Valorization of seasonal waste Ficus rumphii leaves for green synthesis of mono and bimetallic nanoparticles: Characterization and their biological applications

Nanotechnology has emerged as a rapidly advancing field with transformative potential across various applications. The valorization of seasonally shed Ficus rumphii leaves, an abundant and underutilized biomass waste, was explored as a sustainable resource for the green synthesis of biologically active nanoparticles. Zinc (Zn), copper (Cu) mono-metallic and Zn-Cu bimetallic nanoparticles were synthesized using leaves extract of Ficus rumphii, which acted as both a reducing and stabilizing agent. The synthesized nanoparticles were characterized using UV-Vis spectroscopy, XRD, FESEM and EDX. Morphological analysis revealed rod shaped (Zn), irregular shaped (Cu) and mixed (Zn-Cu) structures, with crystallite sizes of 34.97 nm (Zn), 63.68 nm (Cu) and 29.22 nm (Zn–Cu). The bimetallic nanoparticles demonstrated superior biological efficacy, displaying DPPH scavenging IC₅₀ of 268.68 ± 0.23 µg/mL, α-amylase inhibition IC₅₀ of 376.71 ± 0.12 µg/mL and BSLA assay IC₅₀ of 61.43 ± 0.11 µg/mL, compared to their monometallic ones. Anti-microbial screening further showed a maximum inhibition zone of 10.21 ± 0.6 mm against P. aeruginosa. This study underscores the potential of waste biomass valorization through the green synthesis of metal nanoparticles using seasonal Ficus rumphii leaves, providing a sustainable pathway for producing environmentally friendly and biologically potent nanomaterials with promising applications in healthcare and biotechnology.