02896naa a2200325 a 450000100080000000500110000800800410001902400520006010000190011224502070013126000090033852018210034765000250216865000210219365000180221470000200223270000170225270000220226970000220229170000240231370000210233770000190235870000220237770000270239970000200242670000250244670000210247170000180249277300600251021640462024-05-10       2024    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1007/s13399-023-05250-12DOI1 aLIMA, A. K. O.  aPhytosynthesis of silver nanoparticles using guarana (Paullinia cupana Kunth) leaf extract employing different routesbcharacterization and investigation of in vitro bioactivitiesh[electronic resource]  c2024  aThe optimization techniques are fundamental to guarantee the stability of any preparation process and the quality of the nanostructures synthesized under ideal circumstances. In this sense, this study evaluates the potential of guarana leaf extract (Paullinia cupana Kunth—Sapindaceae) for the green synthesis of silver nanoparticles (AgNPs) using routes that employ different equipment/energy sources (autoclave, LED, microwave, sunlight, ultrasound, and water bath). The aqueous extract was characterized by high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLCHRMS/ MS). The AgNPs were analyzed by UV/Vis spectroscopy, dynamic light scattering (DLS), zeta potential (ZP), Fourier transform infrared (FTIR), transmission electron microscopy (TEM) and their antibacterial, leishmanicidal and cytotoxic effects were evaluated in vitro. The results show the presence of phenolic acids, alkaloids, and flavonoids in the leaf extract, which was supported by the identification of their functional groups in the FTIR spectra. The AgNPs showed maximum absorption between 420 and 440 nm (UV/Vis), with a diameter below 100 nm (DLS) and 60 nm (TEM), spherical morphology and a surface charge above − 30 mV (ZP). The antibacterial test showed pronounced inhibition in the growth of Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus bacteria. The leishmanicidal activity of AgNPs on Leishmania (Leishmania) amazonensis was more pronounced than that of the drug miltefosine while low cytotoxicity was reported on RAW 264.7 macrophages. With this, this study reports the possibility of using alternative routes for the sustainable synthesis of AgNPs from Paullinia cupana extract with considerable applications against pathogenic bacteria and opportunistic parasites.  aAntibacterial plants  aAntileishmanials  aNanoparticles1 aSILVEIRA, A. P.1 aSILVA, R. C.1 aMACHADO, Y. A. A.1 aARAÚJO, A. R. de1 aARAUJO, S. S. de M.1 aVIEIRA, I. R. S.1 aARAÚJO, J. L.1 aSANTOS, L. C. dos1 aRODRIGUES, K. A. da F.1 aSILVA, S. W. da1 aRIBEIRO, J. A. de A.1 aRODRIGUES, C. M.1 aGARCIA, M. P.  tBiomass Conversion and Biorefinerygv. 14, n. 10, 2024.