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1.
Foods ; 11(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35159521

RESUMO

BACKGROUND: elemental deficiency may result in the malfunctioning of human organisms. Sprouts, with their attractive looks and well-established popularity, may be considered as alternative sources of elements in the diet. Moreover, the uptake of micro- and macronutrients from sprouts is better when compared to other vegetable sources. The aim of the study was to determine and compare the level of the selected essential minerals and trace elements in 25 sprouts from different botanical families, to preselect the richest species of high importance for human diets. METHODS: the Cu, Zn, Mn, Fe, Mg, Ca determinations were performed using atomic absorption spectrometry with flame atomization and iodine by the colorimetric method. RESULTS: beetroot sprouts had the highest levels of Zn, Fe, and Mg, while onion sprouts were the richest in Mn and Ca, among all of the tested sprouts. Sprouts of the Brassicaceae family were generally richer in Ca, Mg, and Zn than sprouts from the Fabaceae family. Results allow preselection of the most perspective sprouts as possible dietary sources of essential minerals and trace elements. For rucola, leeks, onions, and beetroot sprouts, the data on minerals and trace element compositions were performed for the first time.

2.
Talanta ; 237: 122937, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736668

RESUMO

New highly sensitive voltammetric method for captopril (CPT) determination was developed. The main novelty of the work was the application of a renewable amalgam film electrode (Hg(Ag)FE) for this purpose. During the research instrumental parameters of the developed method were optimized and were as follows: tw = ts = 5 ms, Es = 5 mV, ΔE = 100 mV. Preconcentration potential and time were equal to 100 mV and 20 s, respectively. All measurements were conducted in electrolyte consisted of 0.1 M HClO4. Limit of detection was calculated and was equal to 1.9 nM (0.39 ng mL-1) for 20 s preconcentration time and Hg(Ag)FE surface area approximately 11.2 mm2. Linearity was achieved in the concentration range 0.05-1 µM. Repeatability of the method expressed as variation coefficient was estimated at 3.5% (0.15 µM CPT, n = 10). Applicability of the method was confirmed by analysis of tablets containing CPT and urine. Recoveries were in the range from 95 to 109% suggesting that the method might be assumed as accurate. Obtained results were also in good agreement with the producer declaration.


Assuntos
Captopril , Mercúrio , Eletrodos
3.
Sensors (Basel) ; 21(17)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34502683

RESUMO

In this work, a new sensitive voltammetric method for the determination of rifampicin without time-consuming preconcentration is presented. The objective was to develop a simple, fast and sensitive voltammetric procedure for the analysis of rifampicin in pharmaceutical products. The cyclic renewable mercury film silver-based electrode (Hg(Ag)FE) was applied as a working electrode for this purpose. The optimal conditions for the determination of rifampicin were defined, in terms of the composition of supporting electrolyte (including pH) and instrumental parameters (potential and time of deposition, step potential, pulse height). The method was validated resulting in a satisfactory linearity range of 0.4-250.0 µgmL-1; the limits of detection and quantification are 0.12 µgmL-1 and 0.4 µgmL-1, respectively; and the repeatability of the method expressed as RSD is 4.1% (n = 6) with a surface area of 10.9 mm2. The proposed method was successfully applied in the analysis of rifampicin in simple and composed pharmaceutical formulations.


Assuntos
Mercúrio , Preparações Farmacêuticas , Eletroquímica , Eletrodos , Rifampina
4.
Molecules ; 25(22)2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187198

RESUMO

The oxidation of lomefloxacin (LOM) and balofloxacin (BAL) under the influence of azo initiator of radical reactions of 4,4'-azobis(4-cyanopentanoic acid) (ACVA) and H2O2 was examined. Oxidation using H2O2 was performed at room temperature while using ACVA at temperatures: 40, 50, 60 °C. Additionally, the oxidation process of BAL under the influence of KMnO4 in an acidic medium was investigated. New stability-indicating HPLC methods were developed in order to evaluate the oxidation process. Chromatographic analysis was carried out using the Kinetex 5u XB-C18 100A column, Phenomenex (Torrance, CA, USA) (250 × 4.6 mm, 5 µm particle size, core shell type). The chromatographic separation was achieved while using isocratic elution and a mobile phase with the composition of 0.05 M phosphate buffer (pH = 3.20 adjusted with o-phosphoric acid) and acetonitrile (87:13 v/v for LOM; 80:20 v/v for BAL). The column was maintained at 30 °C. The methods were validated according to the ICH guidelines, and it was found that they met the acceptance criteria. An oxidation process followed kinetics of the second order reaction. The most probable structures of LOM and BAL degradation products formed were assigned by the UHPLC/MS/MS method.


Assuntos
Compostos Azo/química , Cromatografia Líquida de Alta Pressão/métodos , Fluoroquinolonas/química , Peróxido de Hidrogênio/química , Permanganato de Potássio/química , Espectrometria de Massas em Tandem/métodos , Valeratos/química , Estabilidade de Medicamentos , Hidrólise , Cinética , Limite de Detecção , Modelos Lineares , Oxirredução , Oxigênio/química , Reprodutibilidade dos Testes , Temperatura
5.
Pharm Biol ; 55(1): 114-123, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27925492

RESUMO

CONTEXT: Crataegus monogyna L. (Rosaceae) (CM), Equisetum telmateia L. (Equisataceae) (ET), Geranium purpureum Vil. (Geraniaceae) (GP), Mentha suaveolens Ehrh. (Lamiaceae) (MS), and Lavandula stoechas L. spp. luisieri (Lamiaceae) (LS) are all medicinal. OBJECTIVE: To evaluate the antioxidant, antiproliferative and antimicrobial activities of plant extracts and quantify individual phenolics and zinc. MATERIAL AND METHODS: Aerial part extracts were prepared with water (W), ethanol (E) and an 80% mixture (80EW). Antioxidant activity was measured with TAA, FRAP and RP methods. Phenolics were quantified with a HPLC. Zinc was quantified using voltammetry. Antibacterial activity (after 48 h) was tested using Enterococcus faecalis, Bacillus cereus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Listeria monocytogenes. Antiproliferative activity (after 24 h) was tested using HEP G2 cells and fibroblasts. RESULTS: Solvents influenced results; the best were E and 80EW. GP had the highest antioxidant activity (TAA and FRAP of 536.90 mg AAE/g dw and 783.48 mg TE/g dw, respectively). CM had the highest zinc concentration (37.21 mg/kg) and phenolic variety, with neochlorogenic acid as the most abundant (92.91 mg/100 g dw). LS was rich in rosmarinic acid (301.71 mg/100 g dw). GP and LS inhibited the most microorganisms: B. cereus, E. coli and S. aureus. GP also inhibited E. faecalis. CM had the lowest MIC: 5830 µg/mL. The antibacterial activity is explained by the phenolics present. LS and CM showed the most significant anti-proliferative activity, which is explained by their zinc content. CONCLUSION: The most promising plants for further studies are CM, LS and GP.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Equisetum/química , Neoplasias Hepáticas/tratamento farmacológico , Extratos Vegetais/farmacologia , Zinco/análise , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Bactérias/crescimento & desenvolvimento , Cloretos/química , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Relação Dose-Resposta a Droga , Compostos Férricos/química , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Testes de Sensibilidade Microbiana , Oxirredução , Fenóis/análise , Fitoterapia , Componentes Aéreos da Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Portugal , Solventes/química
6.
Acta Pol Pharm ; 73(3): 749-54, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27476293

RESUMO

Caries is the most popular problem affecting teeth and this is the reason why so many temporary dental filling materials are being developed. An example of such filling is zinc oxide paste mixed with eugenol, Thymodentin and Coltosol F®. Zinc-oxide eugenol is used in dentistry because of its multiplied values: it improves heeling of the pulp by dentine bridge formation; has antiseptic properties; is hygroscopic. Because of these advantages compouds of zinc oxide are used as temporary fillings, especially in deep caries lesions when treatment is oriented on support of vital pulp. Temporary dental fillings based on zinc oxide are prepared ex tempone by simple mixing powder (Thymodentin) and eugenol liqiud together or a ready to use paste Coltosol F®. Quantitative composition depends mainly on experience of person who is preparing it, therefore, exact qualitative composition of dental fillings is not replicable. The main goal of the study was to develop appropriate dental fillings in solid form containing set amount of zinc oxide. Within the study, the influence of preparation method on solid dental fillings properties like mechanical properties and zinc ions release were examined.


Assuntos
Materiais Dentários/química , Cimento de Óxido de Zinco e Eugenol/química , Restauração Dentária Temporária , Fenômenos Mecânicos , Zinco/análise
7.
Biol Trace Elem Res ; 160(1): 123-31, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24913100

RESUMO

It has been demonstrated that zinc exerts its beneficial influence on skin fibroblasts. Propolis, a complex mixture of plant-derived and bees' products, was reported to stimulate cicatrization processes in skin and prevent infections. The aim of this study was to find out how zinc and propolis influence human skin fibroblasts in cell culture and to compare the effect of individual compounds to the effect of a mixture of zinc and propolis. In this study, zinc, as zinc aspartate, at a concentration of 16 µM, increased human fibroblasts proliferation in cell culture, whereas propolis at a concentration of 0.01% (w/v) revealed antiproliferative and cytotoxic action followed by mild cell necrosis. In culture, zinc was effectively transported into fibroblasts, and propolis inhibited the amount of zinc incorporated into the cells. An addition of propolis to the medium caused a decrease in the Zn(II) amount incorporated into fibroblasts. The obtained results also indicate an appreciable antioxidant property of propolis and revealed its potential as a supplement when applied at doses lower than 0.01% (w/v). In conclusion, the present study showed that zinc had a protective effect on human cultured fibroblasts' viability, although propolis revealed its antiproliferative action and caused mild necrosis.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Polifenóis/química , Polifenóis/farmacologia , Própole/química , Própole/farmacologia , Pele/citologia , Zinco/farmacologia , Antioxidantes/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Própole/metabolismo , Proteínas/análise , Pele/efeitos dos fármacos , Pele/metabolismo , Espectrofotometria Atômica , Zinco/metabolismo
8.
Int J Pharm ; 455(1-2): 104-12, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23916826

RESUMO

Examination of the stability of clonazepam, diazepam, alprazolam, haloperidol, and doxepin in basic solutions was performed, together with an assessment of the kinetic (k, t0.1i t0.5) and thermodynamic (Ea, ΔH(++)i ΔS(++)) stability-indicating parameters, which were compared with the lipophilicity (logP) of the studied drugs. It was observed that the calculated values of Ea, ΔH(++) and ΔS(++) for the studied drugs increased from 41.04 kJ/mol to 125.50 kJ/mol, from 37.82 kJ/mol to 122.24 kJ/mol and from -167.09 J/Kmol to 53.02 J/Kmol, respectively, along with an increase of lipophilicity (logP) from 2.12 to 4.30 for the most hydrophilic alprazolam to the most lipophilic haloperidol. The degradation products were identified using UPLC/MS/MS method.


Assuntos
Alprazolam/química , Clonazepam/química , Diazepam/química , Doxepina/química , Haloperidol/química , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Termodinâmica
9.
Acta Pol Pharm ; 70(6): 961-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24383319

RESUMO

Zinc is an interesting target for detection as it is one of the elements necessary for the proper functioning of the human body, its excess and deficiency can cause several symptoms. Several techniques including electrochemistry have been developed but require laboratory equipment, preparative steps and mercury or complex working electrodes. We here described the development of a robust, simple and commercially available electrochemical system. Differential pulse (DP) voltammetry was used for this purpose with the cyclic renewable mercury film silver based electrode (Hg(Ag)FE) and 0.05 M KNO3 solution as a supporting electrolyte. The effect of various factors such as: preconcentration potential and time, pulse amplitude and width, step potential and supporting electrolyte composition are optimized. The limits of detection (LOD) and quantification (LOQ) were 1.62 ng/mL and 4.85 ng/mL, respectively. The repeatability of the method at a concentration level of the analyte as low as 3 ng/mL, expressed as RSD is 3.5% (n = 6). Recovery was determined using certified reference material: Virginia Tobacco Leaves (CTA-VTL-2). The recovery of zinc ranged from 96.6 to 106.5%. The proposed method was successfully applied for determination of zinc in bee products (honey, propolis and diet supplements) after digestion procedure.


Assuntos
Abelhas , Suplementos Nutricionais/análise , Eletroquímica/instrumentação , Mel/análise , Mercúrio/química , Própole/análise , Prata/química , Zinco/análise , Animais , Calibragem , Eletroquímica/normas , Eletrodos , Limite de Detecção , Padrões de Referência , Reprodutibilidade dos Testes
10.
Amino Acids ; 40(1): 249-58, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20532950

RESUMO

Zinc exhibits antidepressant-like activity in preclinical tests/models. Moreover, zinc homeostasis is implicated in the pathophysiology of affective disorders. The aim of the present study was to examine the effect of chronic zinc, citalopram and imipramine intraperitoneal administration on the presynaptic and extracellular zinc concentration in the rat prefrontal cortex and hippocampus. We used two methods: zinc-selenium histochemistry (which images the pool of presynaptic-vesicle zinc) and anodic stripping voltammetry (ASV) for zinc determination in microdialysate (which assays the extracellular zinc concentration). We report that chronic (14 ×) zinc (hydroaspartate, 10 and 65 mg/kg) and citalopram (20 mg/kg) administration increased the pool of presynaptic zinc (by 34, 50 and 37%, respectively) in the rat prefrontal cortex. The 21% increase induced by imipramine (20 mg/kg) was marginally significant. Likewise, zinc (hydroaspartate, 65 mg/kg), citalopram and imipramine increased the extracellular zinc (although with a different pattern: time point, area under the curve and/or basal level) in this brain region. Furthermore, zinc induced an increase in presynaptic (by 65%) and extracellular zinc (by 90%) in the hippocampus, while both citalopram and imipramine did not. These results indicate that all of the treatments increase presynaptic/extracellular zinc concentrations in the rat prefrontal cortex, which may then contribute to their antidepressant mechanisms. Alterations induced by zinc (but not antidepressants) administration in the hippocampus may be related to specific zinc mechanisms. All the data (previous and present) on the effect of antidepressant treatments on the presynaptic/extracellular zinc concentrations suggest the involvement of this biometal presynaptic/synaptic homeostasis in the antidepressant mechanism(s).


Assuntos
Antidepressivos/administração & dosagem , Antidepressivos/metabolismo , Espaço Extracelular/metabolismo , Hipocampo/metabolismo , Córtex Pré-Frontal/metabolismo , Zinco/administração & dosagem , Zinco/metabolismo , Animais , Citalopram/administração & dosagem , Espaço Extracelular/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Humanos , Imipramina/administração & dosagem , Injeções Intraperitoneais , Masculino , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Wistar
11.
Pharmacol Rep ; 62(6): 1211-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21273680

RESUMO

Preclinical and clinical data indicate the involvement of zinc in the pathophysiology and therapy of depression. A relationship between zinc-deficiency and depression symptoms was recently proposed. The present study investigated alterations in spontaneous locomotor activity and zinc concentrations in the serum, hippocampus and frontal cortex; these alterations were induced by subjecting rats to a zinc-deficient diet, prior subjected after birth to zinc-supplemented diet. Body weight was significantly reduced in animals subjected to the four-week zinc-deficient diet compared to those subjected to the zinc-adequate diet. The two-week zinc-deficient diet induced a significant increase in locomotor activity in all measured time periods (5, 30 and 60 min by 44-62%). The four-week zinc-deficient diet did not affect locomotor activity, while the six-week zinc-deficient diet resulted in a 45% increase in the 5 min time period. Serum zinc concentrations were significantly reduced (by 29%) in animals subjected to the four-week zinc-deficient diet but not in those subjected to the two- or six-week zinc-deficient diets. The zinc-deficient diet did not influence the zinc concentration in the examined brain regions regardless of the length. These results indicate that post-birth supplementation with zinc may protect zinc-deficient diet-induced rapid alterations in zinc homeostasis.


Assuntos
Suplementos Nutricionais , Hipocampo/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Compostos de Zinco/administração & dosagem , Zinco/administração & dosagem , Zinco/deficiência , Animais , Peso Corporal , Dieta , Masculino , Minerais/administração & dosagem , Minerais/sangue , Minerais/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo , Zinco/sangue , Zinco/metabolismo
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