ABSTRACT Awareness about environmental problems has generated interest in the research for new materials in line with the sustainability principles. The recycling of industrial solid waste has contributed to the transformation of environmental liabilities into new products with added commercial value. In this study, the physical, me-chanical and thermal properties of low-density polyethylene (LDPE) composites reinforced with polyeth-ylene terephthalate (PET)-coated solid bleached sulfate (SBS) paperboard shavings were investigated ac-cording to composite formation process variables: preparation temperature, mean particle diameter of com-ponents and reinforcement concentration. Very few studies on the characterization of composites reinforced with PET-coated SBS paperboard shavings have been reported to date. The analyses were carried out based on standard methods published by the American Society for Testing and Materials. The results indicate an increase in the moisture content and water absorption occurred as a function of the increase in the rein-forcement. With regard to the density, there was no significant influence of variations in the granulometry or concentration of the PET-coated SBS paperboard shavings. Composites formed with particles of 0.73 mm at 140 ºC presented satisfactory tensile and flexural strength, compared with the values for the LDPE resin. Composites with 20% reinforcement formed by particles of 4.05 mm at 140 ºC showed 14% improvement in impact resistance properties. The thermal analysis indicated that shavings degradation occurred at 190 °C. Thus lower temperatures need to be applied in the processing of this composite material. The processing conditions of the composites resulted in different performance for each evaluated property. The use of the composite in manufacturing products must follow the process conditions that will provide to material the desirable level of properties for the best performance of the final product.

ABSTRACT Awareness about environmental problems has generated interest in the research for new materials in line with the sustainability principles. The recycling of industrial solid waste has contributed to the transformation of environmental liabilities into new products with added commercial value. In this study, the physical, mechanical and thermal properties of low-density polyethylene (LDPE) composites reinforced with polyethylene terephthalate (PET)-coated solid bleached sulfate (SBS) paperboard shavings were investigated according to composite formation process variables: preparation temperature, mean particle diameter of components and reinforcement concentration. Very few studies on the characterization of composites reinforced with PET-coated SBS paperboard shavings have been reported to date. The analyses were carried out based on standard methods published by the American Society for Testing and Materials. The results indicate an increase in the moisture content and water absorption occurred as a function of the increase in the reinforcement. With regard to the density, there was no significant influence of variations in the granulometry or concentration of the PET-coated SBS paperboard shavings. Composites formed with particles of 0.73 mm at 140 ºC presented satisfactory tensile and flexural strength, compared with the values for the LDPE resin. Composites with 20% reinforcement formed by particles of 4.05 mm at 140 ºC showed 14% improvement in impact resistance properties. The thermal analysis indicated that shavings degradation occurred at 190 °C. Thus lower temperatures need to be applied in the processing of this composite material. The processing conditions of the composites resulted in different performance for each evaluated property. The use of the composite in manufacturing products must follow the process conditions that will provide to material the desirable level of properties for the best performance of the final product.

RESUMO A importância do desenvolvimento de alimentos com propriedades funcionais provenientes de cogumelos comestíveis vem crescendo, surgindo assim diversas pesquisas para evolução desse mercado. No entanto é necessário a aplicação de procedimentos de conservação, pois se trata de um produto com elevado teor de umidade. O objetivo dessa pesquisa foi estudar a cinética de secagem do cogumelo shiitake (Lentinula edodes) por meio da construção de curvas de secagem, ajuste de modelos matemáticos à estas curvas e correlacionar os dados obtidos com o teor em β-glucanas para observar a influência da temperatura neste teor. Foram testadas as temperaturas de 35, 45 e 55 °C a partir de dados empíricos, construindo, assim, as curvas de secagem e quantificando o teor de β-glucanas das amostras. Posteriormente, foi realizada a aplicação de modelos matemáticos encontrados na literatura, identificando aquele que melhor represente a perda de umidade do produto durante o período de secagem. As umidades de equilíbrio resultaram em 0,346% para 35 ºC, 0,892% para 45 ºC e 0,875 para 55 ºC e os teores de β-glucanas não apresentaram diferença significativa entre as três temperaturas estudadas, confirmadas a partir do teste de Tukey. Entre os oito modelos matemáticos ajustados aos dados experimentais, os modelos de Page e Midilli apresentaram os melhores resultados. Portanto, pode-se recomendar como temperatura de secagem de Shiitake 55 °C nas condições estudadas, visto que esta resulta em menor tempo de secagem e mantêm o teor de β-glucanas.

ABSTRACT The importance of the functional properties of edible mushrooms as a food product has been increasing and several studies have emerged to address this issue. However, the application of a conservation process is required since this is a product with a high moisture level. The aim of this study was to investigate the drying kinetics of shiitake Lentinula edodes mushrooms by means of the construction of drying curves, the mathematical modeling of the drying curves, and correlating the data obtained with the β-glucan content in order to observe the influence of temperature on its content. The drying temperatures of 35 ºC, 45 ºC and 55 ºC were applied to construct the drying curves and the β-glucan contents of the samples were quantified. Mathematical modeling was performed in order to identify the best model for the representation of the product moisture loss during the drying period. The equilibrium humidity values were 0.346% for 35 ºC, 0.892% for 45 ºC and 0.875% for 55 ºC, and the β-glucan contents showed no significant difference for the three temperatures analyzed, as confirmed by the Tukey test. Of the eight mathematical models fitted to the drying curves, the Page and the Midilli models provided the best results. Therefore, based on the findings, 55 °C appears to be the optimum temperature for the Shiitake mushroom drying process in the studied conditions, as it provides the shortest drying time and the β-glucan content is maintained.

Abstract Microbial conversion for the synthesis of high added-value compounds, such as biosurfactants and lipases, is one of the most promising fields within the biotechnology industry, given its current development. In this study the simultaneous production of biosurfactants and lipases by Aspergillus niger in a submerged bioprocess was analyzed. Full Factorial Design (23) was conducted to assess the influence of the malt extract (g·L-1; 25, 50, 75) and soybean oil concentrations (% v/v; 0.0, 1.25, 2.5) and agitation rates (rpm; 0.0, 100, 200) on biosurfactant and lipase production. Higher levels of the factors favored microbial growth, while their lower levels favored the production of biosurfactants and lipases. The variables were optimized through the response surface methodology and desirability functions, obtaining simultaneous maximized values of 0.48 g·L-1 (biomass); 42.03% (EAw/o);2.17 UE (EAw/o) and 3.28 U (LA). This indicates the possibility of combined biosurfactant and lipase production.

ABSTRACT In this study, polymer composites comprised of shavings of SBS paperboard coated with polyethylene terephthalate (PET) and recycled low-density polyethylene (LDPE) were obtained. The tensile properties, flexural strength, impact resistance and water absorption were determined according to the standards published by the American Society for Testing and Materials (ASTM). The results show that the composites with the highest concentration of LDPE were more resistant to absorption when exposed to water and humidity. As regards density, a 19.5% increase of this property was verified for the 30% cellulosic fiber reinforced composite relative to the pure LDPE density. In relation to the mechanical properties, these samples were found to be very flexible in the elasticity test. The extrusion method provided adequate adhesion between the interfaces of the matrix with the fiber. The composite showed a tensile strength of approximately 55% larger than that originated by pressing. However, the values for the tensile, flexural and impact strength were lower than expected due to the lack of homogeneity of the SBS paperboard shavings.

ABSTRACT Filamentous fungi can easily degrade agro-industrial wastes in solid-state fermentation processes, synthesizing many important commercial biocompounds, such as lipolytic enzymes. The aim of this study was to evaluate the effect of the composition of the solid culture medium on the production of lipolytic enzymes by the fungus Aspergillus niger. Rice, wheat and soybean bran were mixed to prepare the culture medium, which was supplemented with glucose, glycerol or soybean oil. Four mixture experimental designs were used to find the best medium for enzyme production. According to our results, the highest lipolytic activity values were achieved with a mixture of rice bran and glycerol (19.844 U·g-1) or with rice bran only (13.267 U·g-1). Thus, the lipolytic enzyme could be produced without any additional carbon source apart from rice bran, although glycerol addition induced a higher production.

RESUMO Este estudo teve como objetivo avaliar a produção de biossurfactantes pelo fungo basidiomiceto Pleurotus sajor-caju CCB 019. A formação de biossurfactantes foi definida pela diminuição, ou seja, redução da tensão superficial (RT%) do meio de cultivo no tempo inicial e do caldo após o cultivo. Para acompanhar o crescimento micelial e a variação da tensão superficial (ΔT) do caldo de cultivo com o tempo, um biorreator de bancada (4 L) foi usado e as menores tensões superficiais ocorreram em seis dias de cultivo (144 h) (43,4 mN/m) no experimento B1 (T = 34 ° C, pH inicial de 3, agitação de 300 min-1, aeração de 0,25 L. min-1 e utilizando óleo de soja comercial) e 192 horas (8 dias) (40,7 mN/m) no ensaio B2 (as mesmas condições de B1, mas usando óleo de soja residual de fritura). O índice de emulsificação para o experimento B1, em 6 dias, foi de 66,6% e para o experimento B2, em 8 dias, foi de 65,8%. Os biosurfactantes extraídos a partir dos experimentos B1 e B2 mostraram 12,0% ± 0,5 e 10,6 ± 0,6% de carboidratos, 7,4± 0,5% e 7,7 ± 1,0% de proteína, respectivamente. Na análise do espectro de FTIR, para ambos os experimentos, podem ser identificadas bandas confirmando a presença de carboidratos e de proteínas, também sugerindo a presença de lipídeos.

ABSTRACT This study aimed to evaluate the production of biosurfactants by the fungus basidiomycete Pleurotus sajorcaju CCB 019. The biosurfactants formation was determined by the reduction of the surface tension (RT %) of the culture medium at the initial time and the culture broth at the end time. A bench top bioreactor (4 L) was used in order to monitor the mycelial growth and the ΔT in of the culture broth with time and lower surface tensions occurred six days of cultivation (144 h) (43.4 mN/m) in the experiment B1 (T=34 °C, pH Initial 3, agitation of 300 mim-1, aeration of 0.25 L.mim-1 and using commercial soybean oil) and 8 days (192 h) (40.7 mN/m) in B2 experiment (same conditions B1 but using frying residual soybean oil). The higher emulsification index for the experiment B1 in 6 days was 66.6% and for the experiment B2 at 8 days was 65.8%. The biosurfactants extracted from experiments B1 and B2 showed 12.0% ± 0.5 and 10.6 ± 0.6% carbohydrate, 7.4 ± 0.5% and 7.7 ± 1.0% of protein, respectively. In the analysis of the FTIR spectra for both the experiment can be identified bands confirming the presence of carbohydrates and proteins and suggests the presence of lipids.

Nas últimas décadas, estudos sobre nutrição humana têm enfatizado a importância da ingestão de ômega 3 e 6. Considerando que a linhaça é uma boa fonte desses ácidos graxos, neste estudo, objetivou-se desenvolver um pão de queijo enriquecido com farinha de linhaça. Foram produzidas três formulações para determinar a intensidade de alguns atributos sensoriais e para definir a melhor composição para a realização do teste de aceitação com consumidores. Na formulação selecionada, foram determinadas a taxa de expansão do pão de queijo, suas características físico-químicas, perfil de ácidos graxos e o índices de aceitação. Em relação ao sabor e às características gerais, os resultados mostraram que o pão de queijo enriquecido com farinha de linhaça foi bem aceito pelos consumidores. O produto apresentou também uma razão de ômega 6/ômega 3 de 7,32:1,0, que está dentro do recomendado. Portanto, o pão de queijo enriquecido com linhaça parece ser uma boa alternativa ao pão de queijo tradicional, especialmente no que concerne ao seu conteúdo de ômega-3 e ômega-6, que agrega benefícios nutricionais e funcionais para o produto.

In recent decades, studies on human nutrition have emphasized the importance of omega-3 and 6 intake. Since flaxseed is a good source for such fatty acids, the aim of this study was to develop a Brazilian cheese roll enriched with flaxseed flour. Three formulations were produced to determine the intensity of some sensory attributes and to set the best composition for conducting a consumer acceptance test. In the selected formulation, it was determined the Brazilian cheese roll's expansion rate, its physico-chemical characteristics, fatty acid composition and acceptance rate. Regarding its flavor and general characteristics, the results showed a good acceptance of the cheese roll enriched with flaxseed flour. The product also presented an omega-6/omega-3 ratio of 7.32:1.0, which is within the recommended one. Therefore, the cheese roll enriched with flaxseed presents as a good alternative for the traditional one, specially concerning the omega-3 and omega-6 content, which aggregates nutritional and functional benefits to the product.

The aim of this work was to study the production of compounds with antioxidant activity by Pycnoporus sanguineus when cultivated in submerged fermentation using a potato dextrose broth plus peptone medium. The study evaluated the biomass production, glucose consumption, variation of medium pH and antioxidant activity. The antioxidant potential was tested through the DPPH method and β-carotene / linoleic acid system with extracts obtained from the mycelium at different times of cultivation (5, 10, 15, 20, 25 and 30 days). Maximum kinetic values of specific growth rate (0.289 day-1), biomass productivity (0.698 g.L-1.day-1) and the yield of glucose conversion into biomass (26.24 g.g-1) were obtained during the exponential growth phase. The highest antioxidant activity was registered during the stationary phase, with a similar potential as the synthetic antioxidant BHT, in the extracts obtained at 30 days of cultivation.

Os fungos basidiomicetos do gênero Polyporus são fonte de metabólitos secundários de interesse medicinal como os compostos antibacterianos. Como estas substâncias são produzidas em pequenas quantidades pelos fungos, o estudo de condições de cultivo in vitro que otimizem sua produção, é de fundamental importância. Os efeitos da glicose e lactose, pH e agitação na concentração da biomassa e na velocidade específica de crescimento realizada pelo basidiomiceto Polyporus tricholoma foram investigados. O pH inicial (4.5, 6.5 e 8.5) foi autoregulado para pH 5.5, e a agitação aumentou o crescimento micelial e a velocidade específica de crescimento. A maior concentração das fontes de carbono (4%) incrementou a produção de biomassa. A concentração de lactose e a ausência de agitação foram determinantes na produção dos metabólitos antibacterianos. A caracterização da substância antibacteriana por CG-EM mostrou como componente majoritário o isodrimenediol, produzido pelo fungo Polyporus tricholoma, com atividade contra Staphylococcus aureus.

Basidiomycete fungi of the Polyporus genus are a source of secondary metabolites which are of medicinal interest as antibacterial compounds. As these substances are produced in a small amount by the fungi, the study of the cultivation conditions in vitro that could possibly optimize their production seems of major importance. The effects of glucose and lactose, pH and agitation on biomass concentration and on the specific growth rate caused by the basidiomycete Polyporus tricholoma were investigated. The initial pH (4.5, 6.5 and 8.5) was autoregulated at pH 5.5, and the agitation increased the mycelial growth and the specific growth rate. The high concentration of carbon sources (4%) increased biomass production. The lactose concentration and the absence of agitation were determinant in the production of antibacterial metabolites. The characterization of the antibacterial substance by GC-MS indicated a major compound, isodrimenediol, produced by the fungus Polyporus tricholoma with activity against Staphylococcus aureus.