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Campos V.C.A.,State University of Feira de Santana | Lima-Brito A.,Programa de Pos graduacao em Botanica | de Gutierrez I.E.M.,Programa de Pos graduacao em Biotecnologia | de Santana J.R.F.,UEFS
Ciencia Rural | Year: 2013

Umburana de cheiro is a species native to the Caatinga, widely used by local people, beca-use the value oftimber, ornamental, forage and especially medicinal. Considering the significant risk of extinction and the ausence of studies related to the cultive and propagation, the aim of this work was to establish a protocol for micropropagation Amburana cearensis. For this, we evaluated the influence of plant growth regulator BAP at five different concentrations (0.0, 2.22, 4.44, 8.88 and 17.76mM) on the in vitro multiplication of different explants (nodal segments, apex cotyledon and stem segment) and the rooting stage we tested different concentrations of IBA (0.0, 2.5, 5.0 and 10.0mM) in the presence and absence of 1.0g L1 of activated charcoal. Highest number of shoots (2.36) was obtained in 4.44mM of BAP from cotyledonary segment and higher rooting percentage (92.0%) ocurred in 10.0mM of IBA in the absence of activated charcoal. There were no difficulties to the establishment of micropropagation protocol A. cearensis.

Roca R.A.,Federal University of São Carlos | Sczancoski J.C.,São Paulo State University | Nogueira I.C.,Federal University of Maranhão | Fabbro M.T.,Federal University of São Carlos | And 9 more authors.
Catalysis Science and Technology | Year: 2015

In this paper, we have combined the various experimental results and first-principles calculations with a new and interesting discussion to explain the photocatalytic and antibacterial activities of α-Ag2WO4 crystals, which were obtained using the microwave-hydrothermal (MH) method with anionic surfactants. The advantages of the insights gained through the present work are two-fold. First, the mechanism and origin of the photocatalytic and antibacterial activities can be rationalized. Second, this facile and controllable synthetic method is expected to encourage the synthesis of complex metal oxides with specific active facets, and these insights can contribute to the rational design of new materials for multifunctional applications. X-ray diffraction and Rietveld refinement analysis confirmed that all the crystals have an orthorhombic structure without deleterious phases. Ultraviolet-visible diffuse reflectance spectroscopy indicated the presence of intermediary energy levels and a variation in the optical band gap values (3.09-3.14 eV) with the crystal growth process. The geometry, electronic properties of the bulk, and surface energies of these crystals were evaluated using first-principles quantum mechanical calculations based on the density functional theory. The crystal shapes was experimentally and theoretically modeled based on Rietveld refinement data, emission scanning electron microscopy images, and Wulff construction. To obtain a wide variety of crystal shapes, the morphologies were gradually varied by tuning the surface chemistry, i.e., the relative stability of the faceted crystals. The growth mechanisms of different α-Ag2WO4 crystals and their facet-dependent photocatalytic and antibacterial performances were explored in details. The combination of experimental and theoretical data revealed the presence of (110) and (011) planes with high surface energies together with the disappearance of faces related to the (010)/(010) planes in α-Ag2WO4 crystals are key factors that can rationalize both the photocatalytic and antibacterial activities. The different activities may be attributed to the different number of unsaturated superficial Ag and W atoms capable of forming the main active adsorption sites. Finally, we discuss how knowledge of surface-specific properties can be utilized to design a number of crystal morphologies that may offer improved performance in various applications. This journal is © The Royal Society of Chemistry.

Rodrigues J.A.G.,Programa de Pos graduacao em Biotecnologia | Vanderlei E.S.O.,Programa de Pos graduacao em Bioquimica | Quindere A.L.G.,Programa de Pos graduacao em Bioquimica | Fontes B.P.,Programa de Pos graduacao em Bioquimica | And 2 more authors.
Acta Scientiarum - Biological Sciences | Year: 2011

The reportedly low standard quality of heparin (HEP) for use in cardiac surgeries has led to concern in the Brazilian and international markets. Sulfated polysaccharides (SPs) from seaweeds have been regarded as promising substitutes for HEP. The aim of this study was to sequentially extract total SPs (TSPs) from Caulerpa cupressoides (Chlorophyceae) with papain in 100 mM sodium acetate buffer (pH 5.0) containing 5 mM cysteine and 5 mM EDTA, followed by fractionation by ion-exchange chromatography (DEAE-cellulose), and then evaluate the anticoagulant potential of SP fractions by activated partial thromboplastin time (APTT) using normal human plasma and compare it to standard HEP (193 IU mg-1). The obtained fractions were chemically characterized by chemical composition and agarose gel electrophoresis. The yield was 4.61%, and three fractions of SP (F I, F II and F III) eluted with 0.50, 0.75 and 1.00 M of NaCl, respectively, were observed on chromatography profiles; however, differences in charge densities patterns and degree of resolution among them were revealed by electrophoresis. SPs were capable of modifying APTT only in fractions eluted with 0.75 M of NaCl, whose activities were 23.37 and 25.76 IU mg-1, respectively, and the charge density was prerequisite to activity. Therefore, C. cupressoides is a source of SPs possessing low anticoagulant potential compared to HEP.

Passalacqua T.G.,São Paulo State University | Dutra L.A.,Paulista University | De Almeida L.,São Paulo State University | Velasquez A.M.A.,São Paulo State University | And 8 more authors.
Bioorganic and Medicinal Chemistry Letters | Year: 2015

Abstract Chalcones form a class of compounds that belong to the flavonoid family and are widely distributed in plants. Their simple structure and the ease of preparation make chalcones attractive scaffolds for the synthesis of a large number of derivatives enabling the evaluation of the effects of different functional groups on biological activities. In this Letter, we report the successful synthesis of a series of novel prenylated chalcones via Claisen-Schmidt condensation and the evaluation of their effect on the viability of the Trypanosomatidae parasites Leishmania amazonensis, Leishmania infantum and Trypanosoma cruzi. © 2015 Elsevier Ltd.

de Araujo I.W.F.,Programa de Pos graduacao em Biotecnologia | Rodrigues J.A.G.,Programa de Pos graduacao em Biotecnologia | Vanderlei E.S.O.,Federal University of Ceará | de Paula G.A.,Programa de Pos graduacao em Biotecnologia | And 2 more authors.
Acta Scientiarum - Technology | Year: 2012

Biochemical analyses are important tools for discovering new bioactive compounds for medical clinic. This study aimed at isolating iota-carrageenans (ι-CARs) from Solieria filiformis (Rhodophyta) by enzymatic extraction (EE), refined hot-water extraction (RHWE) and hot-water extraction (HWE), and test (EE, s.c.) their anti-inflammatory effects in the peritonitis model using the Lambda-carrageenan (700 μg cavity -1, i.p.) as an inflammatory stimuli in rats. The activated partial thromboplastin time (APTT) was also evaluated in ι-CARs fractions, obtained by ion-exchange chromatography (DEAE-cellulose), using rabbit plasma and compared to heparin (193 IU mg -1). The results showed that the ι-CARs (EE) (3 or 9 mg kg -1) containing 89.92% total sugars, 29.02% sulfate and absence of contaminant proteins inhibited (p < 0.05) the cellular infiltrate in the peritoneal cavity of the animals, but with 27 mg kg -1 had no anti-inflammatory effect (p > 0.05). Similar chromatography profiles were obtained among the methods; however, with fractions revealing different pattern on charge density by electrophoresis. Fractions had no virtually effects on APTT (1.16, 1.73 and 1.59 IU mg -1 for EE, RHWE and HWE, respectively). Further investigations to better understanding the actions of S. filiformis ι-CARs (EE) in the inflammatory response are suggested.

Rodrigues J.A.G.,Programa de Pos graduacao em Biotecnologia | Vanderlei E.S.O.,Federal University of Ceará | Quindere A.L.G.,Federal University of Ceará | de Queiroz I.N.L.,Federal University of Ceará | And 2 more authors.
Acta Scientiarum - Biological Sciences | Year: 2012

Sulfated polysaccharides (SPs) have attracted growing interest for various biotechnological applications. We evaluated the efficiency of two methods of drying SPs (M I and II) extracted from Halymenia sp Rhodophyceae in order to compare the yield, purification and anticoagulant activity. The total SPs (TSPs) were first extracted with papain in 100 mM sodium acetate (pH 5.0) containing cysteine and EDTA (5 mM). The TSPs obtained were dried in an oven (M I) or lyophilized (M II) and then examined by ion exchange chromatography (DEAE-cellulose) using the NaCl gradient technique. The fractions were analyzed by 0.5% agarose gel electrophoresis and the in vitro anticoagulant activity was evaluated by the activated partial thromboplastin time test using normal human plasma and compared to heparin (HEP) (193.00 IU mg-1). There was a difference in TSP yield of 19.05% and similar chromatographic SP profiles. Electrophoresis revealed fractions with distinct resolutions. The fractions eluted with 0.75 M of salt (M I and II) were the most active, measuring 27.40 and 72.66 IU mg -1, respectively, when compared to HEP. Therefore, obtaining SP with anticoagulant activity from Halymenia sp. is more efficient by freeze-drying.

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