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1.
AAPS PharmSciTech ; 17(2): 358-67, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26162976

RESUMO

Several studies have shown the potential use of Ilex paraguariensis in developing products with the aim to protect biological systems against oxidative stress-mediated damages. In the same way, technological studies have demonstrated the feasibility of obtaining dry products, by spray-drying process, from aqueous extracts of I. paraguariensis in laboratory. The present work was designed to develop pellets by extrusion/spheronization process, from an I. paraguariensis spray-dried powder. The pellets were characterized with respect to their chemical, physical, and technological properties, and the thermal and the photostability of the main polyphenol constituents were investigated. The pellets exhibited adequate size, shape, and high process yield (78.7%), as well as a good recovery of the total polyphenols (>95%) and a good dissolution in water (89.44 to 100.05%). The polyphenols were stable against light when conditioned in amber glass bottles; unstable against heat when the samples were conditioned either in open glass bottles or in hermetically sealed glass bottles and demonstrated to be hygroscopic and sensible to the temperature, especially when stored in permeable flasks. These findings pointed to the relevance of reducing the residual moisture content of pellets as well as of conditioning them in opaque humidity tight packages under low temperatures. The feasibility of obtaining pellets from an I. paraguariensis spray-dried powder using extrusion/spheronization technique was, for the first time, demonstrated. This finding represents a novelty for the herbal products in both pharmaceutical and food fields.


Assuntos
Implantes de Medicamento/química , Ilex paraguariensis/química , Extratos Vegetais/química , Química Farmacêutica/métodos , Estabilidade de Medicamentos , Umidade , Tamanho da Partícula , Ácidos Polimetacrílicos/química , Polifenóis/química , Pós/química , Solubilidade , Tecnologia Farmacêutica/métodos , Temperatura
2.
Basic Clin Pharmacol Toxicol ; 112(6): 385-91, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23331460

RESUMO

Non-alcoholic steatohepatitis (NASH) is a frequent condition in obese patients that may progress to end-stage liver disease. This study was designed to evaluate the modulation of this condition by use of quercetin (Q), a flavonoid largely found in vegetable foods, with known anti-inflammatory and antioxidant properties, in the experimental model of non-alcoholic steatohepatitis (NASH) using a diet deficient in methionine and choline (MCD). Male C57BL6 mice were divided into four groups (n = 16): (i) Control plus vehicle (control ration plus carboxymethylcellulose 1% used as vehicle, CO + V); (ii) Control ration plus Q 50 mg/kg (CO + Q); (iii) MCD diet plus vehicle (NASH + V); and (iv) MCD diet plus Q (NASH + Q). Diets were administered for 4 weeks. At the end of the experimental period, liver alterations, bioindicators of oxidative stress and DNA damage were assessed. NASH was diagnosed in 100% of the mice that were fed the MCD diet. In addition, a significant increase in DNA damage in liver tissue from NASH + V group was observed in comparison with CO + V. The group NASH + Q showed a significant decrease in hepatic damage enzymes, lipoperoxidation, DNA damage and a lower degree of macrovesicular steatosis, ballooning and inflammatory process. These findings suggest that Q may have protective effects by improving liver integrity in NASH.


Assuntos
Antioxidantes/uso terapêutico , Dano ao DNA , Fígado Gorduroso/prevenção & controle , Quercetina/uso terapêutico , Animais , Antioxidantes/administração & dosagem , Deficiência de Colina , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Dieta , Modelos Animais de Doenças , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Função Hepática , Masculino , Metionina/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Quercetina/administração & dosagem
3.
J Chromatogr Sci ; 50(2): 114-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22298760

RESUMO

Recent studies have shown the effect of soy isoflavones in preventing skin photoaging and photocarcinogenesis, especially for genistein (GEN). Nanoemulsions have been proposed as a delivery system for GEN administration due to the low water solubility of this isoflavone. This article describes the validation of an isocratic liquid chromatography method to determine GEN in porcine ear skin layers from nanoemulsions before and after incorporation into hydrogels. The analyses are performed on a reversed-phase C18 column using a mobile phase composed of methanol-water (70:30, v/v) under acid conditions (at pH 3.0) and UV detection at 270 nm. The method is linear in the range of 0.1-10 µg/mL (r(2) > 0.999) in the presence of skin extracts. The low limit of quantitation is estimated as 0.1 µg/mL. No interferences from formulation excipients or skin layer compounds are detected. The RSD values for intra- and inter-day precision are lower than 15%. Recovery ranged from approximately 90% to 110%. The method is applied to estimate GEN retention in the skin from formulations using Franz diffusion cells. The highest amount of GEN is detected in the epidermis (185 µg/cm(2)). In conclusion, the method proved to be specific, precise, and accurate in determining GEN amounts from formulations in skin retention studies.


Assuntos
Cromatografia Líquida/métodos , Emulsões , Genisteína/metabolismo , Hidrogéis , Pele/metabolismo , Animais , Nanoestruturas , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Suínos
4.
J Med Food ; 14(4): 413-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21370969

RESUMO

The present work was designed to produce an Ilex paraguariensis spray-dried powder (SDP), in semi-industrial scale, in order to characterize its technological and chemical properties as well as to evaluate the thermal stability and photostability of the main polyphenol constituents. The yield of the spray-drying process was satisfactory (67%). The resulting SDP showed to be a material presenting spherical particles with a mean size of 19.6 µm, smooth surface, and good flow properties. The four polyphenol compounds previously reported for the species--neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, and rutin--were identified. Regarding the photostability test, the polyphenols present in the SDP proved to be stable against ultraviolet C radiation for 48 hours, independently of the packaging material. In the thermal stability test, the polyphenols were demonstrated to be hygroscopic and responsive to temperature (40°C) under an atmosphere of high relative humidity (75%) for 4 months, especially when the SDP was conditioned in permeable flasks. These findings demonstrate that heat and residual moisture content play an important role in the stability of the polyphenols and reinforce the relevance of conditioning SDP in humid tight packages under low temperatures.


Assuntos
Flavonoides/análise , Ilex paraguariensis/química , Fenóis/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Ácido Clorogênico/análise , Cromatografia Líquida , Dessecação , Temperatura Alta , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Polifenóis , Pós , Rutina/análise
5.
Drug Dev Ind Pharm ; 37(8): 886-93, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21247375

RESUMO

OBJECTIVE: To evaluate the effect of different cyclodextrins (ß-cyclodextrin [ß-CD], methyl-ß-cyclodextrin [Mß-CD], or hydroxypropyl-ß-cyclodextrin [HPß-CD]) and/or hydrophilic polymers (carboxymethylcellulose, hydroxypropylmethylcellulose [HPMC], polyethyleneglycol, or polyvinylpyrrolidone [PVP]) on daidzein solubility in water. MATERIALS AND METHODS: The corresponding associations were characterized in aqueous media using phase-solubility studies. The morphology of daidzein/cyclodextrin freeze-dried complexes was characterized using scanning electron microscopy, and their spatial configuration was proposed by means of nuclear magnetic resonance spectroscopy. RESULTS AND DISCUSSION: In the presence of 6 mM of cyclodextrins, the solubility of daidzein in water was significantly enhanced: 5.7-fold (ß-CD), 7.2-fold (Mß-CD), and 9.4-fold (HPß-CD). The analysis of the three solid complexes proved that the formation of inclusion complexes occurred through the insertion of the B and C rings of daidzein molecule into the cyclodextrins cavity. The association of daidzein/cyclodextrin complexes to the hydrophilic polymers HPMC or PVP (1%, w/w) was able to improve the solubility of daidzein even further. CONCLUSION: The highest solubilizing effect was obtained for daidzein/HPß-CD/PVP ternary system (12.7-fold).


Assuntos
Ciclodextrinas/química , Isoflavonas/química , Fitoestrógenos/química , Polímeros/química , Química Farmacêutica , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética/métodos , Solubilidade , Água/química
6.
AAPS PharmSciTech ; 10(1): 235-42, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19280349

RESUMO

The present study was designed to investigate the influence of operating conditions (temperature, stirring time, and excess amount of quercetin) on the complexation of quercetin with beta-cyclodextrin using a 2(3) factorial design. The highest aqueous solubility of quercetin was reached under the conditions 37 degrees C/24 h/6 mM of quercetin. The stoichiometric ratio (1:1) and the apparent stability constant (Ks = 230 M(-1)) of the quercetin/beta-cyclodextrin complex were determined using phase-solubility diagrams. The semi-industrial production of a 1:1 quercetin/beta-cyclodextrin solid complex was carried out in aqueous solution followed by spray-drying. Although the yield of the spray-drying process was adequate (77%), the solid complex presented low concentration of quercetin (0.14%, w/w) and, thus, low complexation efficiency. The enhancement of aqueous solubility of quercetin using this method was limited to 4.6-fold in the presence of 15 mM of beta-cyclodextrin. Subsequently, an inclusion complex was prepared via physical mixture of quercetin with beta-cyclodextrin (molar ratio of 1:1 and quercetin concentration of 23% (w/w)) and characterized using infrared spectroscopy, differential scanning calorimetry, nuclear magnetic resonance spectroscopy, and scanning electron microscopy analyses. The enhancement of aqueous solubility of quercetin using this method was 2.2-fold, similar to that found in the complex prepared in aqueous solution before the spray-drying process (2.5-fold at a molar ratio of 1:1, i.e., 6 mM of quercetin and 6 mM of beta-cyclodextrin).


Assuntos
Quercetina/química , Tecnologia Farmacêutica/métodos , beta-Ciclodextrinas/química , Varredura Diferencial de Calorimetria , Dessecação , Estabilidade de Medicamentos , Cinética , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Modelos Químicos , Solubilidade , Espectrofotometria Infravermelho , Propriedades de Superfície , Temperatura
7.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; 42(4): 531-537, out.-dez. 2006. tab, graf
Artigo em Português | LILACS | ID: lil-446374

RESUMO

Os objetivos deste estudo foram desenvolver e avaliar a estabilidade física de loções do tipo O/A contendo 6 por cento (p/p) do filtro solar octilmetoxicinamato (OMC) ou metilbenzilidenocânfora (MBC). As formulações foram armazenadas em temperatura ambiente durante seis meses e durante este período foram avaliadas com relação às suas características macroscópicas, viscosidade, comportamento reológico, índice de óleo, espalhabilidade e Fator de Proteção Solar (FPS). Os resultados demonstram que as formulações foram estáveis por seis meses. Os valores de FPS foram significativamente (P < 0,05) maiores para a formulação MBC. Em contrapartida, a formulação OMC apresentou valores de espalhabilidade significativamente (P < 0,05) superiores e valores de viscosidade significativamente (P < 0,05) inferiores durante todo o período de armazenamento.


The objectives of this study were to develop and to evaluate the physical stability of O/W lotions containing 6 percent (w/w) of the sunscreen octylmethoxycinnamate (OMC) or methyl benzylidene camphor (MBC). The formulations were stored at room temperature, for six months and during this period its macroscopic characteristics, viscosity and rheological behavior, oil indexes, spreading properties and Sun Protection Factor (SPF) were evaluated. The results demonstrate that both formulations were stable for six months. The SPF values were significantly (P < 0.05) higher for MBC formulation. On the other hand, the OMC formulation presented significantly (P < 0.05) higher spreading and lower viscosity values during the storage period.


Assuntos
Loções de Beleza , Estabilidade de Cosméticos , Protetores Solares , Química Farmacêutica , Cosméticos
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