RESUMEN La familia botánica Solanaceae tiene muchas especies que producen compuestos con propiedades insecticidas, e.g. nicotina y capsaicina, que se utilizan para el control de plagas en la agricultura. Este hecho proporciona perspectivas promisorias para identificar compuestos insecticidas en especies nativas brasileñas de Solanaceae. En el presente estudio se llevó a cabo un cribado con 25 extractos etanólicos de 17 especies de Solanaceae con el propósito de evaluar su bioactividad sobre el gorgojo pinto del frijol, Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae). La bioactividad de los extractos etanólicos se evaluó por experimentos de contacto residual. Los adultos de Z. subfasciatus se expusieron a los frijoles tratados con los extractos y se midió la mortalidad de los adultos, la ovoposición, la progenie F1 y el daño en los granos. La mayoría de los extractos etanólicos redujeron el número de huevos, la viabilidad de los huevos, la progenie y el daño en los granos, pero ninguno de ellos interfirió en la proporción sexual de los insectos. El extracto etanólico de las hojas de Solanum lycocarpum A. St.-Hil promovió los efectos más prometedores sobre Z. subfasciatus. Este extracto puede ayudar a controlar a Z. subfasciatus en frijoles almacenados, principalmente a los pequeños agricultores y a los agricultores orgánicos.

ABSTRACT The botanical family Solanaceae has many species producing compounds with insecticidal properties, e.g. nicotine and capsaicin, which are used for pest management in agriculture. This fact provides perspectives to identify insecticidal compounds in Brazilian native species of Solanaceae. In this study, we performed a screening with 25 ethanolic extracts from 17 Solanaceae species in order to evaluate their bioactivity against the Mexican bean weevil, Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae). The bioactivity of Solanaceae ethanolic extracts (2,500 mg kg-1) was tested with residual contact bioassays. Adults of Z. subfasciatus were exposed to treated bean grains, and adult mortality, oviposition, F1 progeny and damages on grains were quantified. Most of the ethanolic extracts from Solanaceae reduced the number of eggs per sample, the egg-adult viability, the F1 progeny and the damages on bean grains promoted by Z. subfasciatus, but none of them interfered on its sex ratio. Ethanolic extract from leaves of Solanum lycocarpum A. St.-Hil promoted the most promissory effects on Z. subfasciatus. This ethanolic extracts can be a suitable alternative to control Z. subfasciatus in stored beans, mainly for small farmers and organic farmers.

ABSTRACT Uptake of nutrients and cadmium (Cd) are dependent upon many factors, including plant species, ions concentration and pH. Tolerance to Cd-induced oxidative stress can be modulated by phytohormones such as abscisic acid (ABA), which induce the production of reactive oxygen species, activating proteins and enzymes involved in stress response and possibly stress tolerance. The present study aimed to evaluate the biochemical variations induced by Cd in ABA-deficient sitiens tomato mutant (sit) and its wild-type counterpart, Micro-Tom (MT), grown at different pH conditions. The plants were cultivated in nutrient solution (pH 5, 6 and 7; 20-days) and were then further grown over a 48-h period in 0 or 50 ?M CdCl2 at pH 6. Before Cd addition, the concentrations of nitrogen, sulfur, copper, iron and zinc were determined and variations in nutrients concentrations were observed. After Cd addition, sit roots grown at pH 5 and 7 did not exhibit differences in ascorbate peroxidase (APX) activity in 0 or 50 ?M CdCl2, and sit root grown at pH 6 exhibited lower glutathione reductase (GR) activity in the presence of Cd. Moreover, sit shoot grown at pH 5 showed decreased activities of superoxide dismutase (SOD), Mn-SOD II and Cu/Zn-SOD V, in 0 and 50 ?M CdCl2. The results indicated that pH modulates the plant nutrition in a complex way and may involve multiple ABA signaling pathways. Likewise, ABA status seems to be related with the Cd-translocation within the plant, suggesting that Cd, ABA and pH responses cannot be evaluated as isolated systems.

Abstract Coffee is one of the most consumed beverages in the world. Its chemical composition may have varied according to the planting site, degree of roasting, and method of preparation. This work aimed to evaluate the antioxidant activity of coffee from the region of Cerrado in the State of Minas Gerais, Brazil. The evaluation was performed with samples roasted at two different levels (traditional and extra dark) and using two different preparation methods (decoction and infusion) that reflect the conditions of preparing coffee. In vitro antioxidant activity by ABTS and DPPH radical methods and the concentration of total phenolic compounds and caffeine were determined. Samples made by decoction showed a higher content of phenolic compounds and no significant difference was observed between the degrees of roasting. However, the antioxidant activity and caffeine concentration of the extra dark samples were higher than those of the traditional samples for both preparation methods. The decoction preparation method was better for extracting phenolic compounds and the extra dark roast showed a higher concentration of caffeine and antioxidant activity. The samples showed a high antioxidant activity, indicating the coffee from Cerrado is an important source of antioxidants.

RESUMO O carvão vegetal é um produto bastante utilizado para a cocção de alimentos, porém, a sua qualidade para o referido uso não tem sido bem estudada. Os hidrocarbonetos policíclicos aromáticos (HPAs) são uma classe de compostos carcinógenos que podem estar presentes no carvão vegetal. Dessa forma, o objetivo deste estudo foi analisar o composto orgânico líquido extraído do carvão vegetal pela ação de solventes orgânicos, quanto à presença de HPAs. Para isso, foi adquirida uma marca comercial de carvão, coletada em estabelecimentos comercias em Piracicaba, SP. Foram realizados ensaios complementares para identificação da madeira utilizada na produção do carvão, determinação da umidade, densidade aparente, composição imediata, poder calorífico e índice de combustão. O composto orgânico extraído do carvão vegetal a partir da dissolução em ciclohexano foi analisado por meio de cromatografia a gás acoplado a um espectrômetro de massa (GC/MS), com intuito de determinar uma classe de dezesseis HPAs. De forma geral, o carvão vegetal apresentou características regulares para utilização em cocção de alimentos. Todos os HPAs analisados foram detectados no composto orgânico extraído do carvão, porém os valores observados estiveram abaixo do limite de quantificação determinado.

ABSTRACT Charcoal is a widely used product for barbecue, however, its quality for said use has not been well studied. Polycyclic aromatic hydrocarbons (PAHs) are a class of carcinogenic compounds that can be present in charcoal. Thus, the objective of this study was to analyze the organic phase extracted from charcoal by organic solvents, regarding the presence of PAHs. For this, a commercial charcoal brand was acquired, collected in establishments in the city of Piracicaba, São Paulo. Complementary tests were carried out to identify the wood used in the production of charcoal, such as determination of humidity, apparent density, immediate composition, calorific value, and combustion index. The organic phase extracted from the charcoal using cyclohexane was analyzed in a gas chromatograph coupled to a mass spectrometer (GC/MS) for identification of a class of sixteen PAHs. In general, charcoal presented regular characteristics for barbecue. All PAHs analyzed were detected in the organic phase extracted from the charcoal, but the observed values were below the quantified limit determined