Eco-Friendly Synthesis of Biologically Active ZnO Nanoparticles from Ouret Lanata

Abstract

Green nano synthesis refers to the eco-friendly production of nanoparticles using biological resources instead of hazardous chemicals and energy-intensive processes. This approach follows the principles of green chemistry by reducing toxic reagents, minimizing waste generation, and lowering environmental impact. Green synthesis has gained significant attention due to increasing concerns about the safety and sustainability of conventional physical and chemical nanoparticle synthesis methods. Zinc oxide (ZnO) nanoparticles were successfully synthesized using an eco-friendly green synthesis method with Ouret lanata leaf extract as a natural reducing and stabilizing agent. The synthesized nanoparticles were characterized using UV–Visible spectroscopy, FTIR, XRD, and SEM to study their optical, structural, and morphological properties. UV–Visible analysis showed strong absorption in the UV region, confirming the formation of ZnO nanoparticles. FTIR spectra revealed characteristic Zn–O stretching vibrations along with plant-derived functional groups responsible for stabilization. XRD analysis confirmed the crystalline hexagonal wurtzite structure of ZnO nanoparticles with high purity. SEM images showed nearly spherical to irregular-shaped nanoparticles with slight agglomeration. The biological activities of the ZnO nanoparticles were evaluated through antioxidant and antibacterial assays. The nanoparticles exhibited concentration-dependent antioxidant activity and significant antibacterial activity against Staphylococcus aureus and Escherichia coli. These findings suggest that green-synthesized ZnO nanoparticles possess promising biological properties and have potential applications in biomedical and pharmaceutical fields.

Introduction

The text focuses on the green synthesis of zinc oxide (ZnO) nanoparticles using Ouret lanata leaf extract and the evaluation of their structural, optical, and biological properties. ZnO nanoparticles are widely valued due to their wide band gap, chemical stability, non-toxicity, and cost-effectiveness, making them suitable for applications in photocatalysis, corrosion inhibition, antimicrobial treatments, sensors, cosmetics, and biomedicine. Conventional synthesis methods, however, often involve toxic chemicals and high energy consumption, prompting the shift toward eco-friendly green synthesis approaches.

In this study, plant-mediated green synthesis is adopted as a sustainable, low-cost, and scalable alternative. Phytochemicals present in Ouret lanata leaves act as natural reducing, stabilizing, and capping agents, enabling the formation of ZnO nanoparticles while controlling their size and morphology. The synthesized nanoparticles were characterized using UV–Visible spectroscopy, FTIR, XRD, and SEM, and their antioxidant and antibacterial activities were evaluated.

UV–Visible analysis confirmed the nanoscale nature of ZnO through strong absorption in the UV region. FTIR results identified Zn–O stretching along with organic functional groups, indicating effective capping by plant biomolecules. XRD analysis revealed that the nanoparticles possess a highly crystalline hexagonal wurtzite structure with no detectable impurities, while SEM images showed nearly spherical to irregular particles with moderate agglomeration and rough, porous surfaces—features beneficial for biological and catalytic applications.

Biological activity studies demonstrated that the green-synthesized ZnO nanoparticles exhibit notable antioxidant activity (via DPPH assay) and effective antibacterial activity against Staphylococcus aureus and Escherichia coli. These results highlight the enhanced functionality imparted by bioactive surface compounds from the plant extract.

Overall, the study confirms that green synthesis using Ouret lanata is an efficient, sustainable, and environmentally benign method for producing ZnO nanoparticles with promising structural integrity and biological performance, making them suitable for future applications in biomedical, antimicrobial, and eco-friendly nanomaterial development.

Conclusion

In this study, ZNPs was synthesized by Ouret lanata leaves aqueous extract using zinc nitrate precursor.UV Visible spectrum showed a distinct peak around 290 nm, which is specific for ZNPs. The XRD results confirmed the efficiency of the synthesis process, evidencing the production of single crystalline ZNPs with hexagonal wurtzite structure. The average size of ZNPs synthesized by zinc nitrate was found to be 23.4 nm, exhibiting bullets and spherical like structures, respectively which were confirmed by XRD and SEM analyses. FT-IR studies clearly showed the formation of ZnO and indicated that the plant extract contains various phytochemicals, which work as capping and stabilizing agent for the synthesized ZNPs. The comparable or superior performance of ZnOL relative to the standard antibiotic highlights its potential as an effective antimicrobial agent, supporting its possible application in biomedical and pharmaceutical fields. From the analyses of results, it is clear that the precursor played a vital role in surface morphology and structure of ZNPs. Our results confirm the potential of Ouret lanata for the synthesis of ZNPs in a simple, fast and ecofriendly way.

References

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Copyright © 2026 Poornima N., Dr. K. Anbarasi. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.