RESUMO
Organic phosphoester (OPE) antioxidants are currently required due to their contribution to enhancing the quality of polymers, including polypropylene (PP). In this research, an integral methodology is presented for the efficient extraction of bis(2,4-dicumylphenyl) pentaerythritol diphosphite from industrial wastewater. Upon employing the solid-phase extraction (SPE) technique, the recovered compound is subjected to a comprehensive analysis of the recovered compound using high-performance liquid chromatography (HPLC), mass spectrometry (MS), thermal analysis (TGA), Fourier transforms infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Subsequently, purified Bis(2,4-dicumylphenyl) pentaerythritol diphosphite was evaluated as a thermo-oxidative stabilizer after incorporation into PP resins. The relative standard deviation (RSD), Error (Er), linearity (R2), and percentage (%) recovery were less than 2.6, 2.5, more significant than 0.9995, and greater than 96%, respectively, for the inter-day and intra-day tests of the chromatographic method and the SPE. Except for chloroform, which was necessary due to the solubility properties of the investigated analyte, the use of environmentally friendly solvents, such as methanol and acetonitrile, was considered during the development of this research. The OPE extracted from industrial wastewater was characterized by FTIR, UV-Vis, DSC, TGA, and MS, allowing the elucidation of the structure of Bis(2,4-dicumylphenyl) pentaerythritol diphosphite (BDPD). The recovered OPE was mixed with PP resins, allowing it to improve its thermal properties and minimize its thermo-oxidative degradation. Organophosphorus flame retardant (OPE)' concentration in wastewater is alarming, ranging from 1179.0 to 4709.6 mg L-1. These exceed toxicity thresholds for aquatic organisms, emphasizing global environmental risks. Using a validated solid-phase extraction (SPE) technique with over 94% recovery, the study addresses concerns by removing organic contaminants and supporting circular economy principles. The high economic and environmental significance of recovering BDPD underscores the need for urgent global attention and intervention.
RESUMO
Given that the use of some preservatives in cosmetics has been restricted, novel alternative preservatives are needed. The aim of this study was to characterize the physicochemical and antimicrobial properties of two polyelectrolyte complexes (EuB100 and EuB75Cl25), which were developed through hot melt extrusion (HME) using benzoic acid (BA) and Eudragit E100. Based on phase diagrams and an experimental statistical design, the solubility of the acid in the polymer and the HME conditions were established. Intermolecular interactions were evaluated through Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRPD). Release behavior was determined for the systems. Antibacterial activity and ζ-potential were determined on Escherichia coli. FTIR revealed acid-base interaction, and XPS showed that the percentages of protonated nitrogen N1s were 13.5% for EuB100 and 20.3% for EuB75Cl25. The BA released showed a non-Fickian behavior, and a satisfactory antibacterial activity against E. coli was demonstrated at pH 6.9. The complexes modified ζ-potential, destabilizing the membrane functionality of E. coli. These complexes are potential antimicrobial preservatives with a greater spectrum of action, with bactericidal activity against E. coli in a wider pH range than uncomplexed BA, even at pH 6.9.
Assuntos
Anti-Infecciosos , Ácido Benzoico , Acrilatos , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Varredura Diferencial de Calorimetria , Composição de Medicamentos , Escherichia coli , Polímeros , Solubilidade , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
El objetivo de este estudio fue describir la histología del hígado del chigüire (Hydrochoerus hydrochaeris). Para tal fin, se utilizaron 13 hígados de individuos adultos de ambos sexos, con un peso entre 33 y 50 kg de peso, los cuales fueron sacrificados en el Matadero- frigorífico de Pro-Fauna, localizado en el municipio de Iguape, estado de São Paulo y en el campus de la Universidad Federal de Viçosa, en el estado de minas Gerais, Brasil. Las muestras fueron fijadas en líquido de Bouin y en solución de formol al 10% v/v, y se procedió a realizar el procesamiento histológico de rutina. Para la visualización diferencial del tejido conjuntivo y de las fibras colágenas para la descripción general del tejido, se realizaron cortes de tejido de 4 µm, los cuales fueron coloreados posteriormente para su estudio histológico, utilizando las técnicas de coloración de hematoxilina & eosina, P.A.S. y Tricrómico de Gomori. Los resultados del estudio revelaron la presencia de un parénquima hepático y lobulillos, los cuales se encontraban próximos unos a otros, no existiendo delimitación marcada entre ellos. Los hepatocitos se encontraban agrupados en placas o hileras que se anastomosaban entre sí, y se disponían en una capa de células. Desde el punto de vista histológico, el parénquima hepático del Hydrochoerus hydrochaeris puede ser considerado como semejante en diversos aspectos, al de otros mamíferos.
The objective of the present study was to histologically describe the liver of the capybara (Hydrochoerus hydrochaeris). For that purpose, 13 livers of capybaras of both sexes, weighing between 33 and 50 kg, were used. The animals were slaughtered in the Pro-Fauna refrigerated slaughterhouse, located in Iguape, the State of São Paulo and in the campus of the Universidad Federal de Viçosa, the State of Minas Gerais, Brasil. Samples were fixed in Bouin and formalin solution (10% v/v) and a routine histological processing was made. For the differential visualization of the connective tissue and colagen fibers, and for the general description of the tissue, sections of tissues of 4 µm were made. Subsequently, tissue sections were stained with hematoxylin and eosin, P.A.S., and Gomori trichrome. The results of the study revealed the presence of a liver parenchyma and lobules, which were close to one another, without a marked delimitation among them. The hepatocytes were grouped in plates or rows which anastomosed with each other and were arranged in a layer of cells. From the histological standpoint, the liver parenchyma of the Hydrochoerus hydrochaeris can be considered similar in various aspects, to that of other mammals.