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1.
Acta Virol ; 63(3): 316-321, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507198

RESUMO

The recent Zika virus (ZIKV) outbreaks and rapid spread in tropical Latin America since introduction to Brazil in 2014, and now appearing cases in the USA, are alarming. World Health Organization (WHO) has considered transmission of ZIKV, a serious public health problem because of the increasing number of outbreaks. There are currently no drugs approved for the treatment of ZIKV infection. Discovery of safe and effective drugs are hampered by the risk in treating pregnant woman and toxicity to the fetus. Sweet basil, known as Ocimum basilicum in the scientific community, is a very well-known medicinal herb. Numerous studies have documented its beneficial activity against a great variety of human pathogens ranging from bacteria and virus to fungus and protozoans. Although, basil extracts and oils have been tested successfully against other viruses, its application to tackle ZIKV infection has not been exploited at all. In this study, we report for the first time that highly diluted ethanol extracts prepared from basil leaves can effectively inhibit ZIKV replication in Vero E6 cells with a half maximal inhibitory concentration (IC50) value of 1:134. The diluted extract as well as the amount of ethanol that goes into its preparation have been found to be completely non-toxic to the above mentioned cell line. The extract seems to inhibit the virus at the step of attachment and entry into the host cell. The specific inhibition of ZIKV observed using the basil leaf extract suggests a new alternative mode of treatment against flavivirus. Keywords: Zika virus; basil extract; antiviral.


Assuntos
Ocimum basilicum , Extratos Vegetais , Internalização do Vírus , Infecção por Zika virus , Animais , Sobrevivência Celular/efeitos dos fármacos , Cercopithecus aethiops , Etanol/química , Ocimum basilicum/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Plantas Medicinais/química , Células Vero , Internalização do Vírus/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Zika virus/fisiologia
2.
Bioresour Technol ; 291: 121844, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31400704

RESUMO

A low-temperature sodium hydroxide (NaOH) pretreatment for sugarcane bagasse (SCB) was obtained via the surface response design in this study. However, a large quantity of water consumption and wastewater generation which have been the common problems for alkaline pretreatment of lignocellulose still exists in this pretreatment. In order to reduce water consumption and wastewater generation, this study attempted to perform enzymatic hydrolysis and fermentation of NaOH-treated SCB without washing process. It showed that after pretreatment and solid-liquid separation, NaOH-treated SCB could be directly hydrolysed by cellulase via pH and solid-liquid adjustment without washing steps, and the maximum enzymatic hydrolysis efficiency could reach to 70.2%. A domesticated Saccharomyces cerevisiae Y2034 which can endure 6-times diluted BL was obtained, and realized 67.5% ethanol yield from the enzymatic hydrolysate of unwashed NaOH-treated SCB. It provided a clue for converting NaOH-treated lignocellulose to ethanol at low water consumption and wastewater generation.


Assuntos
Celulose/química , Etanol/química , Saccharum/química , Hidróxido de Sódio/química , Celulose/metabolismo , Temperatura Baixa , Etanol/metabolismo , Fermentação , Hidrólise , Lignina/química , Lignina/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharum/metabolismo , Águas Residuárias/química
3.
Food Chem ; 300: 125174, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31330370

RESUMO

This paper focuses on the use of a new type of yeast encapsulation procedure, applying the chitosan-calcium alginate double layer microcapsules, for the production of Riesling sparkling wine. Four different sparkling wines were produced by free or encapsulated yeasts. The four types of yeast used were adapted (Free EtOH-A, Encapsulated EtOH-A) and non-adapted to ethanol (Free, Encapsulated). The different yeast-inoculating formats had a significant impact on oxygen consumption and pressure increase rate in the bottle during the prise de mousse. Similarly to the free form, encapsulated yeast successfully completed the secondary fermentation. After an ageing period of 6 months, volatiles and sensory profiles of sparkling wines were compared. Although, some differences in volatile profiles were found among samples, sparkling wines produced by Encapsulated EtOH-A showed sensory properties, in terms of aroma, taste and body, similar to those produced by free yeast (both adapted and non-adapted to ethanol).


Assuntos
Alginatos/química , Quitosana/química , Saccharomyces cerevisiae/fisiologia , Vinho/microbiologia , Adulto , Idoso , Cápsulas , Etanol/química , Etanol/farmacologia , Feminino , Fermentação , Humanos , Masculino , Pessoa de Meia-Idade , Odorantes , Pressão , Saccharomyces cerevisiae/efeitos dos fármacos , Paladar , Compostos Orgânicos Voláteis/análise , Vinho/análise
4.
Food Chem ; 300: 125191, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31352290

RESUMO

Viscosity is a property that exerts great influence on the body of wines, since it affects the sensation of thickness in the mouth. The present study refers to the quantitative correlation of the major components of wine, alcohol, reduced sugar, glycerol and total acidity, in its viscosity. Various model aqueous solutions consisting of these components were prepared and viscosity was measured at 20 °C. Each component was studied either alone or in mixtures with the others. Viscosity of white dry wines samples was also measured. From the experimental results, linear multi-dependence equations were derived, which correlate the viscosity with the concentration of the components of the solutions, each of them alone and in combination. Glucose was found to affect viscosity of model aqueous solutions the most, whereas ethanol had the least effect. The knowledge of these factors may have a practical value in optimizing wine's body.


Assuntos
Etanol/química , Glucose/química , Glicerol/química , Tartaratos/química , Vinho , Modelos Químicos , Soluções/química , Viscosidade , Água , Vinho/análise
5.
Food Chem ; 300: 125217, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351255

RESUMO

In this study, lecithin obtained from acid degumming of canola oil was fractionated with absolute ethanol. The lipid composition and emulsifying properties of the resulting fractions were investigated. The results showed that phosphatidylcholine and lyso-phosphatidylcholine were greatly enriched in the ethanol soluble fraction (ESF), accounting for 43.79% and 13.21% of ESF, respectively. Phosphatidylinositol, lyso-phosphatidylinositol and phosphatidic acid, as a group, were enriched in the ethanol insoluble fraction (EIF), accounting for 37.4% of EIF. ESF and EIF promoted oil/water (o/w) emulsions as stable as the parent canola lecithin. EIF was not better than the parent lecithin as w/o emulsifier. This information is critical for evaluating the potential utilization of these canola lecithin fractions as emulsifiers or sources of specific phospholipid.


Assuntos
Emulsificantes/química , Lecitinas/química , Fosfolipídeos/química , Óleo de Brassica napus/química , Fracionamento Químico , Emulsões/química , Etanol/química , Fosfatidilinositóis/química
6.
Bioresour Technol ; 291: 121805, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31351376

RESUMO

With a view to boost practical implementation of lignin conversion technologies, this paper assesses the availability of industrial lignin and evaluates pricing strategies applicable to multi-product biorefineries. The biorefineries, producing either denatured ethanol or sugar hydrolysate as a main product, can yield 43% and 61% of lignin residue (LR) comprising 33% and 23% of lignin by mass, respectively, without sacrificing the output of the main product and before electricity import has become indispensable. Analysis of the pricing strategies reveals that LR must be treated as a low-value by-product, and its minimum selling price (MSP) is driven mainly by the prevailing electricity price. Under the biorefinery net zero energy balance, and taking into account the LR market price adequacy, as well as the main probabilistic conditions, the upper range for the MSP is calculated at $43-70 and $18-37 per ton for biorefineries producing ethanol and hydrolysate, respectively.


Assuntos
Lignina/química , Custos e Análise de Custo , Eletricidade , Etanol/química , Indústrias , Lignina/economia
7.
Anticancer Res ; 39(7): 3697-3709, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262896

RESUMO

BACKGROUND/AIM: Cervical cancer is considered poorly chemo-sensitive in women and its treatment remains unsatisfactory. Cyperus rotundus is used in Chinese medicine as a therapeutic agent for women's disease. The effects and molecular mechanisms of the ethanol extraction of C. rotundus (CRE) on cervical cancer remain unclear. We aimed to explore the mechanisms and genetic influence of CRE on cervical cancer. MATERIALS AND METHODS: HeLa, human cervical cancer cells were treated with various doses of CRE and changes in cell morphology and cell viability were assessed using microscopy and flow cytometry. Finally, we performed a microarray analysis to scan related genes. RESULTS: The treatment of CRE on HeLa cells caused morphological changes and induced chromatin condensation. DNA microarray analysis showed that CRE led to up-regulation of 449 genes and down-regulation of 484 genes, which were classified in several interaction pathways. CONCLUSION: CRE changed HeLa cell morphology and induced gene expression which associated with apoptosis and cell-cycle arrest. These results provide important information at the transcription level for targeting treatments of human cervical cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Cyperus , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Neoplasias do Colo do Útero/genética , Apoptose/genética , Ciclo Celular/efeitos dos fármacos , Etanol/química , Feminino , Células HeLa , Humanos , Solventes/química , Neoplasias do Colo do Útero/tratamento farmacológico
8.
Food Chem ; 295: 432-440, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174779

RESUMO

This study examined the effects of vacuum, ethanol pretreatment, and infrared-hot air drying methods on the characteristics and quality of scallion slices. The pretreatment of scallion includes four conditions: 1) Control: soaking in distilled water under normal pressure, 2) Ethanol: soaking in 75% ethanol under normal pressure, 3) Water + VC: soaking in distilled water under a vacuum of 0.6 bar, 4) Ethanol + VC: soaking in 75% ethanol under a vacuum of 0.6 bar. The pretreatment times were 5, 10, 20 and 30 min. The drying process was done in an infrared hot air drying oven at 60 °C. The ethanol pretreated samples exhibited better rehydration, odor, vitamin C retention, bactericidal effect and significantly reduced drying time. Water + VC samples showed better scallion morphology and color. Ethanol + VC samples showed the combined advantages of ethanol and Water + VC pretreatments. Therefore, Ethanol + VC pretreatment can significantly improve the drying rate and quality of scallion.


Assuntos
Allium/química , Manipulação de Alimentos/métodos , Ácido Ascórbico/química , Cor , Dessecação/métodos , Etanol/química , Qualidade dos Alimentos , Temperatura Alta , Raios Infravermelhos , Pressão , Vácuo , Água/química
9.
Food Chem Toxicol ; 131: 110534, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31150781

RESUMO

Acute and subacute toxicities of the ethanol extract from Epigynum auritum (EAE) wereperformed by oral administration in pathogen-free mice. Acute toxicity study was performed at a single dose of 5000 mg/kg for 14 consecutive days, while subacute toxicity test was conducted by daily oral administration of EAE at doses of 312, 625, 1250, and 2500 mg/kg for 28 days. Acute toxicity study showed that LD50 of EAE was over 5000 mg/kg. The results of subacute toxicity showed no significant adverse effect of EAE at 312 mg/kg. Moreover, EAE exhibited toxicities to liver, spleen and kidney in mice determined by hematological, serum biochemical and histological analyses during daily oral administration of 1250 mg/kg and 2500 mg/kg EAE. The results revealed that the dose of EAE lower than 625 mg/kg can be regarded as safe.


Assuntos
Apocynaceae/química , Componentes Aéreos da Planta/química , Extratos Vegetais/toxicidade , Administração Oral , Animais , Relação Dose-Resposta a Droga , Etanol/química , Feminino , Rim/patologia , Fígado/patologia , Pulmão/patologia , Masculino , Camundongos Endogâmicos ICR , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Potássio/sangue , Sódio/sangue , Baço/patologia , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
10.
Protein Pept Lett ; 26(5): 377-385, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31237199

RESUMO

BACKGROUND: Lytic Polysaccharide Monooxygenases (LPMOs) are auxiliary accessory enzymes that act synergistically with cellulases and which are increasingly being used in secondgeneration bioethanol production from biomasses. Several LPMOs have been identified in various filamentous fungi, including Aspergillus fumigatus. However, many LPMOs have not been characterized yet. OBJECTIVE: To report the role of uncharacterized A. fumigatus AfAA9_B LPMO. METHODS: qRT-PCR analysis was employed to analyze the LPMO gene expression profile in different carbon sources. The gene encoding an AfAA9_B (Afu4g07850) was cloned into the vector pET- 28a(+), expressed in the E. coli strain RosettaTM (DE3) pLysS, and purified by a Ni2+-nitrilotriacetic (Ni-NTA) agarose resin. To evaluate the specific LPMO activity, the purified protein peroxidase activity was assessed. The auxiliary LPMO activity was investigated by the synergistic activity in Celluclast 1.5L enzymatic cocktail. RESULTS: LPMO was highly induced in complex biomass like sugarcane bagasse (SEB), Avicel® PH-101, and CM-cellulose. The LPMO gene encoded a protein comprising 250 amino acids, without a CBM domain. After protein purification, the AfAA9_B molecular mass estimated by SDSPAGE was 35 kDa. The purified protein specific peroxidase activity was 8.33 ± 1.9 U g-1. Upon addition to Celluclast 1.5L, Avicel® PH-101 and SEB hydrolysis increased by 18% and 22%, respectively. CONCLUSION: A. fumigatus LPMO is a promising candidate to enhance the currently available enzymatic cocktail and can therefore be used in second-generation ethanol production.


Assuntos
Aspergillus fumigatus/enzimologia , Celulose/química , Proteínas Fúngicas/química , Oxigenases de Função Mista/química , Polissacarídeos/química , Saccharum/química , Biomassa , Escherichia coli/genética , Etanol/química , Proteínas Fúngicas/genética , Hidrólise , Oxirredução , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
11.
J Oleo Sci ; 68(7): 679-687, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31178468

RESUMO

Hydrotalcite or Mg-Al LDHs were synthesized by co-precipitation method. The Mg-Al mixed oxide was then derived by calcination of hydrotalcite at 450°C. The metal modified catalysts (Mo/Mg-Al and V/Mg-Al) were prepared by incipient wetness impregnation method. The obtained catalysts were characterized by several useful techniques and tested the reactivity for dehydrogenation and oxidative dehydrogenation of ethanol (gas-phase) to produce acetaldehyde. The catalytic reactions were performed at temperature range from 200 to 400°C for both non-oxidative and oxidative atmospheres. The results showed that the vanadium-modified hydrotalcite (V/Mg-Al) exhibited the highest ethanol conversion (34.3%) and acetaldehyde yield (15.5%) at 400℃ in the non-oxidative atmosphere. For the oxidative dehydrogenation of ethanol, the V/Mg-Al catalyst showed the highest activity at 400°C giving the ethanol conversion and acetaldehyde yield of 73.7% and 29.5%, respectively. This result probably related to the highest base density of V/Mg-Al catalyst (6.13 µmol CO2/m2) measured by CO2-TPD. The catalytic activity of Mg-Al catalyst and metal modified catalyst slightly decreased upon time-on-stream test for 10 h on oxidative dehydrogenation of ethanol due to carbon deposition.


Assuntos
Compostos de Alumínio/química , Hidróxido de Alumínio/química , Etanol/química , Compostos de Magnésio/química , Hidróxido de Magnésio/química , Molibdênio/química , Vanádio/química , Compostos de Alumínio/síntese química , Hidróxido de Alumínio/síntese química , Carbono , Catálise , Precipitação Química , Temperatura Alta , Hidrogenação , Compostos de Magnésio/síntese química , Hidróxido de Magnésio/síntese química , Oxirredução
12.
J Chromatogr A ; 1602: 48-55, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31147154

RESUMO

One of the major drawbacks of conventional molecularly imprinted polymers (MIPs) is the requirements of volatility porogenic solvent during polymerization. To overcome the default, MIP based on deep eutectic solvent (DES, a new type of green designer solvents) has been synthesized successfully. To improve the affinity of the MIP based on DES, in this work, a strategy of metallic pivot was suggested in the first time to prepare a highly selective MIP monolithic column. A cetirizine-imprinted polymer was prepared in a DES-based porogen system composed of choline chloride/ ethylene glycol (ChCl-EG) in the presence of Co(Ac)2 as metallic pivot. The resulting DES- Co2+-MIP monolith had 23.5 times higher imprinting factor than the Co2+-free MIP monolith. The characterization of polymers indicated that DES was one of the primary factor influencing the MIP morphology and pore structure. Compared with previous metal-mediated and ionic liquid-based imprinted polymers, the introduction of DES as a porogen in polymerization led to higher imprinting factor (approximately 2.9 - 17.1 times). In addition, the resulting DES-Co2+-MIP can be used as an adsorbent for extraction of cetirizine from ethanol solution with the recoveries of 97.8%. As a conclusion, the metallic pivot is a rather valuable strategy for the synthesis of DES-based MIP monolith with high selectivity.


Assuntos
Técnicas de Química Analítica/métodos , Metais/química , Impressão Molecular , Polímeros/síntese química , Solventes/química , Cetirizina/química , Cetirizina/isolamento & purificação , Etanol/química , Etilenoglicol , Polimerização , Polímeros/química
13.
Food Chem ; 295: 156-164, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174744

RESUMO

During ageing, wood adsorbs volatile compounds from beverages. However, chemical interactions involved in sorption still remain unclear, as well as wood capacity to transfer such compounds to subsequent matrices when reused. Therefore, extractions were conducted from used wood manipulating variables such as ethanol concentration, contact temperature and pH, in order to determine their effect in the interaction and consequent recovery of wine volatiles from wood. Mathematical models were outlined, which demonstrated an exclusive effect of ethanol concentration on the extraction of wine volatiles adsorbed in wood, more prominent for compounds of higher hydrophobicity. Thus adsorption of wine volatiles was shown to be based on hydrophobic interactions. Recovery of wood extractives was also modeled, confirming the known positive effect of ethanol and temperature on the overall extraction of characteristic wood compounds. When reused, wood transferred wine compounds to hydroalcoholic matrices, demonstrating its impact and potential as a vector for aroma transference.


Assuntos
Quercus/química , Compostos Orgânicos Voláteis/química , Vinho/análise , Madeira/química , Adsorção , Etanol/química , Concentração de Íons de Hidrogênio , Temperatura Ambiente , Fatores de Tempo
14.
J Photochem Photobiol B ; 197: 111500, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31200215

RESUMO

SCOPE: Overexposure to the ultraviolet radiation may trigger the development of adverse health effects such as the appearance of burns, blemishes, skin aging and skin cancer. These harmful effects on health can be minimized with daily application of photoprotective products or multifunctional products. Medicinal plants may present potential for sun protection and among the species of Brazilian flora, we can highlight the species of the genus Campomanesia. In this context, the photoprotective potential of Campomanesia guazumifolia, Campomanesia sessiliflora, Campomanesia xanthocarpa and Campomanesia adamantium were evaluated. METHODS AND RESULTS: The ethanolic extracts of C. guazumifolia (CG), C. sessiliflora (CS), C. xanthocarpa (CX) and C. adamantium (CA) showed absorption in the UVA and UVB regions. At the concentration of 8%, all the extracts presented sun protection factor (SPF) values higher than 2 and in the concentration of 4% only CA and CX. All plant extracts, alone or in combination, had increased the SPF with the incorporation of octyl methoxynnamate (OM). The samples that presented the highest SPF values contain the association of CA and CX. During the preliminary stability study, the formulations (SSPFOM4, SSPFCX4CA4OM4 and SSPFCX4CA4) presented SPF and pH values statistically different (p < 0.05) between temperatures. CONCLUSION: The formulation SSPFCX4CA4 presented SPF values >6, so they present potential for photoprotective or multifunctional products.


Assuntos
Etanol/química , Myrtaceae/química , Extratos Vegetais/química , Protetores Solares/química , Composição de Medicamentos , Myrtaceae/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Fator de Proteção Solar , Raios Ultravioleta
15.
Pharm Res ; 36(8): 120, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31214939

RESUMO

PURPOSE: The first pressurised metered dose inhaler (pMDI) was introduced in 1956. Even with excellent inhaler technique typically only 20% of the dose deposits in the lungs where needed. It is hoped that a better understanding of the initial plume formation and expansion during dose release can help improve modelling, devices and ultimately transport to the lungs. We have used two high-speed imaging techniques to investigate the transient dose event. METHODS: Synchrotron phase-contrast X-Ray imaging is a technique that is sensitive to variations in the refractive index of materials in the X-ray region. Similarly, Schlieren imaging is an optical technique sensitive to the refractive index gradients which are often present in pMDI plumes due to gas density variations. We have combined and synchronised both techniques to investigate three commercial pMDIs actuators during dose release for various actuator/formulation combinations. RESULTS: We have observed temporal phases of propellant flowing in the orifice channel. At early times flash boiling takes place and drives gas emission, steep plume density gradients and liquid jets/droplets at the orifice. Evaporating liquid is present in the sump long after the dose is finished. Regional counter-flow is seen in plumes emitted into a mouth-throat geometry. CONCLUSIONS: As the foamy liquid-vapour mixture is forced out of the sump and into the orifice the liquid walls of the bubbles break into fragments which are forced out of the sump and tend to form a liquid-gas flow in the orifice channel. The period of high density plume observed by the schlieren technique corresponds to flash-boiling-driven liquid exiting the orifice channel.


Assuntos
Inaladores Dosimetrados , Administração por Inalação , Aerossóis , Composição de Medicamentos/métodos , Desenho de Equipamento/instrumentação , Etanol/química , Humanos , Cinética , Boca , Imagem Óptica/métodos , Faringe , Raios X
16.
Ultrason Sonochem ; 57: 89-97, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31208622

RESUMO

This paper presents the successful application of ultrasound-assisted packed-bed (UAE-PB) method for the extraction of hypericin from the Hypericum perfuratum L. The Soxhlet system was utilized for the determination of suitable solvent from ethanol, methanol or from the mixture of different proportions of ethanol-methanol. The mixture of 50:50 v/v ethanol-methanol was obtained to be the most suitable solvent since it led to the highest extraction amount of hypericin. The extraction amount of hypericin increased by 13.6% and 21.4% when the solvent changed from pure methanol to the mixture of 50:50 v/v ethanol-methanol for the extraction time of 3 and 8 h, respectively. Subsequently, the extraction was conducted through the UAE-PB, and the effects of temperature, time, and the ratio of solvent to the dried plant were studied. The response surface method (RSM) was used to investigate the effect of parameters on the extraction in the UAE-PB system. At the temperature of 60 °C, extraction time of 105 min, and the solvent to plant ratio of 15.3, the maximum extraction yield of hypericin was achieved. In the optimal conditions, the amount of extraction was 0.112 mg hypericin/g dried plant, which was in accordance with the optimized predicted value (0.111 mg hypericin/g dried plant) from Design-Expert software.


Assuntos
Hypericum/química , Perileno/análogos & derivados , Ondas Ultrassônicas , Cromatografia Líquida de Alta Pressão/métodos , Etanol/química , Metanol/química , Modelos Químicos , Perileno/análise , Reprodutibilidade dos Testes , Solventes/química , Temperatura Ambiente , Fatores de Tempo
17.
Pharm Res ; 36(7): 100, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089892

RESUMO

PURPOSE: Evaporation and particle formation from multi-solvent microdroplets containing solid excipients pertaining to spray-drying of therapeutic agents intended for lung delivery were studied. Various water and ethanol co-solvent systems containing a variety of actives and excipients (beclomethasone, budesonide, leucine, and trehalose) were considered. METHODS: Numerical methods were used to predict the droplet evaporation rates and internal solute transfers, and their results verified and compared with results from two separate experimental setups. In particular, an electrodynamic balance was used to measure the evaporation rates of multicomponent droplets and a monodisperse droplet chain setup collected dried microparticles for further analytical investigations and ultramicroscopy. RESULTS: The numerical results are used to explain the different particle morphologies dried from solutions at different co-solvent compositions. The obtained numerical data clearly show that the two parameters controlling the general morphology of a dried particle, namely the Péclet number and the degree of saturation, can change with time in a multi-solvent droplet. This fact complicates product development for such systems. However, this additional complexity vanishes at what we define as the iso-compositional point, which occurs when the solvent ratios and other composition-dependent properties of the droplet remain constant during evaporation, similar to the azeotrope of such systems during distillation. CONCLUSIONS: Numerical and experimental analysis of multi-solvent systems indicate that spray-drying near the iso-compositional ratio simplifies the design and process development of such systems.


Assuntos
Excipientes/química , Nebulizadores e Vaporizadores , Solventes/química , Administração por Inalação , Beclometasona/química , Budesonida/química , Dessecação , Etanol/química , Cinética , Leucina/química , Pós/química , Teoria Quântica , Trealose/química , Água/química
18.
J Food Sci ; 84(6): 1297-1307, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31116886

RESUMO

Brazil is home to a wide variety of flora, including several lesser known species, such as araçá that were processed in this study using two green technologies consecutively: supercritical fluid extraction (SFE) for nonpolar fraction and pressurized liquid extraction. For polar fraction, the experiments followed a central composite design involving ethanol as solvent, with temperature and static time in each bath as independent variables. Both extracts were analyzed for antioxidant and antimicrobial activities. Total phenolics content (TPC) was determined for all ethanol extracts. In the araçá essential oil (AEO) obtained by SFE, the extraction yield was 2.33%. The three major compounds of AEO were α-pinene (20.75%), p-cymene (20.50%), and o-cymene (20.05%). In ethanol extracts, the high yield (14.49%) was obtained at 74 °C/6 min and the major TPC (136.95 mg GAE/100 g) at 60 °C/9 min. Ethanol extracts presented good antioxidant activity (EC50 = 6.37 mg/mL) at 74 °C/6 min. AEO was unable to reduce DPPH• concentration by 50%. Both extract types presented an inhibitory effect against Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus cereus, while only the ethanol extracts presented effect against Listeria monocytogenes. This work had the aim to present the innovation of the use of a whole typical Brazilian fruit that gives rise to extracts with excellent properties for employment in both the pharmaceutical and food industries.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Cromatografia com Fluido Supercrítico/métodos , Química Verde/métodos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Psidium/química , Antibacterianos/química , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Bacillus cereus/efeitos dos fármacos , Brasil , Dióxido de Carbono/química , Cromatografia com Fluido Supercrítico/instrumentação , Etanol/química , Frutas/química , Química Verde/instrumentação , Óleos Voláteis/análise , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Fenóis/análise , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/análise , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
19.
J Opt Soc Am A Opt Image Sci Vis ; 36(5): 877-882, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31045016

RESUMO

Proper understanding of Raman spectroscopic signals from biological samples requires the quantification of internal signal absorption and its effect on the Raman spectra detected outside the samples under study. In this paper, we describe an efficient Monte Carlo method to simulate Raman scattering in biological tissues and solutions and compare the findings with experimental results obtained in samples with different absorber concentrations and optical properties. As an illustrative example, we focus on solutions of beta-carotene (bCar) in ethanol with different concentrations of absorber (ink) added. We find good agreement between simulation and experiment, thus indicating a way to quantify the influence of internal signal absorption in Raman measurements.


Assuntos
Absorção Fisico-Química , Método de Monte Carlo , Fenômenos Ópticos , Análise Espectral Raman , Etanol/química , beta Caroteno/química
20.
Carbohydr Polym ; 216: 189-196, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047056

RESUMO

In this study, the composite of carboxymethyl cellulose (CMC) film modified with gelatin and TiO2-Ag nanoparticles (CMC/Gel/TiO2-Ag) was prepared and some properties of synthesized film including physicochemical and photocatalytic properties were investigated. FT-IR results showed that new interactions between the film components were created. Scanning electron microscopy (SEM) results showed that the TiO2-Ag particles with 50-100 nm distributed in the CMC/Gelatin film. The results of the mechanical test showed that the TiO2-Ag nanoparticles at low concentrations increased tensile strength (TS) and decreased strain to break (STB), but with increasing nanoparticles concentrations, TS decreased and STB increased. Photocatalytic study showed that the prepared CMC/Gel/TiO2-Ag film has good photocatalytic property. Gas chromatography was used to study photocatalytic effects of film. Increasing TiO2-Ag nano particles on the film increases the photocatalytic activity of films against NH3, ethanol and benzene.


Assuntos
Plásticos Biodegradáveis/química , Carboximetilcelulose Sódica/química , Gelatina/química , Nanopartículas Metálicas/química , Prata/química , Titânio/química , Amônia/química , Benzeno/química , Plásticos Biodegradáveis/síntese química , Plásticos Biodegradáveis/efeitos da radiação , Carboximetilcelulose Sódica/síntese química , Carboximetilcelulose Sódica/efeitos da radiação , Catálise , Módulo de Elasticidade , Etanol/química , Gelatina/síntese química , Gelatina/efeitos da radiação , Luz , Membranas Artificiais , Nanopartículas Metálicas/efeitos da radiação , Nanocompostos/química , Nanocompostos/efeitos da radiação , Permeabilidade , Prata/efeitos da radiação , Vapor , Resistência à Tração , Titânio/efeitos da radiação , Água/química
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