Copper nanoparticles stabilized with cashew gum: Antimicrobial activity and cytotoxicity against 4T1 mouse mammary tumor cell line

Abstract

Copper nanoparticles stabilized with cashew (CG-CuNPs) were synthesized by reduction reaction using ascorbic acid and sodium borohydride, using the cashew gum (CG) as a natural polymer stabilizer. Dynamic light scattering, atomic force microscopy, Fourier-transform infrared spectroscopy, UV-Vis spectrophotometry, and x-ray diffraction were used to characterize the nanoparticles (CG-CuNPs), and copper was quantified by electrochemical measurement. The UV-vis spectra of the CG-CuNPs confirmed the formation of nanoparticles by appearance of a surface plasmon band at 580 nm after 24 h of reaction. The Fourier-transform infrared spectrum of CG-CuNPs showed the peak at 1704 cm−1 from cashew gum, confirming the presence of the gum in the nanoparticles. The average size of CG-CuNPs by dynamic light scattering and atomic force microscopy was around 10 nm, indicating small, approximately spherical particles. Antimicrobial assays showed that CG-CuNPs had activity against Staphylococcus aureus ATCC 29213 with a minimal inhibitory concentration of 0.64 mM. The cytotoxicity assay on BALB/c murine macrophages showed lower cytotoxic effects for CG-CuNPs than CuSO4·5H2O. Viability cell assays for CG-CuNPs at (0.250 mM) inhibited by 70% the growth of 4T1 LUC (4T1 mouse mammary tumor cell line) and NIH 3T3 cells (murine fibroblast cells) over a 24-h period. Therefore, CG-CuNPs can be used as an antimicrobial agent with lower cytotoxic effects than the CuSO4·5H2O precursor.

Antimicrobial Nano-Agents: The Copper Age

“…It was above 80% even up to 1000 μg/mL and definitely higher compared to copper sulfate, suggesting the importance of the nanomaterial composition. Similar results were obtained with cashew gum-stabilized CuNPs on murine macrophages and murine fibroblast cells and with CuS hydrogels after 48 h on mouse embryonic fibroblasts, where the proliferation results were even more promoted …”

“…45 Similarly, in vitro inhibition of bacteria growth has been observed with CuNPs prepared in the presence of Heliconia psittacorum 13 or fermented fenugreek (Trigonella foenum) powder under the action of Pleurotus ostreatus or stabilized with cashew gum. 38,46 The last work compares the action of copper ions released by copper sulfate in alginate matrix and CuNPs with ciprofloaxacin in a "zone of inhibition" test. Interestingly, the copper ion sample does not create any growth inhibition against K. pneumoniae, S. aureus, and Candida albicans.…”

“…53 It was above 80% even up to 1000 μg/mL and definitely higher compared to copper sulfate, suggesting the importance of the nanomaterial composition. Similar results were obtained with cashew gumstabilized CuNPs on murine macrophages and murine fibroblast cells 46 and with CuS hydrogels after 48 h on mouse embryonic fibroblasts, where the proliferation results were even more promoted. 90 A prior evaluation of the impact of CuNPs on the functionality of organs and the description of their biokinetics is pivotal for the translation of nanomaterials to the clinical practice.…”

Ações terapêuticas do exsudato (goma) do cajueiro: uma revisão

“…Após a aplicação dos critérios de inclusão e exclusão (Figura 1), 24 artigos foram eleitos para serem lidos na íntegra. Embora os mecanismos de ação não estejam totalmente elucidados, os estudos sugerem que a ação antibacteriana da goma do cajueiro, tanto em bactérias Gram-positivas quanto em bactérias Gram-negativas, pode ocorrer por diferentes mecanismos, entre eles está a capacidade de ligação da GC às moléculas de peptidoglicanos presente na parede celular das bactérias, aumentando sua permeabilidade e consequentemente ocasionando seu rompimento; alteração e/ou inativação de proteínas estruturais de membrana afetando seu potencial eletroquímico; geração de espécies reativas de oxigênio (ROS) e radicais livres que causam danos ao material genético bacteriano, modulação das vias de transdução das bactérias; e inativação da cadeia respiratória bacteriana (Campos et al, 2012;Queleme et al, 2013;Queleme et al, 2017;Lustosa et al, 2017;Amorim et al, 2019;Araruna et al, 2020) GC ainda são escassas na literatura científica e sugerem que novos estudos são necessários para avaliar o possível potencial antimicrobiano frente às diferentes espécies de fungos.…”