Resumo A cultura do milho, por sua fácil adaptação aos mais diversos agroecossistemas, se espalha por diferentes regiões do mundo, tornando-se uma das mais importantes culturas agrícolas. Nesta cultura, os insetos-praga se destacam por causar prejuízos tanto no campo quanto nos armazéns. A aplicação de óleos essenciais pode ser uma importante técnica a ser investigada no manejo de insetos devido à sua conhecida atividade inseticida e baixo risco o meio ambiente. O objetivo do deste trabalho foi avaliar o efeito inseticida e repelente de óleos essenciais de capim-limão exótico (Cymbopogon citratus) e capim-limão nativo (Elionurus sp.) para o manejo do gorgulho do milho (Sitophilus zeamais (Mots., 1855, Coleoptera: Curculionidae). A análise química dos óleos feita por CG-MS mostrou que a composição química do capim-limão nativo e exótico é semelhante, entretanto, as espécies exóticas apresentaram maior número de compostos. Os óleos essenciais de capim-limão nativo e exótico têm eficiência na mortalidade do gorgulho do milho, e verifica-se que o aumento na dose aplicada reflete na redução do tempo de exposição do inseto até que ocorra a morte. O óleo essencial de ambas as espécies apresentou capacidade repelente em todos os momentos avaliados. Assim, pode-se afirmar que ambas as espécies possuem capacidade e potencial para serem utilizadas no manejo do gorgulho do milho, podendo ser uma alternativa para a agricultura familiar e produção orgânica.

Abstract Corn crop, due to its easy adaptation to the most diverse agroecosystems, spreads throughout the different regions of the world, making it one of the most important agricultural crops. In this crop, pest insects stand out for causing losses both in the field and in warehouses. The application of essential oils can be an important technique to be investigated in the management of insects due to its known insecticidal activity and low risk to the environment. The objective of the work was to value the insecticide and repellent effect of essential oils of exotic lemongrass (Cymbopogon citratus) and native lemongrass (Elionurus sp.) for the management of maize weevil (Sitophilus zeamais (Mots., 1855, Coleoptera: Curculionidae)). The chemical analysis of the oils made by CG-MS showed that the chemical composition of the native and exotic lemongrass is similar, however, the exotic species presented a greater number of compounds. The essential oils of native and exotic lemon grass have efficiency on maize weevil mortality, and it is verified that the increase in the applied dose reflects in a reduction in the insect's exposure time for death to occur. The essential oil of both species showed repellent capacity at all times evaluated. Thus, it can be said that both species have the capacity and potential to be used in the management of corn weevil, and can be an alternative for smallhorders farmers and organic production.

Resumo Campomanesia xanthocarpa, planta pertencente à família Mirtaceae, é popularmente conhecida como gabiroba. Folhas da gabiroba são popularmente usadas para tratar de doenças inflamatórias, renais, digestivas entre outras. Além disso, estudos têm mostrado um efeito redutor dos níveis de colesterol. O objetivo deste estudo foi avaliar os efeitos anti-hiperglicêmico e hipolipidêmico do extrato de sementes de Campomanesia xanthocarpa em ratos hiperglicêmicos. Os resultados mostraram que 400 mg/kg do extrato da semente foi capaz de reduzir os níveis de glicose sanguínea e aumentar o conteúdo de glicogênio hepático e muscular, bem como inibir a atividade da maltase e sacarase. Na dose de 200 mg/kg e 800 mg/kg, a atividade das enzimas também foi reduzida. No perfil lipídico, 400 mg/kg produziu uma redução nos níveis séricos de colesterol total e LDL e com 200 mg/kg houve um aumento nos níveis de colesterol HDL. O extrato não apresentou efeitos tóxicos hepáticos e renais nas doses testadas. Os resultados sugerem que o tratamento com o extrato de Campomanesia xanthocarpa é eficaz na redução da glicemia, de colesterol total e LDL com potencial para tratamento adjuvante do diabetes e hipercolesterolemia, no entanto estudos farmacológicos e toxicológicos adicionais são necessários.

Abstract Campomanesia xanthocarpa, a plant belonging to the Myrtaceae family, is popularly known as gabiroba. Leaves of gabiroba has been popularly used to treat various diseases, including inflammatory, renal, and digestive, among others. Additionally, studies have shown an effect to reduce blood cholesterol levels. The aim of this study was to evaluate the antihyperglycemic and hypolipidemic effects of Campomanesia xanthocarpa seed extract in hyperglycemic rats. The results showed that 400 mg/kg of seed extract was able to decrease blood glucose levels and to increase the muscular and hepatic glycogen content as well as to inhibit the sucrase and maltase activity. At doses of 200 mg/kg and 800 mg/kg, the activity of these enzymes was also reduced. In the lipid profile 400 mg/kg produced a decrease in total and LDL cholesterol serum levels; and with 200 mg/kg there was an increase in HDL cholesterol levels. The extract did not present hepatic and renal toxic effects at the different doses tested. The results suggest that the treatment with Campomanesia xanthocarpa seeds extract is useful in reducing glycemia, total cholesterol and LDL levels with potential adjuvant therapeutic in the treatment of diabetes and hypercholesterolemia, however, additional pharmacological and toxicological studies are still required.

Technologies developed in the last decade have made viable the use of lignocellulosic materials for the production of ethanol. However, to improve the fermentative yield some improvements are necessary, among them the search for new microorganisms capable of fermenting sugars with five carbons. Thus, the present research aimed to determine the best pH and temperature for Pichia membranifaciens LJ04 in synthetic medium containing pentose, aiming at the biotechnological production of ethanol from hemicellulosic hydrolysate. The experimental design was completely randomized in Split-Split-Plot, with 3 replicates. The main treatments were pHs (3.5, 4.0 and 4.5), the secondary were temperatures (32 ºC, 37 ºC and 40 ºC) and the tertiary were fermentation periods (0, 6, 12 and 24 hours). It was determined in this study that the ideal conditions were temperature of 32 ºC and pH 4.0-4.5. With these conditions there was higher xylose consumption, high ethanol production, low production of secondary compounds and high rates of cell viability during fermentation.