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Guarapuava, Brazil

Sarto M.V.M.,Sao Paulo State University | Lana M.C.,West Parana State University | Rampim L.,State University of Midwest | Rosset J.S.,State University of Mato Grosso do Sul | And 2 more authors.
Australian Journal of Crop Science | Year: 2016

Calcium silicate (CaSiO3) applied to the soil may increase Si content in the soil and plants, as well as reduce sweating and increase water use efficiency. In this study, we aimed to investigate whether the application of CaSiO3 increased Si content in plants and interfered with gas exchange and production components in Brachiaria. The experiment was performed using 8-L plastic pots in a greenhouse. Treatments were arranged in a randomized block design in a 3 × 5 factorial: three soils (Rhodic Acrudox, Rhodic Hapludox, and Arenic Hapludult) and five silicate rates (0, 1, 2, 4, and 6 t ha-1 of CaSiO3/MgSiO3) were used; four replications were performed. CaSiO3 application to the soil increases Si concentration in the leaves. Si in plants reduces internal CO2 concentration and increases the efficiency of water use and instantaneous carboxylation efficiency. In soils with low pH and a high Al+3 level, which is toxic, reduction in plant sweating increases the intrinsic efficiency of water use in Brachiaria. Si helped to alleviate the toxic effects of Al+3. Source

De Moraes A.,Federal University of Parana | Carvalho P.C.D.F.,Federal University of Rio Grande do Sul | Anghinoni I.,Federal University of Rio Grande do Sul | Lustosa S.B.C.,State University of Midwest | And 2 more authors.
European Journal of Agronomy | Year: 2014

In the subtropical region of Brazil, integrated crop-livestock systems (ICLSs) are characterized by the annual rotation of pastures and crops in a no-till system where the pasture component is used to produce either meat or milk. These systems focus on integration within the farm rather than between farms, being characterized by alternating cropping and pasturing in the same area. Independent of the crop rotations possible in a subtropical environment, the main integrated farming system found was rotation or succession of summer crops (Glycine max, Zea mays, Phaseolus vulgaris or Oryza sativa) with winter annual grazing grasses (mixed or solely Avena strigosa and Lolium multiflorum) or successive natural pastures. The high variability of crop yield in the Brazilian subtropics (due to climate extremes) as well as associated high costs and low prices has encouraged farmers to integrate livestock into their enterprises as a low-risk diversification option. Long-term experiments have demonstrated the benefits of crop-livestock integration with respect to many aspects of the soil-plant-animal system. There is evidence that such a system is not only a livestock-agriculture combination but also a unique system reaching a new complexity threshold, resulting in emergent properties with novel functionalities, some of which have yet to be investigated. In addition to greater environmental gains with less vulnerability, there are higher yields and more financial gain by the farmer, compared to that in the use of monocultures or non-integrated livestock farming. We conclude that ICLSs in Subtropical Brazil provide the opportunity for intensification with sustainability. © 2013 Elsevier B.V. Source

Mesomo M.C.,Federal University of Parana | Mesomo M.C.,State University of Midwest | Scheer A.D.P.,Federal University of Parana | Perez E.,State University of the Central West | And 2 more authors.
Journal of Supercritical Fluids | Year: 2012

This work reports the extraction of ginger (Zingiber officinale Roscoe) roots using sub and supercritical CO 2 and compressed propane as solvents. Antioxidant activity effect and phenolic content were evaluated on the extracts obtained. The extractions were performed in a laboratory scale unit at pressures of 8.0 MPa, 16.5 MPa and 25.0 MPa using CO 2 and 3.0 MPa, 6.5 MPa and 10.0 MPa using propane, and at 293.15 K, 313.15 K and 333.15 K for both solvents. The operating conditions tested achieved a maximum yield of 3.21 wt% for the CO 2 extraction and 2.75 wt% for the extraction using propane as solvent. When CO 2 was used as solvent, the pressure and temperature presented significant effect on the extraction yield. When propane was used, the most important variable was the pressure that presented a positive effect on the extraction yield. The chemical profiles were determined by gas chromatography and were similar for the two solvents, in which the main compounds were α-zingiberene, β-sesquiphellandrene, α-farnesene, geranial, β-bisabolene and β-eudesmol. The antioxidant activity assays were performed on the extracts obtained using the phosphomolybdenum reducing method. The extracts obtained using supercritical CO 2 and compressed propane presented antioxidant effects. The highest antioxidant activity (931.67 ± 2.51 mg of α-tocopherol/g of extract) was found for extracts obtained using supercritical CO 2 as solvent at 313.15 K and 16.5 MPa. © 2012 Elsevier B.V. All rights reserved. Source

Czaikoski K.,Federal University of Parana | Mesomo M.C.,State University of Midwest | Scheer A.D.P.,Federal University of Parana | Queiroga C.L.,University of Campinas | And 2 more authors.
Journal of Essential Oil Research | Year: 2016

This article reports a study on the extraction and evaluation of essential oil obtained from dried flowers of Eupatorium intermedium, a plant native to southern Brazil that belongs to the Asteraceae family. The hydrodistillation achieved a maximum yield of 1.01 wt% of essential oil. Regarding the chemical composition, by a qualitative analysis, the identified substances were α-pinene, sabinene, β-pinene, limonene, caryophyllene (E), germacrene D, spathulenol and caryophyllene oxide. The antioxidant activity of the essential oil obtained was evaluated using the DPPH method, phosphomolybdenum reducing method and total phenolic content. The total phenolic content was 4.26 mg GAE/g of oil. The antioxidant activity obtained by the DPPH method was 0.82 wt%, at a concentration of 250 mg/mL. The antioxidant activity obtained through the reduction of the phosphomolybdenum complex was 1154.69 mg α-tocopherol/g of oil. Antibacterial activity assays were performed using the agar well method. The oil presented antibacterial effects against the Gram-positive bacteria tested. © 2016 Informa UK Limited, trading as Taylor & Francis Group Source

Reis J.S.S.,Federal University of Para | Oliveira G.B.,Federal University of Para | Monteiro M.C.,Federal University of Para | Machado C.S.,State University of Midwest | And 3 more authors.
Phytomedicine | Year: 2014

Purpose Propolis biological effects are mainly attributed to its polyphenolic constituents such as flavonoids and phenolic acids that were recently described in the chemical composition of an extract of propolis obtained with edible vegetal oil (OEP) by our group. The aim of this study was to evaluate the effect of OEP on the behavior of rats. Materials and methods An in vivo open field (OF), elevated Plus-maze (EPM), and forced swimming (FS) tests were performed to evaluate locomotor activity, anxiolytic- and antidepressant effects of the extract. Besides, oxidative stress levels were measured in rat blood samples after the behavioral assays by evaluation of the Trolox equivalent antioxidant capacity (TEAC) and nitric oxide levels. Results OEP increased locomotion in the OF test (50 mg/kg) and central locomotion and open arm entries in the OF and EPM tests (10-50 mg/kg) and decreased the immobility time in the FS test (10-50 mg/kg). Moreover, OEP reduced nitric oxide levels in response to swim stress induced in rats. Conclusion OEP exerted stimulant, anxiolytic and antidepressant effects on the Central Nervous System and antioxidant activity in rats, highlighting propolis as a potential therapeutic compound for behavior impairment of anxiety and depression. © 2014 Elsevier GmbH. All rights reserved. Source

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