abstract: The effects of chemical and physical methods on multiwalled carbon nanotube (MWCNT) dispersion in Portland cement pastes were investigated. Consistency, rheology, compressive strength, dynamic elastic modulus, flexural strength, water absorption, and void content tests were performed to evaluate these effects. Changes in the rheology of the cement pastes and surfactants resulted in a significant reduction in apparent viscosity and yield strength. Additionally, cement pastes containing carboxyl- functionalized MWCNTs (MWCNT-COOH) and surfactant showed higher compressive strengths at 28 d. However, the ultrasonic dispersion method did not significantly influence the properties of hardened Portland cement compared with Portland cement produced using the non-sonicated aqueous solution.

resumo: Foram investigados os efeitos dos métodos químicos e físicos na dispersão de nanotubos de carbono de paredes múltiplas (MWCNT) em pastas de cimento Portland. Para avaliar estes efeitos, foram realizados testes de consistência, reologia, resistência à compressão, módulo elástico dinâmico, resistência à flexão, absorção de água, e teor de vazio. As alterações na reologia das pastas de cimento e surfactantes resultaram numa redução significativa da viscosidade aparente e da resistência ao escoamento. Além disso, pastas de cimento contendo MWCNT funcionalizados com grupo carboxílicos (MWCNT-COOH) e surfactante mostraram maiores resistências à compressão a 28 d. No entanto, o método de dispersão ultrassônica não influenciou significativamente as propriedades do cimento Portland endurecido em comparação com o cimento Portland produzido utilizando a solução aquosa não sonicada.

The aim of this study was to analyze the physicochemical properties and antifungal activities of the red propolis samples from Sergipe, Brazil, and also evaluate their variability throughout the year. The characterization of the hydroalcoholic extract (HPE) of the red propolis samples was performed monthly from October 2009 to September 2010. The concentrations of the bioactive compounds varied during the year, but their chromatographic profiles were similar. Four compounds were identified by comparison with authentic standards. Formononetin was one of the predominant compounds in all propolis extracts. In our study, it was observed that all the propolis samples inhibited the growth of Candida species. Multivariate analysis confirmed the variations in chemical composition and color of the HPEs throughout the year. The biological activities of the HPEs were statistically significant (p<0.05), and all samples exhibited antifungal properties.

O trabalho teve como objetivo desenvolver e caracterizar embalagens ativas flexíveis formuladas pela incorporação de polpas de frutas tropicais a uma matriz polimérica de amido de mandioca plastificada com glicerol, avaliando as propriedades mecânicas, de barreira e a eficácia antioxidante destas embalagens durante o armazenamento. As embalagens foram produzidas por casting, com concentrações fixas de amido de mandioca (4,5%) e glicerol (1,0%), e concentrações de polpa de manga, acerola e seriguela entre 5 e 20%. Foram caracterizadas as propriedades de barreira (espessura, umidade, sólidos totais, atividade de água e solubilidade) e propriedades mecânicas dos filmes. A ação antioxidante dos aditivos incorporados foi avaliada através do armazenamento do azeite de dendê embalado com os filmes contendo os aditivos naturais, monitorando a sua oxidação por 40 dias, sob condições de oxidação acelerada (63%UR/30°C). A adição das polpas de frutas aos filmes promoveu um aumento da resistência mecânica. Os filmes com as polpas incorporadas desempenharam efeito antioxidante sobre o azeite de dendê durante os 40 dias de armazenamento, podendo ser aplicados para o controle da oxidação deste produto.

This research aimed to develop and characterize flexible active packages formulated by the incorporation of pulps from tropical fruits to a polymeric matrix of manioc starch, plasticized with glycerol. The mechanical properties, the barriers and the antioxidant efficacy of these packages were evaluated during storing. The packages were produced by casting, with fixed concentrations of manioc starch (4.5%) and glycerol (1.0%), and variable concentrations of mango, acerola and seriguela pulps between 5 and 20%. The barrier properties (width, humidity, total solids, water activity and solubility) and the mechanical properties of the films were evaluated. The antioxidant action of the additives incorporated was evaluated through the storage of palm oil packed with the films containing the natural additives. Its oxidation was monitored for 40 days, under conditions of accelerated oxidation (63%UR/30ºC). The addition of fruit pulps to the films promoted an increase of the mechanical resistance. The films with the added pulps performed an antioxidant effect on the palm oil during the 40 days storage, which could be applied for the oxidation control of this product.

Um destino para resíduos agro-industriais é usá-los como substratos fermentescíveis, diminuindo o custo na produção de produtos com alto valor agregado. Este trabalho avaliou a influência da natureza dos resíduos fermentescíveis e das cepas de Xanthomonas sobre a produção e propriedades do biopolímero resultante. A produção foi realizada em agitador orbital (250 rpm / 28 °C / 120 h) por fermentação de sacarose (controle), glicerina residual do biodiesel e resíduo líquido de sisal. Tanto a composição do substrato como as cepas mostraram um forte efeito sobre a produção (0,36-2,40 gL- 1), viscosidade aparente (13,73 para 36,31 mPa.s) e massa molecular (2,1-5,9 × 10(6) Da) da goma de xantana resultante, não influenciando o comportamento pseudoplástico de soluções aquosas dos biopolímeros.

A destination for agro-industrial waste is to use them as fermentation substrates. This work was aimed at evaluating the influence of the nature of the waste fermented by two strains of Xanthomonason on the biopolymer properties. The production was performed in an orbital shaker (250 rpm / 28 °C / 120 h) by fermentation of sucrose (control), crude glycerin from biodiesel and sisal liquid waste. Both the fermented substrate composition and the strains had a strong impact on production (0.36 to 2.40 g.L- 1), apparent viscosity (13.73 to 36.31 mPa.s) and molecular mass (2.1 to 5.9 × 10(6) Da) of the resulting xanthan gum, but they did not affect the pseudoplastic behavior of aqueous biopolymers solutions.

PURPOSE: To evaluate the effects of fatty acids-incorporated collagen-based dressing films on wound healing in rodents. METHODS: Therefore, surgical wounds were performed in the back of 80 Wistar rats, and dressed with collgane-based films (COL), and collagen-based films containing fatty acids (AGEF50 and AGEF100). Undressed wounds were regarded as controls (CTR). The animals were euthanized after three, seven, 14 and 21 days, and the macroscopic wound contraction rates (WRC) were assessed. The wounded area was also analyzed by conventional and polarized light microscope. RESULTS: No sign of abscess or hypertrophic scar formation was observed in none of the groups. At seven days, the WRR of AGEF50 was significantly higher than CTR (p<0.01), whereas at 14 days, both AGE 50 and AGE100 showed a significant increase of the WRR compared to CTR (p<0.001) and COL (p<0.01). Both films promoted increased influx of neutrophils at three days (p<0.01), but reduced significantly the mononuclear infiltrate at 14 days (p<0.05). It was also observed earlier maturation of the granulation tissue, full epithelization and cutaneous appendages development, as well as better collagenization, in AGEF50 and AGEF100. CONCLUSION: The application of AGEF50/100 as wound dressing improved wound healing in rodents.

Estudos têm demonstrado que componentes hidrossolúveis da própolis verde, flavonóides, apresentam atividade antitumoral. FORMA DE ESTUDO: Estudo experimental. OBJETIVO: Avaliar o efeito do extrato hidroalcoólico de própolis verde (EPV) sobre displasias epiteliais linguais quimicamente induzidas em ratos. MATERIAIS E MÉTODOS: Neste estudo, foi pincelado DMBA (9,10-dimetil-1,2- benzatraceno) no dorso lingual de ratos 3x/semana, em dias alternados, administrado 100 (PROP1), 200 (PROP2) e 300 mg/kg (PROP3) de EPV (v.o.), durante 20 semanas. A substituição do EPV ou DMBA pelos seus veículos foi usada nos controles positivos (TUM1 e TUM2), negativos (CTR1 e CTR2), respectivamente. O epitélio lingual foi analisado histologicamente, graduado pelo Sistema Binário e classificação OMS, e os dados comparados por análise de variância (ANOVA) (p<0,05). RESULTADOS: O rendimento do EPV foi 41,43% e o teor de flavonóides 0,95±0,44%. Segundo o Sistema Binário, TUM1, TUM2 e PROP1 foram considerados lesões de alto risco, apresentando índices de alterações morfológicas significativamente mais elevados (p<0,05), e os demais de baixo risco. Segundo a classificação OMS, observou-se displasia moderada em TUM e TUM2, leve em PROP1, PROP2 e PROP3, e ausente em CTR1 e CTR2. Conclusão: Sugere-se que o EPV possa desempenhar um papel protetor importante durante a carcinogênese lingual quimicamente induzida em ratos. CONCLUSÃO: Sugere-se que o EPV possa desempenhar um papel protetor importante durante a carcinogênese lingual quimicamente induzida em ratos.

Studies have demonstrated that flavonoid compounds of green propolis have antitumoral activity. STUDY DESIGN: Experimental study. AIMS: To evaluate the effect of a hydroalcoholic extract of green propolis (EPV) on chemically induced epithelial dysplasias in rat tongues. METHODS AND MATERIALS: DMBA was brushed on the lingual dorsum of rats 3x/week on alternate days - 100 (PROP1), 200 (PROP2) and 300 mg/kg (PROP3) EPV was administered orally for 20 weeks. EPV or DMBA were replaced by their vehicles and applied as positive (TUM1 and TUM2) and negative controls (CTR1 and CTR2), respectively. The lingual epithelium was histologically analyzed and graded according a binary system and the WHO classification; the data were compared using ANOVA (*p<0.05). RESULTS: The EPV yield was 41% and the flavonoid yield was 0.95±0.44%. According to the Binary System, TUM1, TUM2 and PROP1 were considered high risk lesions, with significantly higher morphological alteration rates compared to the other groups (p<0.05), which were considered low risk lesions. Based on the WHO classification, moderate dysplasia was TUM1 and TUM2, mild dysplasia was PROP1, PROP2 and PROP3, and non-dysplastic epithelium was CTR1 and CTR2. CONCLUSION: EPV seems to play an important protective role against chemically-induced lingual carcinogenesis in rats.

Objetivou-se obter neste trabalho um corante natural (antocianina), na forma de pó a partir do bagaço de uva da cultivar "Isabel" (Vitis labrusca), onde foram realizados estudos de extração e encapsulamento. Empregou-se o método de extração por imersão mediante técnica de planejamento experimental, onde as variáveis avaliadas foram pH da solução de extração (1-2), volume de etanol (100-250 mL), tempo de extração (3-7 h) e temperatura de extração (15-35ºC). A concentração máxima de antocianinas totais obtidas foi de 300 mg/100 g de bagaço de uva (umidade 5%) nos níveis inferiores de pH (1,0) e tempo (3 horas) e superiores de temperatura (35ºC) e volume de etanol (250 mL). Os extratos foram secos por atomização. A melhor condição para o encapsulamento e a secagem foi quando utilizaram-se proporções iguais de maltodextrina e goma arábica.

This work had the aim of obtaining a natural pigment (anthocyanin) at powder form from 'Isabel' grape bagasse (Vitis labrusca), studying the extraction and encapsulating steps one applied the method of extraction by immersion by experimental design technique, when the factors investigated were pH of the extraction solution (1-2), volume of ethanol (100-250 mL), extraction time (3-7 h) and extraction temperature (15-35 °C). The maximum concentration of total anthocyanin was 300 mg/100g of grape bagasse (5% moisture) at the lower levels of pH (1.0) and time (3 h), and at upper levels of temperature (35ºC) and amount of ethanol (250 mL). The extracts were dried by a spray process. The best condition for encapsulating and drying was obtained when equal amounts of maltodextrin and Arabic gum were used.

Com este trabalho, avaliou-se a produção de biopolímero sintetizado por Sphingomonas capsulata ATCC 14666, utilizando-se os meios industriais melaço bruto e pré-tratado e resíduo de proteína texturizada de soja (PTS). Foram testadas diferentes concentrações de meios industriais (2,66, 4, 6 e 8%), cujas condições de fermentação utilizadas foram 28º ± 2ºC, 208 rpm, 72 h. Os ensaios foram realizados em triplicata e os resultados foram avaliados estatisticamente mediante o teste de Tukey. As melhores produtividades foram obtidas para melaço pré-tratado 8% (0,290 gL-1h-1), seguida de extrato aquoso de resíduo de PTS 6% (0,240 gL-1h-1) e melaço bruto 8% (0,190 gL-1h-1). A qualidade reológica das gomas foi demonstrada através da leitura de viscosidade aparente de soluções aquosas e salinas a 25 e 60ºC.

This work studied the biopolymer production by Sphingomonas capsulata ATCC 14666 using industrial raw material and pretreated molasses and aqueous extract of textured soy protein (TSP). Different concentrations of industrial media (2.66, 4, 6 and 8 w/t%) were evaluated at 28º ± 2ºC, 208rpm, 72h, were the fermentation conditions utilized. Triplicate assays were conducted and Tukey's test was used. The highest productivity were obtained for 8% of pretreated molasses (0,290 gL-1h-1), 6% of aqueous extract of TSP (0,240 gL-1h-1) and 8% raw molasses (0,190 gL-1h-1), respectively. The rheological behavior of aqueous and saline (NaCl and CaCl2 3% wt/v) solutions of biopolymers were investigated by apparent viscosity analysis at 25 and 60ºC.