Antimicrobial and scavenging potential of green synthesized silver/manganese bimetallic nanoparticles using Euphorbia cactus extract

Abstract

The fabrication of novel nanomedicines in the pursuit of alternative therapeutics has increasingly embraced eco-friendly strategies. This study reports the phytogenic synthesis of bimetallic silver-manganese nanoparticles (Ag/MnNPs) through bio-reduction using non-toxic extract from aerial part of Euphorbia cactus as a sustainable and environmentally benign reducing and stabilizing agent. Advanced spectroscopic and microscopic characterization techniques were applied to elucidate the physico-chemical features of green synthesized Euphorbia cactus -mediated Ag/MnNPs (EC-Ag/MnNPs). The formed EC-Ag/MnNPs were predominantly spherical and uniform, with an average size of 18.32 nm. Fourier transform infrared spectroscopy (FTIR) analysis revealed the existence of multiple functional groups, indicating the involvement of Euphorbia cactus phytoconstituents in the synthesis, reduction and stabilization of EC-Ag/MnNPS. The energy-dispersive X-ray (EDX) estimation confirmed the elemental composition, showing 43.62% of silver and 18.71% manganese content. Both biogenic bimetallic EC-Ag/MnNPs and Euphorbia cactus (EC) extract exhibited excellent antimicrobial and scavenging potential. The bimetallic EC-Ag/MnNPs exerted superior antibacterial efficacy, with maximum inhibition zones of 38.15 ± 0.32 mm against Escherichia coli and 36.81 ± 0.51 mm against Salmonella Typhi . EC-Ag/MnNPs also showed remarkable antifungal efficacy against Candida glabrata (35.10 ± 0.39 mm) and Candida parapsilosis (33.82 ± 0.97 mm). Additionally, the biosynthesized EC-Ag/MnNPs showed strong, dose-dependent antioxidant activity, achieving a maximum scavenging efficiency of 96.12% at a concentration of 80 µg/mL. The results demonstrated significant antimicrobial and antioxidant properties of green-synthesized EC-Ag/MnNPs, underscoring their potential application in antimicrobial formulations and enhancement of medical device functionality.