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Influence of Urea, Isopropanol, and Propylene Glycol on Rutin In Vitro Release from Cosmetic Semisolid Systems Estimated by Factorial Design

BABY, Andre Rolim; HAROUTIOUNIAN-FILHO, Carlos Alberto; SARRUF, Fernanda Daud; PINTO, Claudineia Aparecida Sales de Oliveira; KANEKO, Telma Mary; VELASCO, Maria Valeria Robles
Fonte: TAYLOR & FRANCIS INC Publicador: TAYLOR & FRANCIS INC
Tipo: Artigo de Revista Científica
ENG
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Rutin, one of the major flavonoids found in an assortment of plants, was reported to act as a sun protection factor booster with high anti-UVA defense, antioxidant, antiaging, and anticellulite, by improvement of the cutaneous microcirculation. This research work aimed at evaluating the rutin in vitro release from semisolid systems, in vertical diffusion cells, containing urea, isopropanol and propylene glycol, associated or not, according to the factorial design with two levels with center point. Urea (alone and in association with isopropanol and propylene glycol) and isopropanol (alone and in association with propylene glycol) influenced significant and negatively rutin liberation in diverse parameters: flux (g/cm2.h); apparent permeability coefficient (cm/h); rutin amount released (g/cm2); and liberation enhancement factor. In accordance with the results, the presence of propylene glycol 5.0% (wt/wt) presented statistically favorable to promote rutin release from this semisolid system with flux = 105.12 8.59 g/cm2.h; apparent permeability coefficient = 7.01 0.572 cm/h; rutin amount released = 648.80 53.01 g/cm2; and liberation enhancement factor = 1.21 0.07.; CNPq/MCT; CAPES

Factorial design to optimize microwave-assisted synthesis of FDU-1 silica with a new triblock copolymer

Silva, Luis Carlos Cides da; REIS, T. V. S. dos; COSENTINO, I. C.; Fantini, Marcia Carvalho de Abreu; MATOS, J. R.; BRUNS, R. E.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
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The synthesis of FDU-1 silica with large cage-like mesopores prepared with a new triblock copolymer Vorasurf 504 (R) (Eo)(38)(BO)(46)(EO)(38) was developed. The hydrothermal treatment temperature, the dissolution of the copolymer in ethanol, the HCl concentration, the solution stirring time and the hydrothermal treatment time in a microwave oven were evaluated with factorial design procedures. The dissolution in ethanol is important to produce a material with better porous morphology. Increases in the hydrothermal temperature (100 degrees C) and HCl concentration (2 M) improved structural, textural and chemical properties of the cubic ordered mesoporous silica. Also, longer times induced better physical and chemical property characteristics. (C) 2010 Elsevier Inc. All rights reserved.; FAPESP[03/10067-3]; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); FAPESP[2007/07646-2]; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); CNPq; CAPES; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento tecnológico de soluções extrativas aquosas de Phyllanthus niruri L. (quebra-pedra) empregando planejamento fatorial; Technological development of aqueous extracts from phyllanthus niruri l. by using of factorial design

Soares, Luiz Alberto Lira; Gonzalez Ortega, George; Bassani, Valquiria Linck; Petrovick, Pedro Ros
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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Planejamento fatorial do tipo 32 foi realizado para avaliar a influência dos parâmetros: técnica de extração (infusão/decocção); proporção planta:solvente (2,5% e 7,5 %) e tempo de extração (5 e 15 minutos), sobre o teor de flavonóides encontrado em soluções extrativas aquosas de Phyllanthus niruri L. A solução que apresentou maior teor de flavonóides teve suas características físico-químicas determinadas.; A factorial design 32 was used to evaluated the influence of extraction technique (infusion/decoction), plant: solvent ratio (2.5 % and 7.5 %), and extraction time (5 and 15 minutes) on the total flavonoids content of aqueous extractive solutions from Phyllanthus niruri L. The extractive solution that showed higher total flavonoid content had their physico-chemical characteristics determinated.

Cationic dyes immobilized on cellulose acetate surface modified with titanium dioxide : factorial design and an application as sensor for NADH

Hoffmann, Andrea Anilda; Dias, Silvio Luis Pereira; Benvenutti, Edilson Valmir; Lima, Éder Cláudio; Pavan, Flávio André; Rodrigues, Jordana Roider; Scotti, Rodrigo; Ribeiro, Emerson Schwingel; Gushikem, Yoshitaka
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
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As propriedades eletroquímicas dos corantes catiônicos, azul de meldola e azul de toluidina, imobilizados na superfície do acetato de celulose modificado com dióxido de titânio foram investigadas por voltametria cíclica. Os materiais sintetizados foram empregados como eletrodos de pasta de carbono. As propriedades mediadoras redox dos eletrodos modificados quimicamente com azul de meldola e azul de toluidina foram otimizadas utilizando um planejamento fatorial consistindo de dois níveis e quatro fatores com dois pseudo-pontos centrais (n=20 experimentos). A análise fatorial foi realizada para investigar as melhores condições de reversibilidade do processo redox tais como uma diminuição na separação entre os picos de potenciais anódico e catódico e razão de corrente próxima da unidade. Os fatores que apresentaram efeitos significantes na otimização global do sistema e que permitiram alcançar as melhores condições de reversibilidade de transferência de elétrons foram os fatores principais velocidade de varredura e tipo de eletrodo (azul de meldola ou azul de toluidina) além dos fatores de interação concentração do KCl × tipo de eletrodo (B×D) e a interação pH × [KCl] × velocidade de varredura (A×B×C). As melhores condições de reversibilidade eletroquímica obtidas foram: o eletrodo CA-TiO2-MB...

Azul de metileno imobilizado na celulose/TiO2 e SiO2/TiO2 : propriedades eletroquímica e planejamento fatorial; Methylene blue immobilized in cellulose/tio2 and sio2/tio2 : electrochemical properties and factorial design

Scotti, Rodrigo; Lima, Éder Cláudio; Benvenutti, Edilson Valmir; Piatnicki, Clarisse Maria Sartori; Dias, Silvio Luis Pereira; Gushikem, Yoshitaka; Kubota, Lauro Tatsuo
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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The electrochemical properties of methylene blue immobilized on cellulose/TiO2 and mixed oxide SiO2/TiO2 matrices were investigated by means of cyclic voltammetry. The electron mediator property of the methylene blue was optimized using a factorial design, consisting of four factors in two levels. The experimental observations and data analyses on the system indicate that the lowest peak separation occurs for Sil/TiOAM, 1.0 mol L-1 KCl solution and 20 mV s-1 scan rate, while values of current ratio closest to unity were found for Cel/TiOAM independent of electrolyte concentration, 0.2 or 1.0 mol L-1, and scan rate, 20 mV s-1 or 60 mV s-1.

Ethanol production by Zymomonas mobilis during sucrose fermentation: Optimization of culture conditions using factorial design

Ernandes, Fernanda Maria Pagane Guereschi; Garcia-Cruz, Crispin Humberto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 78-78
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Current interest in ethanol as a potential fuel has stimulated research on various aspects of the fermentation process. Different techniques for increasing productivity, such as continuous culture, cell recycle amd vacuum distillation, have been evaluted, but another important consideration is the improvement of the fermenting organism to give maximum productivity. One of the most promising ethanol-producing organisms is the bacterium Zymomonas mobilis. Zymomonas mobilis is a unique bacteria among the microbial world, with peculiar growth, energy production and responde to culture conditions, causing a great interest in scientific, biotechnological and industrial fields. The bacteria`s ability to make possible energy production in favor of product formation, respond to physical and chemical environmental manipulation as well as its limited product formation make it an ideal microorganism for the study and development of microbial processes for ethanol production. The aim of this work was analyse the optimum operational conditions for the ethanol production by Zymomonas mobilis CCT 4494. Inoculum was prepared from activated culture using Erlenmeyer flasks containing 50 mL of fermentation medium. The flasks were placed on orbital shaker (model MA 830) under controlled temperature (30°C)...

Application of factorial design for the ab initio study of cis- and trans-1,2 dihaloethylene stabilities

Silva,João Bosco P. da
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2000 EN
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The chemometric technique Two Level Factorial Design was used to evaluate the principal and interaction effects of wave function modifications on calculated energy differences (DE) between the cis and trans isomers of 1,2-dihaloethylenes, C2H2X2 (X=F and Cl). The factorial profile of DE is quite different for these systems. The addition of polarization and diffuse functions to the basis set have the largest effects in describing cis 1,2-difluoroethylene as the most stable isomer. In contrast electronic correlation, at the MP2 level, and the inclusion of polarization functions in the basis set have the largest effects in describing the cis form as the most stable one in the 1,2-dichloroethylenes. In both systems the interaction effects are smaller than the principal effects.

Use of factorial design for optimization of microwave-assisted digestion of lubricating oil

Costa,Letícia M.; Ferreira,Sérgio L. C.; Nogueira,Ana Rita A.; Nóbrega,Joaquim A.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2005 EN
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This work proposes the use of factorial design for optimization of microwave-assisted digestion of lubricating oil. The accuracy of digestion procedures is affected by critical experimental parameters, such as sample amount, concentrated acid volumes, microwave radiation applied power, and digestion time. The effects of these key variables on the microwave-assisted digestion efficiency were investigated. The residual carbon content and the acidity were determined in all digestates after microwave-assisted digestion as response of the factorial design. Calcium, Cu, Mg, P, S, and Zn were determined in oil digestates obtained by using two systems: a cavity- and a focused-oven. The accuracy was checked using one standard reference material, NIST SRM 1848 - Lubricating Oil Additive Package. All determined and certified values are in agreement at a 95% confidence level. The digestion time, microwave applied power, sample mass, and the interaction between these variables were significant according to P-values when the analysis of variance (ANOVA) was used.

Cationic dyes immobilized on cellulose acetate surface modified with titanium dioxide: factorial design and an application as sensor for NADH

Hoffmann,Andrea A.; Dias,Silvio L. P.; Benvenutti,Edilson V.; Lima,Eder C.; Pavan,Flávio A.; Rodrigues,Jordana R.; Scotti,Rodrigo; Ribeiro,Emerson S.; Gushikem,Yoshitaka
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2007 EN
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The electrochemical properties of meldola blue and toluidine blue cationic dyes immobilized on cellulose acetate surface modified with titanium dioxide were investigated by cyclic voltammetry. The materials synthesized were employed as carbon paste electrodes. The redox mediator properties of the meldola blue and toluidine blue chemically modified electrodes were optimized using a factorial design, consisting of two levels and four factors with two pseudo-central points (n= 20 experiments). The factorial analysis was carried out by searching for better reversibility of the redox process, such as the lowest separation between anodic and cathodic potential peaks and a current ratio near unity. The factors that presented significant effects on the overall optimization of the system to achieve the best conditions of the reversibility of electron transfer were the main factors scan rate and type of electrode (meldola blue or toluidine blue), besides the interaction factors KCl concentration × type of electrode (B×D) and the pH × [KCl] concentration × scan rate (A×B×C) interaction. The best electrochemical reversibility conditions obtained were: using the CA-TiO2-MB electrode, 1.0 mol L-1 KCl as supporting electrolyte...

HPLC/DAD determination of rosmarinic acid in Salvia officinalis: sample preparation optimization by factorial design

Oliveira,Karina B. de; Oliveira,Brás H. de
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
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Sage (Salvia officinalis) contains high amounts of the biologically active rosmarinic acid (RA) and other polyphenolic compounds. RA is easily oxidized, and may undergo degradation during sample preparation for analysis. The objective of this work was to develop and validate an analytical procedure for determination of RA in sage, using factorial design of experiments for optimizing sample preparation. The statistically significant variables for improving RA extraction yield were determined initially and then used in the optimization step, using central composite design (CCD). The analytical method was then fully validated, and used for the analysis of commercial samples of sage. The optimized procedure involved extraction with aqueous methanol (40%) containing an antioxidant mixture (ascorbic acid and ethylenediaminetetraacetic acid (EDTA)), with sonication at 45 ºC for 20 min. The samples were then injected in a system containing a C18 column, using methanol (A) and 0.1% phosphoric acid in water (B) in step gradient mode (45A:55B, 0-5 min; 80A:20B, 5-10 min) with flow rate of 1.0 mL min-1 and detection at 330 nm. Using this conditions, RA concentrations were 50% higher when compared to extractions without antioxidants (98.94 ± 1.07% recovery). Auto-oxidation of RA during sample extraction was prevented by the use of antioxidants resulting in more reliable analytical results. The method was then used for the analysis of commercial samples of sage.

Statistical optimization of dithranol-loaded solid lipid nanoparticles using factorial design

Gambhire,Makarand Suresh; Bhalekar,Mangesh Ramesh; Gambhire,Vaishali Makarand
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2011 EN
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This study describes a 3² full factorial experimental design to optimize the formulation of dithranol (DTH) loaded solid lipid nanoparticles (SLN) by the pre-emulsion ultrasonication method. The variables drug: lipid ratio and sonication time were studied at three levels and arranged in a 3² factorial design to study the influence on the response variables particle size and % entrapment efficiency (%EE). From the statistical analysis of data polynomial equations were generated. The particle size and %EE for the 9 batches (R1 to R9) showed a wide variation of 219-348 nm and 51.33- 71.80 %, respectively. The physical characteristics of DTH-loaded SLN were evaluated using a particle size analyzer, differential scanning calorimetry and X-ray diffraction. The results of the optimized formulation showed an average particle size of 219 nm and entrapment efficiency of 69.88 %. Ex-vivo drug penetration using rat skin showed about a 2-fold increase in localization of DTH in skin as compared to the marketed preparation of DTH.

Development and physical evaluation of Maytenus ilicifolia effervescent granules using factorial design

Cunha-Filho,Marcilio Sérgio Soares da; Gustmann,Pricila Castilho; Garcia,Felipe Sanches; Lima,Eliana Martins; Sá-Barreto,Lívia Cristina Lira de
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
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The medicinal plant Maytenus ilicifolia is a commonly used phytomedicine for the treatment of gastritis. The high dose required and low density of these extracts make necessary a daily intake of several capsules, hindering adherence to the medication. The purpose of this work was to develop a suitable dosage form for the administration of Maytenus ilicifolia using effervescent granules. A 23 factorial design was used to study the physical characteristics of the granules (particle size distribution, repose angle, Carr index, scanning electron microscopy and disintegration time). Moisture stability was also determined. According to the experimental design, granule size is the most important factor in determining the flow characteristics of effervescent granules. In turn, the disintegration time is controlled by the content of sodium bicarbonate present in the effervescent mixture as well as the granule size. The stability of formulations when exposed to moisture is strongly influenced by the percentage of effervescent mixture present in the vegetal granules. Precautions in handling and storage should be taken to ensure the stability of these preparations. The effervescent granules produced from Maytenus ilicifolia met the pharmacopoeial quality parameters...

Optimization of inulinase production by kluyveromyces marxianus using factorial design

Kalil, Susana Juliano; Suzan, Rodrigo; Maugeri Filho, Francisco; Rodrigues, Maria Isabel
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
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Factorial design and response surface techniques were used to optimize the culture medium for the production of inulinase by Kluyveromyces marxianus. Sucrose was used as the carbon source instead of inulin. Initially, a fractional factorial design (25–1) was used in order to determine the most relevant variables for enzyme production. Five parameters were studied (sucrose, peptone, yeast extract, pH, and K2HPO4), and all were shown to be significant. Sucrose concentration and pH had negative effects on inulinase production, whereas peptone, yeast extract, and K2HPO4 had positive ones. The pH was shown to be the most significant variable and should be preferentially maintained at 3.5. According to the results from the first factorial design, sucrose, peptone, and yeast extract concentrations were selected to be utilized in a full factorial design. The optimum conditions for a higher enzymatic activity were then determined: 14 g/L of sucrose, 10 g/L of yeast extract, 20 g/L of peptone, 1 g/L of K2HPO4. The enzymatic activity in the culture conditions was 127 U/mL, about six times higher than before the optimization.

Development of standardized extractive solution from Lippia sidoides by factorial design and their redox active profile

Lima,Bruno S.; Ramos,Cledison S.; Santos,João P.A.; Rabelo,Thallita K.; Serafini,Mairim R.; Souza,Carlos A.S.; Soares,Luiz A.L.; Quintans Júnior,Lucindo J.; Moreira,José C.F.; Gelain,Daniel P.; Araújo,Adriano A.S.; Silva,Francilene A.
Fonte: Sociedade Brasileira de Farmacognosia Publicador: Sociedade Brasileira de Farmacognosia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2015 EN
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AbstractThe aim of this study was to evaluate the influences of variables of preparation on total flavonoids content from extractive solution of Lippia sidoides Cham., Verbenaceae. Thus a 23 factorial design was used to study the importance of plant proportion, the extraction method and solvent on the extraction of flavonoid. The methodology of determination of chemicals in factorial design was validated according to the parameters required by Brazilian Health Agency. The extraction solution was selected through a full factorial design where the best conditions to achieve the highest content of flavonoids were: 7.5% (w/v) of plant with ethanol 50% (v/v) as solvent. The polyphenols content was determined by LC method and its relationship with the antioxidant and free radical scavenging activities was evaluated. The free radical scavenging activities and antioxidant potentials were determined for different concentrations using various in vitro models. Our results indicate that extracts exhibited a significant dose-dependent antioxidant effect as evaluated by TRAP/TAR assays. Besides, we observed an antioxidant activity against hydroxyl radicals and nitric oxide, and protection against lipid peroxidation in vitro. Our results suggest that the extract presents significant in vitro antioxidant potential indicating promising perspectives for its use as pharmaceutical/or food additive.

Development of Cationic Solid Lipid Nanoparticles with Factorial Design-Based Studies for Topical Administration of Doxorubicin

Taveira, Stephania F.; de Campos Araujo, Luciana M. P.; de Santana, Danielle C. A. S.; Nomizo, Auro; de Freitas, Luiz Alexandre P.; Lopez, Renata F. V.
Fonte: AMER SCIENTIFIC PUBLISHERS; VALENCIA Publicador: AMER SCIENTIFIC PUBLISHERS; VALENCIA
Tipo: Artigo de Revista Científica
ENG
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Topical chemotherapy using doxorubicin, a powerful anticancer drug, can be used as an alternative with reduced systemic toxicity when treating skin cancer. The aim of the present work was to use factorial design-based studies to develop cationic solid lipid nanoparticles containing doxorubicin; further investigations into the influence of these particles on the drug's cytotoxicity and cellular uptake in B16F10 murine melanoma cells were performed. A 3(2) full factorial design was applied for two different lipid phases; one phase used stearic acid and the other used a 1:2 mixture of stearic acid and glyceryl behenate. The two factors investigated included the ratio between the lipid and the water phase and the ratio between the surfactant (poloxamer) and the co-surfactant (cetylpyridinium chloride). It was observed that the studied factors did not affect the mean diameter or the polydispersity of the obtained nanoparticles; however, they did significantly affect the zeta potential values. Optimised formulations with particle sizes ranging from 251 to 306 nm and positive zeta potentials were selected for doxorubicin incorporation. High entrapment efficiencies were achieved (97%) in formulations with higher amounts of stearic acid, suggesting that cationic charges on doxorubicin molecules may interact with the negative charges in stearic acid. Melanoma culture cell experiments showed that cationic solid lipid nanoparticles without drug were not cytotoxic to melanoma cells. The encapsulation of doxorubicin significantly increased cytotoxicity...

Factorial design and characterization studies for articaine hydrochloride loaded alginate/chitosan nanoparticles

Melo, Nathalie Ferreira Silva; Campos, Estefânia Vangelie Ramos; Paula, Eneida de; Rosa, André Henrique; Fraceto, Leonardo Fernandes
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 146-152
ENG
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Nowadays, articaine hydrochloride (ATC) is a local anesthetic widely used in dental procedures, but its side effects include paresthesia and nerve injury. Alginate/chitosan nanoparticles (AG/CSnano) can be used as carrier for drugs, overcoming the problems. The aim of this work was to evaluate the factors (Calcium/alginate [Ca2+:AG] and Chitosan/alginate [CS:AG] mass ratios) influence on the average size, polydispersity index, zeta potential and encapsulation efficiency of ATC. AG/CSnano containing ATC were prepared by ionic pregelation method. A three-level factorial design was carried out and the factors varied were Ca2+/AG mass ratio and CS/AG mass ratio. There were obtained nanoparticles with size range of 340–550 nm and polydispersity index between 0.2 and 0.5, zeta potential range –19 and –22 mV and encapsulation efficiency of ATC in AG/Csnano between 22 and 45%. According to the results, the average size, polydispersity index and encapsulation efficiency were significantly affected to the variation of Ca2+/AG and CS/AG mass ratio, but the zeta potential didn't change significantly with factor variations. The factorial design showed it was possible to identify formulations that presented better results for the parameters measured. The factor chosen for the suitable formulations was the encapsulation efficiency. Through this parameter...

Evaluation of biomass production, carotenoid level and antioxidant capacity produced by Thermus filiformis using fractional factorial design

Mandelli,Fernanda; Yamashita,Fábio; Pereira,José L.; Mercadante,Adriana Z.
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2012 EN
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A fractional factorial design 2(5-1) was used to evaluate the effect of temperature, pH, and concentrations of yeast extract, tryptone and Nitsch's trace elements on the biomass, total carotenoids and protection against singlet oxygen by carotenoid extracts of the bacterium Thermus filiformis. In addition, the carotenoid composition was determined by high-performance liquid chromatography connected to a diode array and mass spectrometer detectors (HPLC-DAD-MS/MS). The production of biomass ranged from 0.113 to 0.658 g/L, the total carotenoid from 137.6 to 1,517.4 mg/g and the protection against singlet oxygen from 4.3 to 85.1 %. Results of the fractional factorial design showed that temperature had a negative effect on biomass production and a positive effect on carotenoid content and protection against singlet oxygen, besides, high levels of pH value, concentrations of yeast extract and tryptone had a positive effect on biomass production only at lower temperatures. The main carotenoids of T. filiformis were thermozeaxanthins. In the tested conditions, changes in the levels of the variables influenced the biomass, carotenoid production, and protection against singlet oxygen, although they did not influence the carotenoid profile. The results of this study provide a better understanding on the interactions among certain nutritional and cultivation conditions of a thermophile bacterium...

Optimization of nano-emulsions prepared by low-energy emulsification methods at constant temperature using a factorial design study

Pey, C. M.; Maestro, Alicia; Solé, Isabel; González Azón, Carmen; Solans, Conxita; Gutiérrez, José M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 19968 bytes; application/msword
ENG
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7 pages, 6 figures, 5 tables.-- Printed version published Oct 5, 2006.-- Issue title: Papers from "Formula IV: Frontiers in Formulation Science", an International conference organised by the RSC, held in London, July 4-7th 2005.; The aim of this work is the study and optimization of composition and preparation method of nano-emulsions O/W by addition of one of the components at constant temperature. Experimental design techniques have been used to carry out this study. A factorial design has been done in order to investigate the effect of formulation and preparation variables over emulsion properties. The conclusion of this study is that emulsion droplet size and polydispersity change with composition and preparation method. These variables have been optimized using a central composite design obtaining response surfaces that describe this preparation method of nano-emulsions.; This work was funded under Spanish MCYT Project No. PPQ2002-04514-C03-02.; Peer reviewed

Statistical optimization of dithranol-loaded solid lipid nanoparticles using factorial design

Gambhire, Makarand Suresh; Bhalekar, Mangesh Ramesh; Gambhire, Vaishali Makarand
Fonte: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/09/2011 ENG
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Este estudo descreve o planejamento factorial 3² para otimizar a formulação de nanopartículas lipídicas sólidas (SLN) carregadas com ditranol (DTH) pelo método da ultrassonificação pré-emulsão. As variáveis como proporção de fármaco:lipídio e o tempo de sonicação foram estudados em três níveis e arranjados em planejamento fatorial 3² para estudar a influência nas variáveis de resposta tamanho de partícula e eficiência percentual de retenção do fármaco (%EE). Pela análise estatística, geraram-se equações polinomiais. O tamanho da partícula e a %EE para os 9 lotes (R1 a R9) mostraram ampla variação, respectivamente, 219-348 nm e 51,33-71,80%. As características físicas das SLN carregadas com DTN foram avaliadas utilizando-se analisador de tamanho de partícula, calorimetria de varredura diferencial e difração de raios X. Os resultados da formulação otimizada mostraram tamanho médio de partícula de 219 nm e eficiência de retenção do fármaco de 69,88%. A penetração ex vivo do fármaco utilizando pele de rato mostrou aumento de, aproximadamente, duas vezes na localização de DTH na pele, comparativamente à preparação de DTH comercializada.; This study describes a 3² full factorial experimental design to optimize the formulation of dithranol (DTH) loaded solid lipid nanoparticles (SLN) by the pre-emulsion ultrasonication method. The variables drug: lipid ratio and sonication time were studied at three levels and arranged in a 3² factorial design to study the influence on the response variables particle size and % entrapment efficiency (%EE). From the statistical analysis of data polynomial equations were generated. The particle size and %EE for the 9 batches (R1 to R9) showed a wide variation of 219-348 nm and 51.33- 71.80 %...

Evaluation of extraction conditions of 4-nerolidylchatecol from Pothomorphe umbellata (L). Miq. using factorial design; Avaliação por análise fatorial das condições da extração do 4-nerolidilcatecol de Pothomorphe umbellata (L). Miq.

Noriega, Peky; Röpke, Cristina Dislich; Camilo, César Moisés; Freitas, Paulo Chanel Deodato de; Barros, Silvia Berlanga de Moraes
Fonte: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 01/06/2005 POR
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The influence of factors: (1) time, 10 and 40 minutes, (2) particle size, 840 and 420 mm; (3) hydromodule, 1:50 and 1:100, and (4) temperature, 40 and 60 °C, in the extraction of 4-nerolidylcathecol (4-NC) from the roots of P. umbellata using factorial design "2(4)" was studied in two levels (maximal and minimal). The extraction method was maceration and the measurement of 4-NC was by HPLC with electrochemical detection. The results of the factorial analysis indicated that the main factor that increases the extraction of the active principle is particle size [effect (2): 12.2086]. The reduction of the particle size (mesh 60) increases threefold the amount of 4-nerolidylchatecol in the extract, while the time of maceration [effect (1): -0.64198], hydromodule [effect (3): 1.069804] and temperature [effect (4): -0.64198] practically do not influence the extraction. Interaction between two factors (2:3) size-hydromodule 1.181142, (2:1) size-time 0.9435065 and (2:4) size-temperature 0.0817575, showed that although the main factor size (2) increases the efficiency of the process, when one of the other three factors was taken together the amount of 4-NC extracted was not significantly increased. The technique of optimization using factorial analysis to investigate the extraction of 4-nerolylilchatecol showed to be useful to notice the interactions between factors and not only the effect of each isolated factor.; Foi avaliada a influência dos fatores (1) tempo: 10 e 40 minutos; (2) tamanho de partícula: 840 e 420 mm; (3) hidromódulo: 1:50 e 1:100 e (4) temperatura: 40 e 60 °C na extração do 4-nerolidilcatecol...