The present work presented a synthesis of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) using the aqueous extract of waste banana stem (WBS), Musa paradisiaca Linn. The reduction and formation of MNPs have been characterized by several analysis techniques such as X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM). The techniques showed that average particle size of WBS-AgNPs and WBS-AuNPs in crystalline nature was in ranges of 7–13 nm and 11–14 nm, respectively. The synthesized nanoparticles were used to evaluate antibacterial activity and catalysis. The WBS-AgNPs showed strong antibacterial activity against B. subtilis and E. coli. The largest zone of inhibition against B. subtilis (14.2 mm) and E. coli (9.3 mm) was found at concentrations of 4.0 ppm and 2.0 ppm, respectively. The excellent catalytic application of both the nanoparticles for the reduction of 4-nitrophenol was confirmed via study on their kinetics. The normalized kinetic constants (k_nor) of WBS-AgNPs and WBS-AuNPs were found to be 1.72 × 10^–3 s⁻¹ mg⁻¹ and 2.45 × 10^–3 s⁻¹ mg⁻¹, respectively.

本工作介绍了使用废香蕉茎（WBS），Musa paradisiaca Linn的水提物合成银纳米颗粒（AgNPs）和金纳米颗粒（AuNPs）的方法。MNP的还原和形成已通过多种分析技术进行了表征，例如X射线衍射（XRD），傅立叶透射红外光谱（FTIR），扫描电子显微镜（SEM），透射电子显微镜（TEM）。该技术表明，WBS-AgNPs和WBS-AuNPs的结晶性平均粒径分别在7–13 nm和11–14 nm范围内。合成的纳米颗粒用于评估抗菌活性和催化作用。WBS-AgNPs对枯草芽孢杆菌和大肠杆菌具有很强的抗菌活性。发现对枯草芽孢杆菌（14.2 mm）和大肠杆菌（9.3 mm）的最大抑制区分别在4.0 ppm和2.0 ppm的浓度下。通过研究其动力学，证实了这两种纳米颗粒在还原4-硝基苯酚方面的优异催化应用。发现WBS-AgNPs和WBS-AuNPs的归一化动力学常数（k _nor）分别为1.72×10 ^–3  s ^-1  mg ^-1和2.45×10 ^–3  s ^-1  mg ^-1。