Navegando por Autor "Morais, Eduardo Beraldo de"

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    Exploring the Dipteryx alata fruit endocarp as a novel source for the synthesis of silver nanoparticles: antibacterial and photocatalytic insights for water purification
    (IWA publishing) Morais, Eduardo Beraldo de; Nascimento, Marielle Xavier; Vasconcelos, Leonardo Gomes de; Golin, Rossean; Lopes, Paulo Renato Matos; Ambrosio, Jéssica Aparecida Ribeiro; Simioni, Andreza Ribeiro
    A simple, rapid, and non-toxic method was developed to synthesize silver nanoparticles (AgNPs) using an aqueous extract from the endocarp of Dipteryx alata fruit (DAE), a tree species native to the Brazilian Cerrado. The synthesis involved mixing DAE with a solution of AgNO3 (2 mM) at room temperature. AgNPs synthesis was confirmed through detection of the surface plasmon resonance band at 421 nm. Characterization revealed spherical AgNPs with an average diameter of 137.5 + 59.3 nm. FTIR analysis confirmed phytochemical involvement in AgNPs reduction and capping, while XRD analysis indicated their crystalline nature with a face-centered cubic structure. AgNPs exhibited antibacter- ial activity against Escherichia coli and Enterococcus faecalis, with zones of inhibition ranging from 10–4 mm for E. coli and 9–13 mm for E. faecalis, indicating sensitivity to AgNPs. Photocatalytic activity against rhodamine B (RhB) resulted in 99.3% removal in 180 min, with a degradation rate constant of 0.034 L mg 1 min 1 based on pseudo second-order kinetics. Phytotoxicity studies confirmed the non-toxic nature of degraded RhB products on Cucumis sativus. These findings highlight the potential of AgNPs from DAE extract in antibacterial and dye remediation applications.
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    Green synthesis of iron nanoparticles from the baru (Dipteryx alata) endocarp extract for the efficient removal of rhodamine B and caffeine from water through the heterogeneous Fenton process
    (IWA) Corrêa, Cassiano Ricardo Reinehr; Siqueira, Adriano Buzutti de; Lopes, Paulo Renato Matos; Ambrosio, Jéssica Aparecida Ribeiro; Simioni, Andreza Ribeiro; Vasconcelos, Leonardo Gomes de; Morais, Eduardo Beraldo de
    This study presents the first-time synthesis of iron nanoparticles (FeNPs) using an aqueous extract from the baru fruit endocarp (Dipteryx alata). Characterization through scanning electron microscopy and dynamic light scattering revealed spherical shapes with an average diameter of 419.2 nm. Fourier transform infrared spectroscopy identified phytochemicals from the baru fruit extract, acting as both reducing and stabilizing agents. X-ray diffraction confirmed the amorphous nature of the FeNPs. The Fenton-like catalytic efficiency of FeNPs was investigated for degrading rhodamine B (RhB) and caffeine. The impact of crucial parameters such as pH, H2O2 dosage, nanoparticles concentration, and temperature on the degradation process was assessed. At pH 3.0, with 1.0 g L−1 of FeNPs, 1% H2O2, and 45 °C, RhB and caffeine degradation reached 99.14 and 92.01%, respectively. The catalytic reaction kinetics followed a pseudo-first-order model for caffeine and a pseudo-second-order model for RhB. Phytotoxicity studies on Cucumis sativus confirmed the non-toxic nature of the degraded products of RhB and caffeine. These findings highlight the potential of FeNPs synthesized from the baru endocarp extract as a catalyst for removing organic pollutants, suggesting promising applications in environmental remediation and related fields.