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Acta Alimentaria
Authors: L.B.S. Sabino, M.L.C. Gonzaga, D.J. Soares, A.C.S. Lima, J.S.S. Lima, M.M.B. Almeida, P.H.M. Sousa, and R.W. Figueiredo

This study is aimed at performing the determination of bioactive compounds, antioxidant activity, and the identification of the minerals in the flours produced with the tropical fruit peels of mango, papaya, melon, and pineapple. The results showed that the papaya peel flour has the highest amount of ascorbic acid and lycopene when compared with the other studied flours. The mango peel flour has a high content of total extractable polyphenols and a high antioxidant activity. Regarding the mineral content, the by-product of melon stood out with 523.24±26.12 mg/100 g of potassium, 104.15±3.52 mg/100 g of calcium and 6.62±0.30 mg/100 g of iron. The flours prepared with mango, papaya, melon, and pineapple peels are potential sources of bioactive compounds and minerals, also presenting good antioxidant activity, being, therefore, recommended to be used in food products to improve the nutritional quality of the product.

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Journal of Thermal Analysis and Calorimetry
Authors: Sahra C. Lemos, Silmar J. S. Franchi, Adelino V. G. Netto, Antonio E. Mauro, Oswaldo Treu-Filho, Regina C. G. Frem, Eduardo Tonon de Almeida, and Cláudia Torres

Abstract

This work describes the synthesis, characterization, and the thermal behavior investigation of four palladium(II) complexes with general formulae [PdX2(mba)2], in which mba = N-methylbenzylamine and X = OAc (1), Cl (2), Br (3) or I (4). The complexes were characterized by elemental analysis, infrared vibrational spectroscopy, and 1H nuclear magnetic resonance. The stoichiometry of the complexes was established by means of elemental analysis and thermogravimetry (TG). TG/DTA curves showed that the thermodecomposition of the four complexes occurred in 3–4 steps, leading to metallic palladium as final residue. The palladium content found in all curves was in agreement with the mass percentages calculated for the complexes. The following thermal stability sequence was found: 3 > 2 > 4 > 1. The geometry optimization of 1, 2, 3, and 4, calculated using the DFT/B3LYP method, yielded a slightly distorted square planar environment around the Pd(II) ion made by two anionic groups and two nitrogen atoms from the mba ligand (N1 and N2), in a trans-relationship.

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Journal of Thermal Analysis and Calorimetry
Authors: A. V. G. Netto, A. M. Santana, A. E. Mauro, Regina C. G. Frem, E. T. de Almeida, M. S. Crespi, and H. E. Zorel Jr.
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Journal of Thermal Analysis and Calorimetry
Authors: Ellen Denise P. Almeida, Adjane A. Costa, Mairim R. Serafini, Fábia C. Rossetti, Juliana M. Marchetti, Victor Hugo V. Sarmento, Rogéria de S. Nunes, Mário Ernesto G. Valerio, Adriano A.S. Araújo, and Ana Amélia M. Lira

Abstract

Solid lipid nanoparticles (SLN) without drug and SLN loaded with chloroaluminum phthalocyanine (AlClPc) were prepared by solvent diffusion method in aqueous system and characterized by thermal analyses and X-ray diffraction (XRD) in this study. Determination of particle size, zeta potential (ZP), and encapsulation efficiency were also evaluated. SLN containing AlClPc of nanometer size with high encapsulation efficiency and ZP were obtained. The results indicated that the size of SLN loaded with AlClPc is larger than that of the inert particle, but ZP is not changed significantly with incorporation of the drug. In differential scanning calorimetry (DSC) curves, it was observed that the melting point of stearic acid (SA) isolated and in SLN occurred at 55 and 64 °C, respectively, suggesting the presence of different polymorphs. DSC also shows that the crystallinity state of SLN was much less than that of SA isolated. The incorporation of drug in SLN may have been favored by this lower crystallinity degree of the samples. XRD techniques corroborated with the thermal analytic techniques, suggesting the polymorphic modifications of stearic acid.

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Acta Biologica Hungarica
Authors: L. M. Jesus, P. R. C. Abreu, Marcela C. Almeida, Lavínia C. Brito, Sheila F. Soares, D. E. De Souza, Luciana C. Bernardo, A. S. Fonseca, and M. Bernardo-Filho

Since ancient times propolis has been employed for many human purposes because to their favourable properties. Blood constituents labeled with technetium-99m (99mTc) have been used in nuclear medicine procedures. Some authors have reported that synthetic or natural drugs can interfere with the labeling of blood constituents with 99mTc. The aim of this work was to evaluate the action of a propolis extract on the labeling of blood elements with 99mTc. Samples of whole blood of male Wistar rats were incubated in sequence with an aqueous propolis extract at different concentrations, stannous chloride and 99mTc, as sodium pertechnetate. Blood samples were centrifuged to separate plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were also separated after precipitation in trichloroacetic acid solution and centrifugation. The radioactivity was counted and the percentage of incorporated radioactivity (%ATI) for each fraction was calculated. The data obtained showed that the aqueous propolis extract used decreased significantly the %ATI in plasma proteins at higher concentration studied. Results suggest that at high concentration the constituents of this extract could alter the labeling of plasma proteins competing with same binding sites of the 99mTc on the plasma proteins or acting as antioxidant compounds.

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