Santos Roberto Pereira, Barros Jaqueline Daniele Santos, Pereira Euzinete Borges, Oliveira Karla Gabriela Mota de, Brito Gabriel Sousa, Costa Fernanda Farias, Fidelis Queli Cristina, Reis Aramys Silva, Holanda Carlos Alexandre, Dutra Richard Pereira
Graduate Program in Health and Technology, Federal University of Maranhão, Imperatriz, MA, Brazil.
Bachelor's Degree in Natural Sciences, Federal University of Maranhão, Imperatriz, MA, Brazil.
J Biotechnol. 2025 Sep;405:263-274. doi: 10.1016/j.jbiotec.2025.05.018. Epub 2025 Jun 6.
This study investigates the use of Amazon red propolis for the green synthesis of antibacterial silver nanoparticles (AgNPs). A hydroalcoholic propolis extract was fractionated to yield fractions rich in phenolic compounds. High-performance liquid chromatography identified calycosin as a chemical marker, along with liquiritigenin, isoliquiritigenin, and formononetin. The propolis extract and the chloroform fraction inhibited Staphylococcus aureus growth with a bactericidal effect, while for Escherichia coli, a bacteriostatic effect was observed at concentrations below 1000 µg/mL. The AgNPs were characterized by UV-Vis spectroscopy, confirming surface plasmon resonance, and their morphology and size were analyzed using dynamic light scattering and transmission electron microscopy, with elemental composition assessed via energy-dispersive spectroscopy. X-ray diffraction and selected area electron diffraction showed the crystalline structure. Fourier-transform infrared spectra indicated that carboxyl and hydroxyl groups in flavonoids reduce silver ions and contribute to the nanoparticles' chemical stability. The nanoparticles synthesized from the propolis extract showed enhanced antibacterial potential, with efficacy against E. coli (MIC 25 µg/mL, MBC 50 µg/mL) compared to S. aureus (MIC 100 µg/mL, MBC 100 µg/mL), and demonstrated selectivity for Gram-negative bacteria over murine macrophages (CC 83.92 μg/mL). These nanoparticles exhibited maximum absorption in the UV-Vis region at 418 nm, with a spherical silver core encapsulated by compounds from propolis, hydrodynamic diameter of 252.47 ± 1.42 nm, a zeta potential of -51.80 ± 0.70 mV, and a polydispersity index of 0.218 ± 0.01, indicating high chemical stability. These findings underscore Amazon red propolis as a sustainable resource for developing selective and stable antibacterial agents.
本研究调查了亚马逊红蜂胶在抗菌银纳米颗粒（AgNPs）绿色合成中的应用。将水醇蜂胶提取物进行分馏，得到富含酚类化合物的馏分。高效液相色谱法鉴定了毛蕊异黄酮为化学标志物，同时还有甘草素、异甘草素和芒柄花素。蜂胶提取物和氯仿馏分对金黄色葡萄球菌生长有抑制作用，具有杀菌效果，而对于大肠杆菌，在浓度低于1000μg/mL时观察到抑菌作用。通过紫外可见光谱对AgNPs进行表征，确认表面等离子体共振，使用动态光散射和透射电子显微镜分析其形态和尺寸，并通过能量色散光谱评估元素组成。X射线衍射和选区电子衍射显示了晶体结构。傅里叶变换红外光谱表明，黄酮类化合物中的羧基和羟基可还原银离子，并有助于纳米颗粒的化学稳定性。由蜂胶提取物合成的纳米颗粒显示出增强的抗菌潜力，对大肠杆菌（MIC 25μg/mL，MBC 50μg/mL）的疗效优于金黄色葡萄球菌（MIC 100μg/mL，MBC 100μg/mL），并且对革兰氏阴性菌比对小鼠巨噬细胞具有选择性（CC 83.92μg/mL）。这些纳米颗粒在紫外可见区域的最大吸收波长为418nm，球形银核被蜂胶化合物包裹，流体动力学直径为252.47±1.42nm，zeta电位为-51.80±0.70mV，多分散指数为0.218±0.01，表明具有高化学稳定性。这些发现强调了亚马逊红蜂胶是开发选择性和稳定抗菌剂的可持续资源。
