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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.
Fetal Diagn Ther ; 34(2): 96-102, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23796591

RESUMO

INTRODUCTION: A standardized three-dimensional ultrasonographic (3DUS) protocol is described that allows fetal face reconstruction. Ability to identify cleft lip with 3DUS using this protocol was assessed by operators with minimal 3DUS experience. MATERIAL AND METHODS: 260 stored volumes of fetal face were analyzed using a standardized protocol by operators with different levels of competence in 3DUS. The outcomes studied were: (1) the performance of post-processing 3D face volumes for the detection of facial clefts; (2) the ability of a resident with minimal 3DUS experience to reconstruct the acquired facial volumes, and (3) the time needed to reconstruct each plane to allow proper diagnosis of a cleft. RESULTS: The three orthogonal planes of the fetal face (axial, sagittal and coronal) were adequately reconstructed with similar performance when acquired by a maternal-fetal medicine specialist or by residents with minimal experience (72 vs. 76%, p = 0.629). The learning curve for manipulation of 3DUS volumes of the fetal face corresponds to 30 cases and is independent of the operator's level of experience. DISCUSSION: The learning curve for the standardized protocol we describe is short, even for inexperienced sonographers. This technique might decrease the length of anatomy ultrasounds and improve the ability to visualize fetal face anomalies.


Assuntos
Face/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Face/anormalidades , Imageamento Tridimensional/métodos , Imageamento Tridimensional/estatística & dados numéricos , Anormalidades Maxilofaciais/diagnóstico por imagem , Variações Dependentes do Observador , Padrões de Referência , Ultrassonografia Pré-Natal/estatística & dados numéricos
3.
Talanta ; 134: 183-193, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25618656

RESUMO

There is a growing interest in the pharmaceutical field concerning isoflavones topical delivery systems, especially with regard to their skin care properties and antiherpetic activity. In this context, the present work describes an ultra-fast liquid chromatography method (UFLC) for determining daidzein, glycitein, and genistein in different matrices during the development of topical systems containing isoflavone aglycones (IA) obtained from soybeans. The method showed to be specific, precise, accurate, and linear (0.1 to 5 µg mL(-1)) for IA determination in soybean acid extract, IA-rich fraction obtained after the purification process, IA loaded-nanoemulsions, and topical hydrogel, as well as for permeation/retention assays in porcine skin and porcine esophageal mucosa. The matrix effect was determined for all complex matrices, demonstrating low effect during the analysis. The stability indicating UFLC method was verified by submitting IA to acidic, alkaline, oxidative, and thermal stress conditions, and no interference of degradation products was detected during analysis. Mass spectrometry was performed to show the main compounds produced after acid hydrolysis of soybeans, as well as suggest the main degradation products formed after stress conditions. Besides the IA, hydroxymethylfurfural and ethoxymethylfurfural were produced and identified after acid hydrolysis of the soybean extract and well separated by the UFLC method. The method's robustness was confirmed using the Plackett-Burman experimental design. Therefore, the new method affords fast IA analysis during routine processes, extract purification, products development, and bioanalytical assays.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Genisteína/isolamento & purificação , Glycine max/química , Isoflavonas/isolamento & purificação , Administração Tópica , Animais , Transporte Biológico , Esôfago/efeitos dos fármacos , Esôfago/metabolismo , Furaldeído/análogos & derivados , Furaldeído/química , Furaldeído/isolamento & purificação , Furaldeído/farmacologia , Genisteína/química , Genisteína/farmacologia , Hidrogéis , Hidrólise , Isoflavonas/química , Isoflavonas/farmacologia , Mucosa/efeitos dos fármacos , Mucosa/metabolismo , Permeabilidade , Extratos Vegetais/química , Pele/efeitos dos fármacos , Pele/metabolismo , Suínos
4.
Carbohydr Polym ; 98(1): 726-35, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23987405

RESUMO

In the present study we evaluated the complexation of daidzein/genistein/glycitein, present in an isoflavone enriched fraction (IEF), with ß-cyclodextrin and 2-hydroxypropyl-ß-cyclodextrin (HPßCD). Based on the increased solubility and higher complexation efficiency, IEF and HPßCD solid complexes were prepared by kneading, freeze-drying, co-evaporation, spray-drying and microwave. The solid complexes were characterized using Fourier transformed-infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, and nuclear magnetic resonance spectroscopy, and the isoflavone content and solubility were determined by liquid chromatography. The results suggest that the isoflavones daidzein, genistein and glycitein may be externally associated to HPßCD as well as that isoflavones/HPßCD inclusion complexes are formed through the insertion of B-ring into the cyclodextrin cavity. Except for the freeze-dried IEF/HPßCD solid complex, all complexes showed similar content and solubility. In conclusion, the three isoflavones showed to be able to simultaneously complex with HPßCD.


Assuntos
Ciclodextrinas/química , Glycine max/química , Isoflavonas/química , Solubilidade
5.
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
6.
Rev. bras. farmacogn ; 26(2): 259-267, Jan.-Apr. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-779018

RESUMO

ABSTRACT The present work was designed to obtain a fraction containing high concentration of isoflavone-aglycones from Glycine max (L.) Merr., Fabaceae, named isoflavone enriched-fraction, from a dry extract containing isoflavones-glycosides. A simple and low cost method was proposed: extraction of isoflavone glycosides from the G. max dry extract with a proper solvent, hydrolysis of the glycosides, recovery of the aglycones, and purification of the fraction containing high isoflavone-aglycones concentration. All the extraction and purification parameters were optimized based on the isoflavones yields, which were analyzed by liquid chromatography and expressed as total isoflavone aglycones. The optimization of the process conditions was accomplished using the classical one-variable-at-a-time method. The identity and purity of the isoflavones contained in this enriched fraction were determined by LC/UV/ESI/MS analysis, Fourier transformed-infrared spectroscopy, and 1H and 13C nuclear magnetic resonance spectroscopy. The physicochemical properties of the isoflavone enriched-fraction were evaluated by scanning electron microscopy, X-ray diffraction and differential scanning calorimetry. The moisture content, particle size, equilibrium solubility and thermal and photostability were also determined. The high isoflavone-aglycone content (daidzein, 489.35 mg/g; glycitein, 251.02 mg/g and genistein, 158.96 mg/g) as well as the high purity obtained (90% of total isoflavones) make this fraction a promising novel raw material for the production of isoflavone-aglycones based pharmaceuticals or functional foods.

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