RESUMO A planta daninha Senna obtusifolia causa severos danos em áreas de pastagens no Brasil, devido à sua elevada produção e disseminação de sementes. Objetivou-se avaliar a ação bioherbicida do caldo fermentado de Phoma dimorpha na pré-emergência e pós-emergência de S. obtusifolia. O delineamento experimental utilizado foi inteiramente casualizado, com dois tratamentos, um com e outro sem aplicação do caldo fermentado. Os efeitos bioherbicidas foram mensurados em bioensaios de pré-emergência (porcentagem de germinação), folhas destacadas (fitotoxicidade) e pós-emergência (fitotoxicidade, altura de planta e massa fresca de planta). A aplicação do caldo fermentado proporcionou ação bioherbicida em pré-emergência, inibindo em 100 % a germinação das sementes. Em folhas destacadas, ocasionou necrose e morte das folhas no nono dia após a aplicação. Na pós-emergência, essa aplicação ocasionou sintomas moderados, como manchas nas folhas e redução no tamanho da planta daninha. Conclui-se que o caldo fermentado de P. dimorpha possui ação herbicida potencial e, por isso, representa uma alternativa no desenvolvimento de bioprodutos para o controle sustentável de plantas daninhas em pastagens.

ABSTRACT The weed Senna obtusifolia causes severe damages to pasture areas in Brazil, due to its high production and seed spread. This study aimed to evaluate the bioherbicidal action of Phoma dimorpha fermented broth in the pre-emergence and post-emergence of S. obtusifolia. The experimental design was completely randomized, with two treatments, one with and other without the application of the fermented broth. The bioherbicidal effects were measured in bioassays of pre-emergence (germination percentage), detached leaves (phytotoxicity) and post-emergence (phytotoxicity, plant height and fresh plant mass). The application of the fermented broth provided a pre-emergence bioherbicidal action, inhibiting the seed germination in 100 %. In detached leaves, it caused leaf necrosis and death on the ninth day after the application. In the post-emergence, this application caused moderate symptoms, such as leaf spots and reduction in the weed plant size. It was concluded that the P. dimorpha fermented broth has a potential herbicidal action and, therefore, represents an alternative in the development of bioproducts for a sustainable weed control in pastures.

Abstract Solanum viarum Dunal belongs to the Solanaceae family and it is considered to be a grazing weed toxic to cattle. In this study, ultrasound-assisted extraction (UAE) and supercritical CO2 extraction (SFE-CO2) were applied to evaluate the extraction yield and chemical composition of fruits and roots matrices of Solanum viarum Dunal. A hydroalcoholic solution (60% ethanol/40% water, v/v) was the solvent used for UAE. For comparisons, extractions with Soxhlet and maceration were carried out. For SFE-CO2, the highest yield was obtained at 60°C and 250 bar. For UAE, the highest yield was obtained at an ultrasound intensity of 75.11 W/cm2 and pulse cycle of 0.93. The techniques seem to be efficient for the extraction of chemical compounds, indicating a large number of bioactive compounds. The major compounds are 1,2-benzenedicarboxylic acid, quinic acid, octadecenoic acid, and solasodine. The results highlight the application of UAE to recover compounds from vegetal matrices, since it presented higher yields and more chemical constituents when compared with other techniques.

Abstract Biosurfactants have many advantages over synthetic surfactants but have higher production costs. Identifying microorganisms with high production capacities for these molecules and optimizing their growth conditions can reduce cost. The present work aimed to isolate and identify a fungus with high biosurfactant production capacity, optimize its growth conditions in a low cost culture medium, and characterize the chemical structure of the biosurfactant molecule. The fungal strain UFSM-BAS-01 was isolated from soil contaminated with hydrocarbons and identified as Fusarium fujikuroi. To optimize biosurfactant production, a Plackett–Burman design and a central composite rotational design were used. The variables evaluated were pH, incubation period, temperature, agitation and amount of inoculum in a liquid medium containing glucose. The partial structure of the biosurfactant molecule was identified by nuclear magnetic resonance spectrometry. F. fujikuroi reduced surface tension from 72 to 20 mN m−1 under the optimized conditions of pH 5.0, 37 °C and 7 days of incubation with 190 rpm agitation. The partial identification of the structure of the biosurfactant demonstrated the presence of an α,β-trehalose. The present study is the first report of the biosynthesis of this compound by F. fujikuroi, suggesting that the biosurfactant produced belongs to the class of trehalolipids.

This study investigated the potential of Brazilian kaolin as a low-cost adsorbent for the removal of Malachite Green (MG) from colored effluents. The morphology, chemical structure and surface properties of the adsorbent were investigated by characterization techniques such as X-ray diffraction, N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, X-ray fluorescence spectrometry, scanning electron microscopy, thermogravimetric analysis and particle size distribution. A possible technological application of raw kaolin is the MG removal from aqueous media, which was investigated using batch adsorption experiments. The adsorption kinetics was studied using the pseudo-first order, pseudo-second order and Elovich models. The adsorption isotherms were studied using the Langmuir, Freundlich and Sips models. The Elovich model was the more adequate to represent the adsorption kinetic, while the equilibrium was well represented by the Langmuir model. The maximum adsorption capacity, at pH of 6.3 and temperature of 25ºC, was 128 mg g-1, and this satisfactory result may be associated with some adsorbent properties. Therefore, the results revealed that raw kaolin can be utilized as a promising low-cost adsorbent to remove MG from colored effluents.

Nickel ferrite/multi-walled carbon nanotubes (NiFe2O4/MWCNTs) composite has been rapidly synthesized via microwave irradiation technique. The structural properties of the product was investigated by X-ray diffraction (XRD), N2 adsorption/desorption isotherms, thermogravimetric analysis (TGA), Raman spectroscopy and, scanning electron microscopy (SEM). Catalytic behavior of the composite material on the advanced photo-Fenton degradation of Amaranth dye was evaluated. The synthesis conditions employed on the microwave system were: temperature (235 °C), power (500 W), pressure (600 psi) and irradiation time (30 min). Characterization results showed the formation of hybrid material, containing a predominantly microporous structure, with surface area and total pore volume of 54 m2 g-1 and 0.2249 cm3 g-1, respectively. The composite exhibited higher catalytic activity compared to the pure NiFe2O4, reaching 100% of decolorization at 60 min of reaction, which can be attributed to a synergism between NiFe2O4 and MWCNTs. Therefore, NiFe2O4/MWCNTs composite can be used as a promising photo-Fenton catalyst to degrade Amaranth dye from aqueous solutions.

Mesoporous Fe2O3-supported ZSM-5 zeolites were prepared by carbon-templating and subsequently evaluated as photo-Fenton catalysts to degrade a dye used as a model heavy organic pollutant. The synthesis procedure of the mesoporous ZSM-5 zeolites was performed employing a nucleating gel and carbon particles as mesopores template. Thereafter, the precursor salt of the iron oxide (Fe2O3) was impregnated and then calcined to obtain the final catalyst. For comparison purposes, a conventional Fe2O3-supported ZSM-5 zeolite was also prepared. The results showed that the amount of intracrystalline mesopores formed in the ZSM-5 crystals was influenced by the amount of carbon added into the synthesis mixture. In comparison to the conventional prepared catalyst, the mesoporous Fe2O3/ZSM-5 ones showed an improved performance in the degradation of the target organic pollutant by the photo-Fenton reaction, which was attributed to the improvement of their textural properties as consequence of the mesopores generation.

ZnWO4 particles were synthesized as a single-phase by a simple and easy solvo-hydrothermal technique using water-ethylene glycol mixture as solvent, without using surfactant. Physical properties of produced particles were analyzed by X-ray diffraction (XRD), infrared spectroscopy (FTIR), surface area (BET), particles size distribution and atomic force microscopy (AFM). This material was used as support for inulinase immobilization by physical adsorption and the influence of temperature (30 and 50 ºC) was evaluated. Material with mesoporous characteristic and with a surface area of 35.5 m2.g-1 was obtained. According to the findings, ZnWO4 present a satisfactory inulinase adsorption, and the better result was 605 U.g-1 support at 30 ºC. Therefore, ZnWO4 particles prepared by one-step solvo/hydrothermal route provide a new potential support for inulinase immobilization.

Este estudio evaluó experimentalmente el comportamiento de una columna de destilación de etanol/agua a pequeña escala. Se realizó análisis estadístico utilizando el software Statistica® 7,0, considerando un nivel de significación del 90% (p < 0,10), para evaluar si las variables independientes (concentración de etanol y caudal de alimentación) influencian la producción de etanol de acuerdo con la legislación brasileña, i.e., etanol combustible con concentración de etanol entre 92,5 y 93,8 % en masa. Los resultados demostraron que la influencia de la concentración de etanol y el caudal de alimentación fueron significativos para la concentración del producto destilado y la tasa de recuperación. La tasa de recuperación de etanol fue mayor que 80%, lo que señala que el rendimiento de la columna a pequeña escala fue satisfactorio.

This research assessed experimentally the performance of a small-scale ethanol/water distillation column. Statistical analysis was performed using Statistica® 7.0, considering a significance level of 90% (p < 0.10), to evaluate if the independent variables (feed stream ethanol concentration and flow rate) influence on the production of ethanol in accordance with the Brazilian legislation, i.e., a Hydrous Ethanol Fuel with ethanol content between 92.5 and 93.8 wt%. The results demonstrated that the influence of the feed stream ethanol concentration and flow rate were significant for both the top product concentration and the recovery ratio. The recovery ratio of ethanol was above 80%, demonstrating that the performance of the small-scale column is satisfactory.

AbstractCopper and cobalt aluminates were obtained through the use of chitosan as template. In this synthesis route, chitosan is eliminated by heating, and a porous material is produced. These oxides were used as supports for inulinase immobilization by adsorption process. Physical properties of produced particles were analyzed by X-ray diffraction (XRD) and nitrogen adsorption-desorption isotherms. Both oxides presented particles containing mesoporous characteristics and high surface area, which is desirable for applications in enzyme immobilization processes. The results revealed that the copper and cobalt aluminates exhibit high inulinase immobilization efficiencies, which makes them promising supports for enzyme immobilization.

Neste trabalho, foi avaliada a produção de biobutanol por Clostridium beijerinckiiNRRL B-592 usando o caldo de sorgo sacarino como fonte de carbono. Foram avaliadas as variáveis operacionais como pH e densidade de inóculo, bem como a suplementação de meios industriais com extrato de levedura e triptona. A máxima concentração de butanol obtida foi de 2,12g kg-1, utilizando 12,5% de inóculo, 0,05g 100mL-1 de triptona e 0,1g 100ml-1 de extrato de levedura e pH inicial de 5,5. A principal contribuição deste trabalho foi o de mostrar um procedimento sistemático para o desenvolvimento de um meio industrial de baixo custo para a produção de biobutanol a partir de sorgo sacarino.

In this research it was evaluated the production of biobutanol by Clostridium beijerinckiiNRRL B-592 using sweet sorghum juice as carbon source. Operational variables, like pH and initial inoculum size, as well as supplementation of industrial media with yeast extract and tryptone, were evaluated. The maximum butanol obtained was 2.12g kg-1 using 12.5% of inoculum size, 0.05g 100mL-1 of tryptone and 0.1g 100mL-1 of yeast extract and initial pH of 5.5. The main contribution of this research was to show a systematic procedure for development of a low cost industrial media for biobutanol production from sweet sorghum.

ZnAl2O4 spinel was synthesized by co-precipitation using ammonia as precipitating agent, followed by thermal treatment at 750 ºC. The structural properties of particles were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), differential thermal analysis (DTA), and N2 adsorption/desorption isotherms (BET) techniques. The photocatalytic activity was evaluated in the degradation of organic pollutant in aqueous solution under sunlight. The results showed that the ZnAl2O4 particles exhibited a mesoporous structure, and a promising photocatalytic activity for the degradation of pollutant molecules.

In this work was investigated the influence of pH on the synthesis of struvite using cola beverage waste as source of phosphorus. The process was operated in a batch reactor. The reaction time was 20 minutes, and the chemicals MgCl2.6H2O and NH4Cl were used in the experiment, with a molar ratio of Mg+2:NH4+:PO4(3-) = 1:1:1. The products were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), surface area (BET), thermogravimetric analysis (TGA) and infra-red (IR). From the results was verified the formation of a crystalline phase at pH 9.5, with a surface area of 6.59 m² g-1 and a particle size of about 0.25 µm.

Este trabalho teve como objetivo investigar a síntese de fruto-oligossacarídeos (FOS) a partir de inulinase imobilizada de Kluyveromyces marxianus NRRL Y-7571, em meio aquoso e orgânico usando sacarose como substrato. A estratégia sequencial de planejamento experimental foi utilizada para otimizar a produção de FOS em ambos os sistemas. Para o meio orgânico, um planejamento fatorial fracionário 2(6-2) foi utilizado, visando avaliar os efeitos principais da temperatura, concentração de sacarose, pH, razão molar água/solvente orgânico, atividade da enzima e concentração de polietilenoglicol. Para o sistema aquoso, um planejamento composto central, tendo como variáveis independentes a atividade da enzima e a concentração de sacarose, foi utilizado. A maior produção de FOS foi obtida no sistema orgânico (18,2 ± 0,9% (m/v), a 40 ºC, pH 5.0, concentração de sacarose de 60% (m/m), atividade enzimática de 4 U.mL-1 e razão molar água/solvente orgânico de 25/75% (m/m). Em meio aquoso, a maior produção de FOS foi de 14,6 ± 0,9% (m/m) a 40 ºC, pH 5,0, concentração de sacarose de 60% (m/m) e atividade enzimática de 4,0 U.mL-1.

This work investigated the fructooligosaccharides (FOS) synthesis by immobilized inulinase obtained from Kluyveromyces marxianus NRRL Y-7571 in aqueous and aqueous-organic systems using sucrose as substrate. The sequential strategy of experimental design was used to optimize the FOS conversion in both systems. For the aqueous-organic system, a 2(6-2) fractional design was carried out to evaluate the effects of temperature, sucrose concentration, pH, aqueous/organic ratio, enzyme activity, and polyethylene glycol concentration. For the aqueous system, a central composite design for the enzyme activity and the sucrose concentration was carried out. The highest fructooligosaccharides yield (Y FOS) for the aqueous-organic system was 18.2 ± S0.9 wt%, at 40 ºC, pH 5.0, sucrose concentration of 60% (w/w), enzyme activity of 4 U.mL-1, and aqueous/organic ratio of 25/75 wt%. The highest Y FOS for the aqueous system was 14.6 ± 0.9 wt% at 40 ºC, pH 5.0, sucrose concentration of 60 wt%, and enzyme activity of 4.0 U.mL-1.