Eco-Friendly Zinc Oxide Nanoparticles from Trachystemon orientalis L.: Examination of Their Antibacterial, Anti-Alzheimer, and Antidiabetic Potentials.

INTRODUCTION: This study aimed to biogenically synthesize and characterize Zinc Oxide Nanoparticles (ZnONPs) using the Trachystemon orientalis L. plant extract. It also aimed to evaluate the antibacterial potential and metabolic enzyme-inhibitory activities of these green-synthesized nanoparticles for medical and industrial applications. METHODS: Nanoparticles were synthesized using a green chemistry approach, where the plant extract acted as a reducing agent for zinc ions. The structural and morphological properties of ZnONPs were analyzed using X-ray Diffraction (XRD), Fourier-transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy-dispersive X-ray Spectroscopy (EDX). Antibacterial efficacy was evaluated by determining the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) against Staphylococcus aureus and Escherichia coli. Additionally, the inhibitory effects on α-glycosidase, Acetylcholinesterase (AChE), and Butyrylcholinesterase (BChE) enzymes were investigated to determine the inhibition constant (Ki) values. All experiments were conducted in triplicate, and the results are expressed as mean ± standard deviation. RESULTS: XRD analysis confirmed the crystalline metallic structure of ZnONPs, SEM imaging revealed a predominantly rod-shaped morphology, and EDX analysis verified that the elemental composition was predominantly zinc, consistent with ZnO nanoparticle formation. FTIR spectra confirmed the successful capping of the nanoparticles by plant-derived bioactive compounds. Antibacterial assays showed significant activity, with MIC values of 125 μg/mL for S. aureus and 250 μg/mL for E. coli. Enzyme inhibition studies yielded potent results, with Ki values of 47.10 ± 3.72 μM for α-glycosidase, 3.55 ± 0.43 μM for BChE, and 15.47 ± 1.24 μM for AChE, all of which outperformed standard inhibitors such as tacrine and acarbose. DISCUSSION: The results demonstrate that the biogenic synthesis of ZnONPs using T. orientalis is an effective and eco-friendly method for producing nanoparticles with high biological activity. The superior enzyme inhibition and antibacterial performance compared to conventional standards suggest that these nanoparticles possess unique surface properties owing to the plant-derived organic shell, enhancing their interaction with biological targets. CONCLUSION: This study successfully synthesized rod-shaped zinc oxide nanoparticles with significant antimicrobial and enzyme-inhibitory properties. These findings highlight the potential of biogenically synthesized ZnONPs as multifunctional agents in the development of new therapeutic strategies for managing bacterial infections and metabolic disorders.