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SbstractEncapsulation of bioactive compounds has been carried out to improve bioavailability and to protect them against harm conditions. However, encapsulation processes are often aggressive and it is important that encapsulated substances keep their biological activity. In this work curcumin was nanoencapsulated using dichloromethane as solvent and ultrasound as dispersion device. Nanoparticles were obtained using different curcumin concentrations and encapsulants (PLLA and Eudragit S100) and the encapsulation efficiency was inferred using spectroscopic and calorimetric techniques as well as optical microscopy. Total phenolic contents and antioxidant activity tests were applied to the curcumin before and after encapsulation and also to blank polymer nanoparticles. Results demonstrated that the encapsulation process had no deleterious influence on its antioxidant activity.

-Encapsulation of polyunsaturated fatty acid (PUFA)is an alternative to increase its stability during processing and storage. Chia (Salvia hispanica L.) oil is a reliable source of both omega-3 and omega-6 and its encapsulation must be better evaluated as an effort to increase the number of foodstuffs containing PUFAs to consumers. In this work chia oil was extracted and encapsulated in stearic acid microparticles by the hot homogenization technique. UV-Vis spectroscopy coupled with Multivariate Curve Resolution with Alternating Least-Squares methodology demonstrated that no oil degradation or tocopherol loss occurred during heating. After lyophilization, the fatty acids profile of the oil-loaded microparticles was determined by gas chromatography and compared to in natura oil. Both omega-3 and omega-6 were effectively encapsulated, keeping the same omega-3:omega-6 ratio presented in the in natura oil. Calorimetric analysis confirmed that encapsulation improved the thermal stability of the chia oil.

Clomazone has excelled among Brazilian non-target-site herbicides with high environmental impact. Its high solubility in water can result in leaching, contaminating groundwater and watercourses with possible riparian forest degradation. This situation can be mitigated by phytoremediation process. This study aimed to identify tree species tolerant to clomazone aiming to use them in bioremediation programs. Twelve forest species were evaluated: Inga marginata Willd, Handroanthus serratifolius (A.H. Gentry) S. Grose, Jacaranda puberula Chan, Cedrela fissilis Vell, Calophyllum brasiliense Cambess, Psidium myrsinoides Berg, Tibouchina granulosa Cogn, Caesalpinia ferrea Mart ex. Tul, Caesalpinia pluviosa DC, Terminalia argentea Mart & Zucc, Schinopsis brasiliensis Eng and Schizolobium parahyba (Vell). The statistical analysis was performed in a completely randomized block design with four replications. Three clomazone applications were made each 20 days (60, 80 and 100 days after planting); each application was equivalent to one-half of the recommended rate (2.0 L ha -1 ). The evaluated parameters were plant height, stem diameter, leaf number, leaf area and dry biomass. The forest species survived the clomazone application; and I. marginata, C. ferrea and S. brasiliensis showed increased tolerance to this herbicide, demonstrating potential for phytoremediation of areas contaminated by clomazone.

Spectroscopic techniques have great potential to evaluate soil properties. However, there are still questions regarding the applicability of spectroscopy to analyze soil phosphorous (P) availability, especially in tropical soils with low nutrient contents. Therefore, this study evaluated the possibility to estimate P availability in soil and its pools (labile, moderately labile and non-labile) via Vis-NIR spectroscopy based on intra-field calibration. We used soils from two different locations, a plot experiment that received application of phosphate fertilizers (Field-A) and a cultivated field where a grid soil sampling was performed (Field-B). We used the technique of diffuse reflectance in the visible and near-infrared (Vis-NIR) to obtain the spectra of soil samples. Predictive modeling for P availability and labile, moderately labile and non-labile pools of P in soil were obtained via partial least squares (PLS) regression; classification modeling was performed via Soft Independent Modeling of Class Analogy (SIMCA) on three P availability levels in order to overcome the limitation on quantifying P via Vis-NIR spectroscopy. We found that isolating P contents as the only variable (Field-A), Vis-NIR spectroscopy does not allow estimating P pools in the soil. In addition, quantification of P available in the soil via predictive modeling has limitations in tropical soils. On the other hand, estimating P content in soil through classes of availability is a feasible and promising alternative.

RESUMO Os tijolos e blocos cerâmicos são empregados em larga escala nas construções das alvenarias de vedação ou estruturais, proporcionando condições adequadas de conforto ao ambiente interno. Na fabricação desses elementos cerâmicos há necessidade de se excluir as peças com defeitos, originados da não conformidade das dimensões, das falhas no processo de queima ou quebras. O simples descarte dessas peças com defeito em aterros gera custos de remoção e impactos ambientais, bem como o desperdício de um material que contém suas propriedades físicas e mecânicas inerentes. Nesse contexto, o presente trabalho teve como objetivo avaliar, sob os aspectos da resistência à compressão e econômicos, a viabilidade do emprego de agregados oriundos do resíduo de tijolos cerâmicos na dosagem de concreto para produção de blocos maciços para pavimentação e para alvenaria. Para tanto, foram triturados tijolos cerâmicos, em moinho de martelos e elaboradas misturas de concreto com substituição dos agregados (miúdo e graúdo). O desempenho mecânico dos blocos produzidos foi avaliado por ensaio à compressão simples e a viabilidade econômica para implantação do processo de aproveitamento dos resíduos foi analisada para cenários com um horizonte de cinco anos, utilizando o fluxo de caixa para calcular o retorno do investimento inicial. Os resultados mostraram que os blocos produzidos com a substituição de 80% do agregado miúdo apresentaram um elevado desempenho mecânico e comprovada viabilidade econômica. Com base nestes resultados, conclui-se que a produção de blocos para pavimentação e alvenaria é uma solução viável para o aproveitamento e destino dos resíduos da indústria cerâmica.

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