RESUMEN

Oleogels have been explored as fat substitutes due to their healthier composition compared to trans and saturated fats, also presenting interesting technological perspectives. The aim of this study was to investigate the compositional perspective of multicomponent oleogels. Structuring ability of lecithin (LEC) (20 or 90 wt% of phosphatidylcholine - PC) combined with glycerol monostearate (GMS), sorbitan monostearate (SMS) or sucrose monostearate (SAC) in sunflower oil was evaluated from oleogels properties. The thermal and rheological properties, microstructure and stability of the oleogels were affected by the difference in the chemical composition of LEC and the ratio between LEC and different surfactants. Interestingly, low-phosphatidylcholine LEC (L20) performed better, although systems formed with reduced amounts of LEC tended to be softer (LEC-GMS) and present high oil holding capacity (LEC-SMS). The mixtures of LEC and monostearate-based surfactants showed different behaviors, depending on the surfactant polar head. In LEC-GMS systems, LEC hindered the self-assembly of GMS in sunflower oil, compromising mechanical properties and increasing oil release. When combined with SMS, LEC acted as a crystal habit modifier of SMS, forming a more homogeneous microstructure and producing stronger oleogels with greater oil binding capacity. However, above the threshold concentration, LEC prevented SMS self-assembly, resulting in a weaker gel. A positive interaction was found in LEC-SAC formulations in specific ratios, since SAC cannot act as a single oleogelator. Results show the impact of solubility balance played by LEC and fatty-acid derivatives surfactant when combined and used as oleogelators. This knowledge can contribute to a rational perspective in the preparation and modulation of the properties of edible oleogels.

Asunto(s)

Lecitinas , Compuestos Orgánicos , Reología , Aceite de Girasol , Tensoactivos , Lecitinas/química , Compuestos Orgánicos/química , Aceite de Girasol/química , Tensoactivos/química , Hexosas/química , Sustitutos de Grasa/química , Glicéridos/química , Sacarosa/química

RESUMEN

PURPOSE: Bevacizumab (BCZ) is a recombinant monoclonal antibody that inhibits the biological activity of the vascular endothelial growth factor, which has an important role in angiogenesis for tumoral growth and progression. In this way, our objective was to develop chitosan-coated lipid-core nanocapsules functionalized with BCZ by an organometallic complex using gold-III. METHODS: The formulation was produced and characterized in relation to physicochemical characteristics. Furthermore, the antitumoral and antiangiogenic activities were evaluated against C6 glioma cell line and chicken embryo chorioallantoic membrane (CAM), respectively. RESULTS: Final formulation showed nanometric size, narrow polydispersity, positive zeta potential and gold clusters size lower than 2 nm. BCZ in aqueous solution (0.01-0.10 µmol L-1) did not show cytotoxic activity in vitro against C6 glioma cell line; although, MLNC-Au-BCZ showed cytotoxicity with a median inhibition concentration of 30 nmol L-1 of BCZ. Moreover, MLNC-Au-BCZ demonstrated cellular internalization dependent on incubation time and BCZ concentration. BCZ solution did not induce significant apoptosis as compared to MLNC-Au-BCZ within 24 h of treatment. CAM assay evidenced potent antiangiogenic activity for MLNC-Au-BCZ, representing a decrease of 5.6 times in BCZ dose comparing to BCZ solution. CONCLUSION: MLNC-Au-BCZ is a promising product for the treatment of solid tumors.

Asunto(s)

Inhibidores de la Angiogénesis/química , Bevacizumab/química , Quitosano/química , Glioma/tratamiento farmacológico , Oro/química , Lípidos/química , Nanocápsulas/química , Inhibidores de la Angiogénesis/farmacología , Animales , Apoptosis/efectos de los fármacos , Bevacizumab/metabolismo , Línea Celular Tumoral , Permeabilidad de la Membrana Celular , Embrión de Pollo , Membrana Corioalantoides/efectos de los fármacos , Complejos de Coordinación/química , Relación Dosis-Respuesta a Droga , Composición de Medicamentos/métodos , Hexosas/química , Humanos , Lectinas de Plantas/química , Polisorbatos/química , Proteínas de Soja/química , Propiedades de Superficie , Factor A de Crecimiento Endotelial Vascular/metabolismo

RESUMEN

Second generation ethanol has the prospect of becoming an important bioenergy alternative. The development of this technology is associated with the lignocellulosic materials' use, with emphasis on agricultural and agroindustrial by-products from which fermentable sugar can be produced. The acid hydrolysis depolymerizes the hemicellulose releasing mainly xylose. Subsequently, the cellulose can be converted into glucose by enzymatic hydrolysis. However, the acid hydrolysis produces toxic compounds, such as furan derivatives, phenolics, and organic acids, which are harmful to fermentative microorganisms. This study investigated different acid concentrations in the sulfuric acid hydrolysis of sugarcane bagasse (1- 5% m/v) and the use of adsorbents with the prerogative to improve the acid hydrolysate (AH) quality for microbial ethanolic fermentation. Cell growth and fermentative yield of Saccharomyces cerevisiae (PE-2) and Scheffersomyces stipitis (NRRL Y-7124) were evaluated. AH was used as a source of pentoses (17.7 g L-1) and molasses (ME) sugarcane as source of hexoses (47 g L-1). The following adsorbents were used: activated charcoal, clay, hydrotalcite and active and inactive cells of PE-2 and NRRL Y-7124, at concentrations ranging (1 - 8% m/v). Results of cell growth and chemical characterization allowed to select the most effective adsorbents with emphasis for active cells that removed 66% furfural and 51% 5-(hydroxymethyl) furfural) (5-HMF) and alcoholic productivity of 23.5 g L-1 in AH and ME substrates, in the presence of mixed culture. These results indicate the application of active yeast cells in the detoxification of acid hydrolysates of the sugarcane bagasse previously to the fermentation.

Asunto(s)

Celulosa/análisis , Saccharomyces cerevisiae/crecimiento & desarrollo , Saccharomycetales/crecimiento & desarrollo , Saccharum/microbiología , Adsorción , Hidróxido de Aluminio/química , Carbón Orgánico/química , Fermentación , Hexosas/química , Hidróxido de Magnesio/química , Pentosas/química , Saccharum/química

RESUMEN

The effects of pH (3.5, 4.5, and 5.5) and UV-C irradiation dose (12.8, 24.2, 35.8, and 54.6 mJ/cm2) on the physicochemical properties changes in 10% Aloe vera gel blends; in addition, the acemannan concentration and structural changes in the precipitated polysaccharides were evaluated. A thermal treatment (TT; 45 s at 90 °C) was used for comparison. In contrast to TT, a dose of 24.2 mJ/cm2 did not induce significant changes of free sugar content. Moreover, TT and UV-C irradiation did not significantly affect the content of mannose but increased those of galactose, fructose, and glucose. 1H NMR analysis revealed minimal changes in the isolated fractions of acemannan, indicating that compared to the unprocessed control sample, the acemannan deacetylation was more pronounced by TT (27%) than by UV-C irradiation (11% at 54.6 mJ/cm2), without any significant difference between the two. UV-C irradiation of Aloe vera gel blends at pH 3.5 and 24.2 mJ/cm2 was an alternative to TT and efficiently preserve the characteristics of acemannan.

Asunto(s)

Aloe/química , Geles/química , Mananos/química , Preparaciones de Plantas/química , Geles/efectos de la radiación , Calefacción , Hexosas/química , Concentración de Iones de Hidrógeno , Mananos/efectos de la radiación , Peso Molecular , Preparaciones de Plantas/efectos de la radiación , Sacarosa/química , Rayos Ultravioleta

RESUMEN

Fungal resistance is the major problem related to fluconazole treatments. This study aims to develop innovative lipid core nanocapsules and nanostructured lipid carriers containing fluconazole, to study in vitro antifungal activity and to assess the possibility of resistance reversion in Candida albicans, C. glabrata, C. krusei, and C. tropicalis isolates. The action mechanism of nanoparticles was investigated through efflux pumps and scanning electron microscopy studies. The lipid core nanocapsules and nanostructured lipid carriers were prepared by interfacial deposition of preformed polymer and high-pressure homogenization methods, respectively. Both nanostructures presented sizes below 250 nm, SPAN < 1.6, negative zeta potential, pH slightly acid, high drug content and controlled drug release. The nanostructured lipid carriers were unable to reverse the fungal resistance. Lipid core nanoparticles displayed advantages such as a reduction in the effective dose of fluconazole and resistance reversion in all isolates tested - with multiple mechanisms of resistance. The main role of the supramolecular structure and the composition of the nanoparticles on antifungal mechanisms of action were discussed. The results achieved through this study have an impact on clinical therapy, with a potential application in the treatment of fungal infections caused by resistant isolates of Candida spp.

Asunto(s)

Antifúngicos/farmacología , Candida/efectos de los fármacos , Preparaciones de Acción Retardada/química , Farmacorresistencia Fúngica/efectos de los fármacos , Fluconazol/farmacología , Proteínas Fúngicas/antagonistas & inhibidores , Nanopartículas/química , Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Candida/genética , Candida/crecimiento & desarrollo , Candida/metabolismo , Candida albicans/efectos de los fármacos , Candida albicans/genética , Candida albicans/crecimiento & desarrollo , Candida albicans/metabolismo , Candida glabrata/efectos de los fármacos , Candida glabrata/genética , Candida glabrata/crecimiento & desarrollo , Candida glabrata/metabolismo , Candida tropicalis/efectos de los fármacos , Candida tropicalis/genética , Candida tropicalis/crecimiento & desarrollo , Candida tropicalis/metabolismo , Caprilatos/química , Composición de Medicamentos/métodos , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expresión Génica , Genes MDR/efectos de los fármacos , Hexosas/química , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Nanopartículas/ultraestructura , Palmitatos/química , Tamaño de la Partícula , Triglicéridos/química , Verapamilo/farmacología

RESUMEN

Coenzyme Q10 (CoQ10) is a mitochondrial respiratory cofactor and potent endogenous antioxidant. In CoQ10-deficient patients, early treatment with high-oral doses (5-50 mg/kg/day) can limit the progression of renal disease and the onset of neurological manifestations. Crystalline CoQ10 is lipophilic, water-insoluble, and poorly absorbed in the gut. Here, CoQ10 showed low bulk density, another important disadvantage in solid oral formulations. Thus, we propose the use of oleogels to maintain dissolved a high-dose of CoQ10 in medium-chain triglyceride (MCT) oil, using ethylcellulose (EC) for gelling, and a surfactant (sorbitan monostearate -SMS- or lecithin). "True gels" were only obtained with the surfactant presence. Thermoreversible oleogels with 1 g of dissolved CoQ10 per 5 g-disk were successfully developed with proved stability and solubility for 12 months (25.0 °C). SMS was better than lecithin as a surfactant because it allowed lower syneresis, higher CoQ10 retention for 12 months, and notably higher oxidative-stability of the MCT-oil, best immobilized by its true gel network. Plastic deformation without fracture was determined under compression, emulating the soft deformation behavior inside the mouth. SMS-oleogels allowed loading a maximal solubilized CoQ10 dose with maximal stability, and may be easier to swallow by CoQ10-deficient patients who suffer from secondary dysphagia.

Asunto(s)

Antioxidantes/administración & dosificación , Celulosa/análogos & derivados , Tensoactivos/química , Ubiquinona/análogos & derivados , Administración Oral , Antioxidantes/química , Celulosa/química , Química Farmacéutica/métodos , Relación Dosis-Respuesta a Droga , Estabilidad de Medicamentos , Hexosas/química , Lecitinas/química , Compuestos Orgánicos , Solubilidad , Triglicéridos/química , Ubiquinona/administración & dosificación , Ubiquinona/química

RESUMEN

The electron paramagnetic resonance (EPR) spin labeling methodology was used to analyze the interactions of phosphatidylcholine (PC) liposomal formulations that are commonly used as transepidermal drug delivery systems with stratum corneum (SC) membranes. The lipid dynamics of five liposome formulations were evaluated to study the influences of sorbitan monooleate (Span80), cholesterol, and cholesterol with the charged lipids 2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-distearoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DSPG) on the molecular dynamics of PC vesicles. The EPR spectra of 5-doxyl-stearic acid (5-DSA) showed that the addition of Span80 to the liposomes increased the lipid fluidity, whereas cholesterol had the opposite effect, and the combination of charged lipids and cholesterol did not additionally influence the lipid bilayer dynamics. Fatty acid spin-labeled SC membranes were treated with the liposome formulations, leading to migration of the spin label to the molecular environment of the formulation and the presence of two spectral components representing distinct mobility states. In terms of molecular dynamics, these environments correspond to the lipid domains of the untreated SC and the liposome, indicating a poor interaction between the liposome and SC membranes. However, the contact was sufficient to allow a pronounced exchange of the spin-labeled fatty acid. Our data suggest that flexible liposomes may access the inner intercellular membranes of the SC and facilitate mutual lipid exchange without losing their relative liposomal integrity.

Asunto(s)

Espectroscopía de Resonancia por Spin del Electrón , Fosfatidilcolinas/metabolismo , Absorción Cutánea , Piel/metabolismo , Animales , Animales Recién Nacidos , Colesterol/química , Colesterol/metabolismo , Composición de Medicamentos , Ácidos Grasos Monoinsaturados/química , Ácidos Grasos Monoinsaturados/metabolismo , Hexosas/química , Hexosas/metabolismo , Liposomas , Simulación de Dinámica Molecular , Fosfatidilcolinas/química , Fosfatidilgliceroles/química , Fosfatidilgliceroles/metabolismo , Compuestos de Amonio Cuaternario/química , Compuestos de Amonio Cuaternario/metabolismo , Ratas Wistar , Tecnología Farmacéutica/métodos

RESUMEN

Studies employing Cecropia glaziovii Snethl leaves have shown great potential in regard to their antiviral activity, mainly related to the phenolic compounds present in this species. The main goal of this work is to combine the therapeutic potential of this species with new technological strategies targeted at the development of an herbal nanoparticulate system for the preparation of a phytotherapeutic formulation. Poly (lactic-co-glycolic acid) nanoparticles containing the enriched flavonoid fraction of Cecropia glaziovii Snethl were developed through a study for the choice of preparation technique, amount of drug and surfactants used. These nanostructured systems were characterized by particle size, polydispersity, zeta potential, encapsulation efficiency and drug-loading capacity. A stability study of the formulations was conducted at room temperature over a period of 60 days. The optimal formulation that best fit the characteristics of the encapsulated material was determined. Sorbitan monooleate and the poloxamer 188 resulted in better colloidal stability, added to the organic and aqueous phases, respectively. These findings suggest that in the field of nanoparticles stability, it is important to evaluate the composition of the nanoparticulate system. This work highlights the importance of the optimization process, searching for a good formulation with suitable structural stabilization.

Asunto(s)

Cecropia/química , Portadores de Fármacos/química , Flavonoides/administración & dosificación , Nanopartículas/química , Extractos Vegetales/administración & dosificación , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Liberación de Fármacos , Estabilidad de Medicamentos , Flavonoides/química , Flavonoides/aislamiento & purificación , Hexosas/química , Tamaño de la Partícula , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Poloxámero/química , Solubilidad , Tensoactivos/química

RESUMEN

Nanoemulsions are feasible delivery systems of lipophilic compounds, showing potential as edible coatings with enhanced functional properties. The aim of this work was to study the effect of emulsifier type (stearic acid (SA), Tween 80 (T80) or Tween 80/Span 60 (T80/S60)) and emulsification process (homogenization, ultrasound or microfluidization) on nanoemulsion formation based on oxidized corn starch, beeswax (BW) and natural antimicrobials (lauric arginate and natamycin). The response variables were physicochemical properties, rheological behavior, wettability and antimicrobial activity of BW-starch nanoemulsions (BW-SN). The BW-SN emulsified using T80 and microfluidized showed the lowest droplet size (77.6 ± 6.2 nm), a polydispersion index of 0.4 ± 0.0 and whiteness index (WI) of 31.8 ± 0.8. This BW-SN exhibited a more negative ζ-potential: -36 ± 4 mV, and Newtonian flow behavior, indicating great stability. BW-SN antimicrobial activity was not affected by microfluidization nor the presence of T80, showing inhibition of the deteriorative fungi R. stolonifer, C. gloeosporioides and B. cinerea, and the pathogenic bacterium S. Saintpaul. In addition, regardless of emulsifier type and emulsification process, BW-SN applied on the tomato surface exhibited low contact angles (38.5° to 48.6°), resulting in efficient wettability (-7.0 mN/m to -8.9 mN/m). These nanoemulsions may be useful to produce edible coatings to preserve fresh-produce quality and safety.

Asunto(s)

Antiinfecciosos/uso terapéutico , Sistemas de Liberación de Medicamentos , Nanocompuestos/química , Ceras/química , Antiinfecciosos/química , Emulsiones/química , Emulsiones/uso terapéutico , Hexosas/química , Hexosas/uso terapéutico , Humanos , Nanocompuestos/uso terapéutico , Polisorbatos/química , Polisorbatos/uso terapéutico , Almidón/química , Almidón/uso terapéutico , Ácidos Esteáricos/química , Ácidos Esteáricos/uso terapéutico

RESUMEN

Polyphenols, which are secondary plant metabolites, gain increasing research interest due to their therapeutic potential. Among them, resveratrol and curcumin are two agents showing antioxidant, anti-inflammatory, antimicrobial as well as anticarcinogenic effects. In addition to their individual therapeutic effect, increased activity was reported upon co-delivery of the two compounds. However, due to the poor water solubility of resveratrol and curcumin, their clinical application is currently limited. In this context, lipid-core nanocapsules (LNC) composed of an oily core surrounded by a polymeric shell were introduced as drug carrier systems with the potential to overcome this obstacle. Furthermore, the encapsulation of polyphenols into LNC can increase their photostability. As the attributes of the polyphenols make them excellent candidates for skin treatment, the aim of this study was to investigate the effect of co-delivery of resveratrol and curcumin by LNC upon topical application on excised human skin. In contrast to the formulation with one polyphenol, resveratrol penetrated into deeper skin layers when the co-formulation was applied. Based on vibrational spectroscopy analysis, these effects are most likely due to interactions of curcumin and the stratum corneum, facilitating the skin absorption of the co-administered resveratrol. Furthermore, the interaction of LNC with primary human skin cells was analyzed encountering a cellular uptake within 24h potentially leading to intracellular effects of the polyphenols. Thus, the simultaneous delivery of resveratrol and curcumin by LNC provides an intelligent way for immediate and sustained polyphenol delivery for skin disease treatment.

Asunto(s)

Curcumina/administración & dosificación , Portadores de Fármacos/administración & dosificación , Nanocápsulas/administración & dosificación , Absorción Cutánea , Estilbenos/administración & dosificación , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Curcumina/química , Portadores de Fármacos/química , Liberación de Fármacos , Fibroblastos/efectos de los fármacos , Extracto de Semillas de Uva/administración & dosificación , Extracto de Semillas de Uva/química , Hexosas/administración & dosificación , Hexosas/química , Humanos , Técnicas In Vitro , Nanocápsulas/química , Aceites/administración & dosificación , Aceites/química , Poliésteres/administración & dosificación , Poliésteres/química , Polifenoles/administración & dosificación , Polifenoles/química , Resveratrol , Estilbenos/química

RESUMEN

Resveratrol and curcumin are two natural polyphenols extensively used due to their remarkable anti-inflammatory activity. The present work presents an inedited study of the in vivo antioedematogenic activity of these polyphenols co-encapsulated in lipid-core nanocapsules on Complete Freund's adjuvant (CFA)-induced arthritis in rats. Lipid-core nanocapsules were prepared by interfacial deposition of preformed polymer. Animals received a single subplantar injection of CFA in the right paw. Fourteen days after arthritis induction, they were treated with resveratrol, curcumin, or both in solution or loaded in lipid-core nanocapsules (1.75 mg/kg/twice daily, i.p.), for 8 days. At the doses used, the polyphenols in solution were not able to decrease paw oedema. However, nanoencapsulation improved the antioedematogenic activity of polyphenols at the same doses. In addition, the treatment with co-encapsulated polyphenols showed the most pronounced effects, where an inhibition of 37-55% was observed between day 16 and 22 after arthritis induction. This treatment minimized most of the histological changes observed, like fibrosis in synovial tissue, cartilage and bone loss. In addition, unlike conventionally arthritis treatment, resveratrol and curcumin co-encapsulated in lipid-core nanocapsules did not alter important hepatic biochemical markers (ALP, AST, and ALT). In conclusion, the strategy of co-encapsulating resveratrol and curcumin in lipid-core nanocapsules improves their efficacy as oedematogenic agents, with no evidence of hepatotoxic effects. This is a promising strategy for the development of new schemes for treatment of chronic inflammation diseases, like arthritis.

Asunto(s)

Antiinflamatorios/administración & dosificación , Artritis Experimental/tratamiento farmacológico , Curcumina/administración & dosificación , Portadores de Fármacos/administración & dosificación , Nanocápsulas/administración & dosificación , Estilbenos/administración & dosificación , Animales , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Artritis Experimental/patología , Curcumina/química , Curcumina/uso terapéutico , Portadores de Fármacos/química , Portadores de Fármacos/uso terapéutico , Articulaciones del Pie/patología , Extracto de Semillas de Uva/química , Hexosas/química , Inyecciones Intraperitoneales , Masculino , Nanocápsulas/química , Nanocápsulas/uso terapéutico , Poliésteres/química , Polisorbatos/química , Ratas Wistar , Resveratrol , Estilbenos/química , Estilbenos/uso terapéutico , Resultado del Tratamiento

RESUMEN

BACKGROUND: The aim of this study was to develop and characterize a babassu oil microemulsion system and determine the effect of this microemulsion on the functional activity of phagocytes. METHODS: The microemulsion was formulated using distilled water, babassu as the oil phase component, Sorbitan monooleate-Span 80(®) (SP), Polysorbate 80-Tween 80(®) (TW), and 1-butanol (BT). Pseudoternary diagrams were prepared, and microemulsion diagram regions were preselected. Rheological characterization and preliminary and accelerated stability tests were performed. The effect of the microemulsion on the interactions between leukocytes and bacteria was determined by superoxide release, phagocytosis, and microbicidal activity. RESULTS: The developed formulation SP/TW/BT (4.2/4.8/1.0) was classified as oil/water, showed a Newtonian profile, and had linear viscosity. When we assessed the interaction of the microemulsion or babassu oil with phagocytes, we observed an increase in superoxide, phagocytosis, and microbicidal activity. CONCLUSION: The babassu oil microemulsion system is an option for future applications, including for vaccine delivery systems. Babassu oil is a natural product, so is an alternative for future immunotherapy strategies, in particular for infectious diseases.

Asunto(s)

Antibacterianos/farmacología , Productos Biológicos/farmacología , Sistema Inmunológico/efectos de los fármacos , Sistema Inmunológico/inmunología , Aceites de Plantas/farmacología , 1-Butanol/química , 1-Butanol/farmacología , Antibacterianos/química , Productos Biológicos/química , Emulsiones/química , Emulsiones/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Hexosas/química , Hexosas/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Fagocitos/efectos de los fármacos , Fagocitos/inmunología , Fagocitosis/efectos de los fármacos , Fagocitosis/inmunología , Aceites de Plantas/química , Polisorbatos/química , Polisorbatos/farmacología , Reología , Superóxidos/inmunología

RESUMEN

BACKGROUND: Nanoemulsions have practical application in a multitude of commercial areas, such as the chemical, pharmaceutical and cosmetic industries. Cosmetic industries use rice bran oil in sunscreen formulations, anti ageing products and in treatments for skin diseases. The aim of this study was to create rice bran oil nanoemulsions using low energy emulsification methods and to evaluate their physical stability, irritation potential and moisturising activity on volunteers with normal and diseased skin types. RESULTS: The nanoemulsion developed by this phase diagram method was composed of 10% rice bran oil, 10% surfactants sorbitan oleate/PEG-30 castor oil, 0.05% antioxidant and 0.50% preservatives formulated in distilled water. The nanoemulsion was stable over the time course of this study. In vitro assays showed that this formulation has a low irritation potential, and when applied to human skin during in vivo studies, the nanoemulsion improved the skin's moisture and maintained normal skin pH values. CONCLUSION: The results of irritation potential studies and in vivo assessments indicate that this nanoemulsion has potential to be a useful tool to treat skin diseases, such as atopic dermatitis and psoriasis.

Asunto(s)

Emulsiones/química , Nanotecnología , Aceites de Plantas/química , Agua/química , Administración Tópica , Adulto , Antioxidantes/química , Aceite de Ricino/química , Química Farmacéutica , Estabilidad de Medicamentos , Conductividad Eléctrica , Emulsiones/farmacología , Femenino , Hexosas/química , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad , Tamaño de la Partícula , Psoriasis/terapia , Aceite de Salvado de Arroz , Piel/efectos de los fármacos , Piel/metabolismo , Absorción Cutánea , Adulto Joven

RESUMEN

The aims of this work were to increase the photostability and to reduce the skin permeation of tretinoin through nanoencapsulation. Tretinoin is widely used in the topical treatment of various dermatological diseases such as acne, psoriasis, skin cancer, and photoaging. Tretinoin-loaded lipid-core polymeric nanocapsules were prepared by interfacial deposition of a preformed polymer. Carbopol hydrogels containing nanoencapsulated tretinoin presented a pH value of 6.08±0.14, a drug content of 0.52±0.01 mg g(-1), pseudoplastic rheological behavior, and higher spreadability than a marketed formulation. Hydrogels containing nanoencapsulated tretinoin demonstrated a lower photodegradation (24.17±3.49%) than the formulation containing the non-encapsulated drug (68.64±2.92%) after 8h of ultraviolet A irradiation. The half-life of the former was seven times higher than the latter. There was a decrease in the skin permeability coefficient of the drug by nanoencapsulation, independently of the dosage form. The liquid suspension and the semisolid form provided K(p)=0.31±0.15 and K(p)=0.33±0.01 cm s(-1), respectively (p≤0.05), while the samples containing non-encapsulated tretinoin showed K(p)=1.80±0.27 and K(p)=0.73±0.12 cm s(-1) for tretinoin solution and hydrogel, respectively. Lag time was increased two times by nanoencapsulation, meaning that the drug is retained for a longer time on the skin surface.

Asunto(s)

Portadores de Fármacos/química , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos , Queratolíticos/química , Nanocápsulas/química , Tretinoina/química , Abdomen/fisiología , Administración Tópica , Adulto , Portadores de Fármacos/administración & dosificación , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Excipientes/química , Femenino , Hexosas/química , Humanos , Hidrogeles/administración & dosificación , Hidrogeles/química , Queratolíticos/administración & dosificación , Lípidos , Tamaño de la Partícula , Permeabilidad , Fotólisis , Poliésteres/química , Poliésteres/metabolismo , Polímeros/química , Piel , Suspensiones , Tretinoina/administración & dosificación , Tretinoina/metabolismo

RESUMEN

Carapa guianensis, a popular medicinal plant known as "Andiroba" in Brazil, has been used in traditional medicine as an insect repellent and anti-inflammatory product. Additionally, this seed oil has been reported in the literature as a repellent against Aedes aegypti. The aim of this work is to report on the emulsification of vegetable oils such as "Andiroba" oil by using a blend of nonionic surfactants (Span 80® and Tween 20®), using the critical hydrophilic-lipophilic balance (HLB) and pseudo-ternary diagram as tools to evaluate the system's stability. The emulsions were prepared by the inverse phase method. Several formulations were made according to a HLB spreadsheet design (from 4.3 to 16.7), and the products were stored at 25°C and 4°C. The emulsion stabilities were tested both long- and short-term, and the more stable one was used for the pseudo-ternary diagram study. The emulsions were successfully obtained by a couple of surfactants, and the HLB analysis showed that the required HLB of the oil was 16.7. To conclude, the pseudo-ternary diagram identified several characteristic regions such as emulsion, micro-emulsion, and separation of phases.

Asunto(s)

Emulsiones/síntesis química , Hexosas/química , Meliaceae/química , Aceites de Plantas/química , Polisorbatos/química , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Almacenaje de Medicamentos

RESUMEN

A bio-guided screening against influenza A virus (FLUAV) was carried out with seven Euphorbiaceae species. The results showed that chromatographic fractions from Phyllantus niruri, Euphorbia pulcherrima and Codiaeum variegatum had relevant anti-FLUAV activity, although only chromatographical subfractions from C. variegatum kept the activity. From this plant, the active compound against FLUAV was isolated. Its structure was assigned as 2-(3,4,5)-trihydroxy-6-hydroxymethyltetrahydropyran-2-yloxymethyl)acrylonitrile (1) on the basis of NMR, mass spectrometry and X-ray diffraction analysis. The compound displayed virucidal activity without impairment of haemagglutination properties of the used virus strain. This is the first report indicating antiviral activity of a cyanoglucoside.

Asunto(s)

Acrilonitrilo/análogos & derivados , Antivirales/farmacología , Euphorbiaceae/química , Glucósidos/farmacología , Hexosas/farmacología , Virus de la Influenza A/efectos de los fármacos , Acrilonitrilo/química , Acrilonitrilo/aislamiento & purificación , Acrilonitrilo/farmacología , Animales , Antivirales/química , Antivirales/aislamiento & purificación , Línea Celular , Perros , Glucósidos/química , Glucósidos/aislamiento & purificación , Hexosas/química , Hexosas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Resonancia Magnética Nuclear Biomolecular , Difracción de Rayos X

RESUMEN

Burkholderia brasiliensis, a Gram-negative diazotrophic endophytic bacterium, was first isolated from roots, stems, and leaves of rice plant in Brazil. The polysaccharide moiety was released by ammonolysis from the B. brasiliensis lipopolysaccharide (LPS), allowing the unambiguous characterization of a 3,6-dideoxy-4-C-(1-hydroxyethyl)-D-xylo-hexose (yersiniose A), an uncommon feature for Burkholderia LPS. The complete structure of the yersiniose A-containing O-antigen was identified by sugar and methylation analyses and NMR spectroscopy. Our results show that the repeating oligosaccharide motif of LPS O-chain consists of a branched tetrasaccharide with the following structure:-->2-alpha-d-Rhap-(1-->3)-[alpha-YerAp-(1-->2)]-alpha-D-Rhap-(1-->3)-alpha-D-Rhap-(1-->.

Asunto(s)

Burkholderia/metabolismo , Hexosas/metabolismo , Nitrógeno/metabolismo , Antígenos O/química , Antígenos O/metabolismo , Burkholderia/química , Secuencia de Carbohidratos , Cromatografía en Gel , Hexosas/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Datos de Secuencia Molecular