes (n = 16 different plant species) and infusions (n = 60) prepared from commercial herbal products (n = 20) containing medicinal plants without such an indication (n = 7 different plant species) were analyzed by ICP-MS for their trace elements content. Results: In both groups, results varied significantly between different medicinal plants and also between different origins (brands) of the same medicinal plant. Significant differences (p < 0.05) between the two groups were found for nine elements, including four trace elements related to glucose metabolism (Mn, B, V, and Se), but with lower median contents in the group of medicinal plants for diabetes. Conclusions: Except for some particular species (e.g., Myrtilli folium) in which the trace element Mn may play a role in its antidiabetic effect, globally, a direct association between the claimed antidiabetic properties and a specific trace element profile of the studied medicinal plants was not evident.

7.
J Clin Med ; 10(21)2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34768724

RESUMO

Cortisol-the most important steroid hormone with a significant effect on body metabolism-strongly affects peripheral tissues and the central nervous system. Fluctuations in cortisol secretion often accompany psychiatric disorders, and normalization of its levels correlates with improvement in the patient's health. This indicates that cortisol may be useful as a biological marker that can help determine the likelihood of mental illness, its impending onset, and the severity of symptoms, which is especially important in the face of the increasing prevalence of mental disorders, including those associated with social isolation and anxiety during the COVID-19 pandemic. This publication reviews recent reports on cortisol levels in healthy participants and shows the current state of knowledge on changes in the levels of this hormone in people at risk for depression, bipolar disorder, and psychosis. It shows how people with psychiatric disorders react to stressful situations and how the applied therapies affect cortisol secretion. The influence of antidepressants and antipsychotics on cortisol levels in healthy people and those with mental disorders is also described. Finally, it reviews publications on the patterns of cortisol secretion in patients in remission.

8.
Pharmaceutics ; 13(11)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34834251

RESUMO

As amorphization may improve the solubility and bioavailability of a drug substance, the aim of this work was to assess to what extent the crystallinity of caffeine (CAF) and theophylline (TF) can be reduced by homogenization with a polymeric excipient. To realize this purpose, the physical mixtures of both methylxanthines with hydroxypropyl methylcellulose (HPMC) were examined using differential scanning calorimetry (DSC), hot-stage microscopy (HSM), Fourier-transform infrared (FTIR) and Raman spectroscopy. Moreover, phase diagrams for the physical mixtures were calculated using theoretical data. Results of DSC experiments suggested that both CAF and TF underwent amorphization, which indicated proportional loss of crystallinity for methylxanthines in the mixtures with HPMC. Additionally, HSM revealed that no other crystalline or amorphous phases were created other than those observed for CAF and TF. FTIR and Raman spectra displayed all the bands characteristic for methylxanthines in mixtures with HPMC, thereby excluding changes in their chemical structures. However, changes to the intensity of the bands created by hydrogen bonds imply the formation of hydrogen bonding in the carbonyl group of methylxanthines and the methyl polymer group. This is consistent with data obtained using principal component analysis. The findings of these studies revealed the quantities of methylxanthines which may be dissolved in the polymer at a given temperature and the composition at which methylxanthines and polymer are sufficiently miscible to form a solid solution.

9.
AAPS PharmSciTech ; 23(1): 3, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34799781

RESUMO

An important challenge to overcome in the solid dosage forms technology is the selection of the most biopharmaceutically efficient polymeric excipients. The excipients can be selected, among others, by compatibility studies since incompatibilities between ingredients of the drug formulations adversely affect their bioavailability, stability, efficacy, and safety. Therefore, new, fast, and reliable methods for detecting incompatibility are constantly being sought. Hence, the purpose of this work was to assess the usefulness of a heating, cooling, and reheating differential scanning calorimetry (DSC) program for detecting potential incompatibilities between atenolol, an active pharmaceutical ingredient (API), and polymeric excipients. Hot-stage microscopy (HSM), Fourier transform infrared (FTIR) spectroscopy, and powder X-ray diffraction (PXRD) were used as supporting techniques. Additionally, principal component analysis (PCA) and hierarchical cluster analysis (HCA) served as tools to support the interpretation of the data acquired from the DSC curves and FTIR spectra. As the alterations in the shape of the DSC peak of atenolol which are indicative of incompatibility are visible only on the cooling and reheating curves of the mixtures, the DSC heating-cooling-reheating program was found to be very useful for identifying potential incompatibilities in the binary mixtures of atenolol and polymeric excipients. The melting and recrystallization of atenolol alone and in its mixtures were also confirmed by HSM, while FTIR displayed changes in the spectra of mixtures due to incompatibility. These studies revealed that atenolol is incompatible with hydroxyethylcellulose, hypromellose, and methylcellulose. PXRD measurements at room temperature revealed that the crystallinity of atenolol did not change in these mixtures. However, its crystallinity was reduced in the mixtures previously heated up to 155 °C and then cooled to 25 °C.


Assuntos
Atenolol , Excipientes , Varredura Diferencial de Calorimetria , Análise por Conglomerados , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Plant Foods Hum Nutr ; 76(4): 458-465, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34570290

RESUMO

Bioactivity of mulberry has been widely described, but mostly related to its fruits, while studies with leaves are scarce. Herein, in this study leaves of two mulberry species (Morus alba L. and Morus nigra L.) were characterized, compared, and evaluated in terms of their phenolic composition and antioxidant activity. Aiming to valorize mulberry leaves extracts which can be included in modern diet four different extracts (infusions, decoctions, tinctures and hydromethanolic) were examined. The chemical characterization was done by quantifying total phenolics (TPC), flavonoids (TFC) and phenolic acids (TPAC) content, L( +)ascorbic acid (ASA) and individual phenolic compounds in the extracts by HPLC technique. Moreover, DPPH and FRAP assays were used to assess the antioxidant activity of white and black mulberry leaves. Findings of these studies revealed that black mulberry leaves were richer in TFC and TPAC, while white mulberry leaves contained higher levels of individual phenolic compounds in water extracts. Gallic acid was found in the highest concentrations in two mulberry leave extracts. Correlation analysis showed strong relationships between antioxidant activity and TPC and TFC. This fact suggests the crucial role of phenolic compounds as antioxidant agents in white and black mulberry leaves. The results obtained in this study demonstrate that leaves of both white and black mulberry can be used as a valuable source of phenolic compounds with bioactive potential, which can be applied in the food sector, as foods and as promising source of natural ingredients.


Assuntos
Morus , Antioxidantes , Fenóis , Extratos Vegetais/farmacologia , Folhas de Planta
11.
Cardiol J ; 28(4): 534-542, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-30912576

RESUMO

BACKGROUND: Oxidative stress and dyslipidemia play a critical role in the development of cardiovascular disease (CVD). Regular intake of polyphenol-rich diets is associated with a reduced risk of CVDs. METHODS: The present study was a pilot study with 24 healthy volunteers and was designed to determine if a 12-week administration of Cistus incanus herbal tea, containing phenolic acids and flavonoids, reduces cardiovascular risk factors including oxidative stress and dyslipidemia in healthy adults. Phenolic compounds profile and antibacterial activity of Cistus incanus infusion were also measured. RESULTS: Herbal infusion led to improvement in lipid profile by increase (D4%, p = 0.033) high-density lipoprotein cholesterol concentration and decrease triglyceride (D14%, p = 0.013) concentrations. In addition, the Cistus incanus diet was associated with decreased serum concentrations of malondialdehyde (D16%, p < 0.01) and advanced oxidation protein products (D18%, p < 0.001). CONCLUSIONS: Cistus incanus administration decreases cardiovascular risk factors including oxidative stress and dyslipidemia and this action supports the idea of using Cistus incanus tea on a daily basis as an effective dietary component for prevention of atherosclerotic CVD.


Assuntos
Cistus , Chás de Ervas , Adulto , Suplementos Nutricionais , Humanos , Lipídeos , Estresse Oxidativo , Projetos Piloto , Extratos Vegetais/farmacologia
12.
Molecules ; 25(22)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198171

RESUMO

Rosa canina L. (dog rose) is a rich source of phenolic compounds that offer great hope for the prevention of chronic human diseases. Herein, wild and commercial samples of dog rose were chemically characterized with respect to their phenolic composition by liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI/MS). Furthermore, in vitro antioxidant properties and antibacterial activity of dog rose fruits and leaves hydromethanolic extracts and infusions were also evaluated. The results revealed that wild and commercial fruits of dog rose are similar in terms of l(+)-ascorbic acid, total phenolics (TPC), total flavonoids (TFC) and total phenolic acids (TPAC) content, individual phenolic constituents and antioxidant activity. Moreover, the fruits had lower levels of phenolic compounds and also revealed lower biological activity than the leaves. On the other hands, the highest content of TPC, TFC, TPAC, individual phenolic constituents, DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity and FRAP (ferric reducing antioxidant power) were found in the leaf's infusions. They were also the only ones to show antibacterial activity. Overall, these finding confirmed usefulness of R. canina L. leaves and fruits as a rich source of bioactive phenolic compounds with potential use in food, pharmaceutical, and cosmetic industries.


Assuntos
Antioxidantes/química , Frutas/química , Fenóis/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Rosa/química , Compostos de Bifenilo/química , Cromatografia Líquida , Cosméticos , Escherichia coli/efeitos dos fármacos , Flavonoides/química , Hidroxibenzoatos/química , Testes de Sensibilidade Microbiana , Picratos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Espectrometria de Massas por Ionização por Electrospray , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos
13.
J Clin Med ; 9(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066306

RESUMO

Although blood is the basic test material to monitor levels of antipsychotic drugs in a person's system, saliva could serve as a more convenient test material. Therefore, the aim of this novel study was to determine the correlations between the salivary levels of olanzapine and quetiapine (and their metabolites: N-demethyl olanzapine and norquetiapine) and the patient's sex and age, dose level, and the time of sampling. The study involved two groups of patients: 21 female patients starting treatment immediately after being admitted to the hospital and 36 male and female nursing home residents, long-time users of the studied drugs. Women had lower levels of the tested analytes than men. Quetiapine levels in the saliva of people starting the treatment showed a positive correlation with the age of the patients and a strong positive correlation with the dose level. The saliva levels of olanzapine showed a strong correlation with its metabolite in patients who had recently started treatment. Among long-time users of this drug, salivary levels differed significantly before and after administration. In conclusion, the results indicate that there is a possibility of using saliva as a material for monitoring quetiapine or olanzapine concentrations, especially in people starting treatment.

14.
Pharmaceutics ; 12(7)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32659986

RESUMO

The low water solubility of benzodiazepines seriously affects their bioavailability and, in consequence, their biological activity. Since co-crystallization has been found to be a promising way to modify undesirable properties in active pharmaceutical ingredients, the objective of this study was to prepare co-crystals of two benzodiazepines, chlordiazepoxide and lorazepam. Using different co-crystallization procedures, slurry evaporation and liquid-assisted grinding, co-crystals of chlordiazepoxide with p-aminobenzoic acid and lorazepam with nicotinamide were prepared for the first time. Confirmation that co-crystals were obtained was achieved through a comparison of the data acquired for both co-crystals using differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Fourier-transform infrared (FTIR) and Raman spectroscopy, with comparisons acquired for the physical mixtures of both benzodiazepines and coformers. The compatibility of PXRD patterns of both benzodiazepines co-crystals with those contained in the base Powder Diffraction File (PDF-4+) suggests that new crystal structures were indeed created under the co-crystallization procedure. Single-crystal X-ray diffraction revealed that a chlordiazepoxide co-crystal with p-aminobenzoic acid and a lorazepam co-crystal with nicotinamide crystallized in the monoclinic P21/n and P21/c space group, respectively, with one molecule of benzodiazepine and one of coformer in the asymmetric unit. FTIR and Raman spectroscopy corroborated that benzodiazepine and coformer are linked by a hydrogen bond without proton exchange. Furthermore, a DSC study revealed that single endothermic DSC peaks assigned to the melting of co-crystals differ slightly depending on the co-crystallization procedures and solvent used, as well as differing from those of starting components.

15.
J Clin Med ; 9(4)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230768

RESUMO

Saliva is a valuable diagnostic material that, in some cases, may replace blood. However, because of its different composition, its use requires the development of new, or the modification of existing, extraction procedures. Therefore, the aim of the study was to develop a method of saliva purification that would enable the determination of carbamazepine and its metabolite, carbamazepine-10,11 epoxide. When comparing two methods of sample purification (Solid Phase Extration (SPE) and deproteinization), it was found that the second method yielded more favorable results. A 1% formic acid solution in acetonitrile was used for extraction. The samples were shaken and centrifuged, and the supernatant obtained was evaporated and dissolved in a mobile phase, then chromatographically analyzed. The developed method was validated by determining its linearity in the range of 10-5000 ng/mL for both analytes. Intra- and inter-day precision did not exceed 14%. In order to check the usefulness of the method, both analytes were determined in the saliva samples from 20 patients treated with carbamazepine. The content of both analytes was detected and determined in all of the tested samples of saliva. It was found that the method developed is rapid, sensitive, reliable, and can be used to monitor the concentration of carbamazepine and metabolite in patients' saliva.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 234: 118242, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32179462

RESUMO

Co-crystals, which are defined as "solids that are crystalline materials composed of two or more molecules in the same crystal lattice" have recently been the focus of increased interest in the pharmaceutical industry since co-crystallization can improve unfavorable physicochemical properties of active pharmaceutical ingredients. Thus, the quest for new co-crystal screening methods has become an issue of importance. The aim of this work was, therefore, to show to what extent expanded methodology based on FTIR and Raman spectroscopy supported by the DSC method can be used as a reliable tool to screen co-crystallization. Because co-crystals of benzodiazepines had not yet been obtained, a set of 72 binary mixtures composed of eight 1,4-benzodiazepine derivatives and nine coformers were used as model substances. Potential co-crystals were prepared in solid-state by liquid-assisted grinding procedure. The characteristic FTIR and Raman bands which reflect hydrogen bond formation between benzodiazepine and coformer were used as proof of co-crystal creation. DSC was used as a supporting tool to reflect the phase transitions which occur during co-crystallization. As a result of the study, four potential co-crystals can be selected: lorazepam with nicotinamide, chlordiazepoxide with p-aminobenzoic and saccharin, and estazolam with fumaric acid. The detailed spectral and thermal characteristics of these systems are presented in this work. Thus, the proposed methodology of co-crystal screening based on FTIR and Raman data supported by the DSC examination of phase transitions facilitates the screening and detection of benzodiazepine co-crystal prepared by short time components ground with a slight additional volume of solvent.


Assuntos
Benzodiazepinas/química , Varredura Diferencial de Calorimetria , Análise Espectral Raman , Calibragem , Cristalização , Niacinamida/química , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Nat Prod Res ; 34(21): 3154-3157, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31088303

RESUMO

A simple and reliable HPLC method was developed and validated for the quality consistency evaluation of Coffea arabica commercial samples through establishing chromatographic fingerprint and simultaneous determination of bioactive constituents. In the HPLC fingerprint, thirteen common peaks were selected to assess the similarities of coffee samples of different geographical origin. A similarity analysis showed values from 0.434 to 0.950 for the analyzed samples, while quantitation of selected bioactive compounds revealed the highest content of caffeine and the lowest of p-coumaric acid and theobromine in coffee samples. Since phenolic compounds and alkaloids are commonly recognized as natural antioxidants, the antioxidant activity of coffee extracts was also evaluated. The correlation analysis and principal component analysis indicated that the combination of HPLC fingerprint and quantitative analysis can be readily utilized as a quality assessment tool for coffee and other plant products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Coffea/química , Análise de Alimentos/métodos , Alcaloides/análise , Antioxidantes/química , Cafeína/análise , Cromatografia Líquida de Alta Pressão/estatística & dados numéricos , Análise de Alimentos/estatística & dados numéricos , Qualidade dos Alimentos , Fenóis/análise , Análise de Componente Principal , Reprodutibilidade dos Testes , Sementes/química , Teobromina/análise
18.
Artigo em Inglês | MEDLINE | ID: mdl-31830662

RESUMO

Olanzapine is one of the most commonly used drugs for the treatment of schizophrenia and depression of various origins. Its levels are usually measured in the blood, but the collection of this diagnostic material poses many problems. Therefore, we aimed to develop a fast and sensitive method to determine olanzapine levels in saliva, an easily available diagnostic material. To reduce the consumption of toxic solvents during analyte extraction from saliva, olanzapine was isolated by solid-phase extraction using Oasis® MCX cartridges. Chromatographic analysis was performed by LC-MS/MS, with C18 resin in Atlantis® T3 column as the stationary phase and 2 mM ammonium formate and acetonitrile as the mobile phase (flow rate of 0.25 mL/min, with elution gradient). The specificity, linearity, sensitivity, precision, accuracy, and stability of the optimized method were validated. The relative standard deviation for intra-day precision for three tested olanzapine concentrations did not exceed 12.7%; the highest accuracy value was 113.9%. The recoveries from spiked saliva samples were greater than 87.3% for the two olanzapine concentrations studied. The developed method was then used to determine olanzapine levels in human saliva obtained from 15 patients treated with different doses of olanzapine.


Assuntos
Cromatografia Líquida/métodos , Olanzapina/análise , Saliva/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Adulto , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
19.
Molecules ; 24(16)2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31416290

RESUMO

Neuroleptics and antiepileptics are excreted in saliva, which can, therefore, be very useful in determining their concentration in the body. This study presents a method developed to simultaneously identify five neuroleptics-olanzapine, quetiapine, risperidone, aripiprazole, and clozapine-and the antiepileptic carbamazepine together with their metabolites: N-demethyl olanzapine, norquetiapine, 9-OH-risperidone, dehydroaripiprazole, N-desmethylclozapine, and carbamazepine-10,11 epoxide. Chlordiazepoxide was used as the internal standard. Strata-X-C columns were used for isolation of the compounds. Chromatographic analysis was carried out using UHPLC with a diode array detector (DAD). A mixture of acetonitrile and water with the addition of formic acid and 0.1% triethylamine was used as the mobile phase. The developed method was validated by determining the linearity for all analytes in the range 10-1000 ng/mL and the value of R2 > 0.99. Intra- and inter-day precision were also determined, and the relative standard deviation (RSD) value in both cases did not exceed 15%. To determine the usefulness of the developed method, saliva samples were collected from 40 people of both sexes treated with the tested active substances both in monotherapy and in polypragmasy. In all cases, the active substances tested were identified.


Assuntos
Anticonvulsivantes/farmacologia , Antipsicóticos/farmacocinética , Cromatografia Líquida de Alta Pressão , Saliva/metabolismo , Anticonvulsivantes/química , Antipsicóticos/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/normas , Estabilidade de Medicamentos , Humanos , Estrutura Molecular , Reprodutibilidade dos Testes
20.
Molecules ; 24(17)2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31450672

RESUMO

Morus alba L. (white mulberry) has been commonly used as a functional food and for medicinal purposes. Hence, the aim of the study was to compare the phenolic profile of white mulberry commercial samples in relation to their antioxidant potential and acetylcholinesterase (AChE) inhibitory activity. It is of interest to determine whether herbal products originating from different commercial sources differ in their phenolic profiles. For this purpose, a simple and rapid high-performance liquid chromatography (HPLC) method was used for the separation and determination of ten major phenolic compounds. Total phenolic (TPC), total flavonoid (TFC), and total phenolic acid contents (TPAC), as well as l(+)-ascorbic acid (ASA) contents, were determined. The antioxidant potential was assessed by DPPH (2,2-diphenyl-1-picrylhydrazyl radical) scavenging activity and ferric-reducing/antioxidant power (FRAP) assay, while the AChE inhibitory activity was determined by the Ellman assay for water extracts. The study revealed that excluding two herbal products containing fruits and a sample containing leaves of white mulberry, yerba mate and lemon, the remaining samples were generally consistent in terms of phenolic composition as well as antioxidant potential and AChE inhibitory activity. This reflects the health-promoting properties of the samples under study. Moreover, the results showed that the water extracts of white mulberry were richer in phenolic compounds and presented higher antioxidant activity than the hydromethanolic extracts. However, the water extracts showed low inhibitory activity against AChE. Moreover, the correlation analysis indicated a high positive relationship between phenolic composition and antioxidant activity in extracts of white mulberry. Overall, the obtained results may be useful in the evaluation of new dietary supplements and food products. The water extracts of white mulberry could be used for antioxidant purposes, while the hydromethanolic extracts could be incorporated in antioxidant formulations.


Assuntos
Morus/química , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Ácido Ascórbico/química , Cromatografia Líquida de Alta Pressão , Flavonoides , Hidroxibenzoatos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia
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