ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Characterization and antifungal potential of green-synthesized copper nanoparticles using waste leaf biomass

Yathin Puchery Yadava, Vishnu Raju, Anish Mavila Chathoth, Anoop Elaveettil Vasu, Reshmy Vijayaraghavan, and Aneesh Kunnapillil Surendran

Department of Forest Products and Utilization, College of Forestry, Kerala Agricultural University, Thrissur, India

E-mail: vishnu.r@kau.in

Received: 20 September 2024  Accepted: 6 May 2025

Abstract:

The synthesis of metal nanoparticles is of great interest among the research community due to their versatile physical, chemical, and antimicrobial properties and myriads of applications. Researchers across the world employ various protocols to synthesize metallic nanoparticles. However, the synthesis of nanoparticles using biomaterials, i.e., green synthesis, has advantages over conventional methods because they use toxic reagents and produce harmful byproducts. In this study, plant leaf extracts rich in flavonoids, tannins, glycosides, and alkaloids from four different species, including teak (Tectona grandis), neem (Azadirachta indica), lantana (Lantana camara), and senna (Senna spectabilis), were used to synthesize copper oxide nanoparticles (CuONPs) from a 0.1 M copper sulfate pentahydrate (CuSO₄.5 H₂O) solution. Plant extracts act as reducing, stabilizing, and capping agents simultaneously. Characterization via UV‒Vis spectroscopy, field emission scanning electron microscope (FE-SEM), energy-dispersive X-ray spectroscopy (EDXS), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyzer (TGA), and X-ray diffraction (XRD) as well as yield analysis was performed for the green-synthesized CuONPs. The maximum yield was obtained from teak leaf extract followed by senna, lantana, and neem. FE-SEM images confirmed the nanoscale dimensions and shape of the CuONPs, with particles synthesized from all four extracts measuring less than 100 nm in size. The presence of CuONPs was also confirmed from the UV‒Vis spectra which showed a characteristic peak between 300 and 350 nm. The CuONPs were further analyzed through EDXS, FTIR, XRD, and TGA which showed characteristic peak regions in the graph. The antifungal potential of CuONPs was evaluated against Corynespora cassiicola using the poison food technique at concentrations of 100 ppm, 500 ppm, and 1000 ppm. CuONPs exhibited significant inhibition of fungal growth in a dose-dependent manner, with inhibition rates of 50%, 62.5%, and 75%, respectively. Overall, this study provides an insight into the importance of selecting suitable plant extracts for the production of CuONPs in a cost-effective and environmentally friendly way.

Graphical abstract

Keywords: Nanomaterial; Nanoparticle Synthesis; Natural Product Synthesis; Natural Products; Nanoparticles; Plant Materials; Antifungal; Characterization; Green synthesis; Nanoparticles; Plant extract

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04124-2

Chemical Papers 79 (8) 5261–5275 (2025)