Synthesis of gold nanoparticles using novel Eucalyptus tereticornis and their in-vitro antibacterial, antioxidant and anticancer studies

Kiran M S, Virupaxappa S Betageri, Rajith Kumar C R, Vinay S P and Latha M S

Abstract

Development of biologically inspired experimental procedures for synthesis of nanoparticles (NPs) is an important branch of nanotechnology. Synthesis of NPs which are nontoxic, eco-friendly, inexpensive and having potential medicinal properties is challenging. In present study, gold NPs were produced from Eucalyptus tereticornis leaf extract (Et-AuNPs). The Et-AuNPs were confirmed using UV–Vis absorption study which shows surface plasmon resonance peak at 569 nm. Various characteristics of Et-AuNPs were demonstrated by characterisation techniques such as scanning electron microscopy, transmission electron microscopy, x-ray diffraction and energy dispersive spectroscopy. It is found that prepared Et-AuNPs are well dispersed and spherical in shape. Significant anticancer effect on MCF-7 cell lines was observed in dose-dependent manner having IC₅₀ value of 52.0 μg ml⁻¹. Further antibacterial studies were carried out by disc-diffusion method, which revealed potential antibacterial activity of Et-AuNPs against pathogenic bacterial strains. Et-AuNPs also exhibited promising free radical scavenging efficiency performed by DPPH assay with IC₅₀ values of 62.6 μg ml⁻¹. The results suggest that green synthesised AuNPs can be exploited for clinical as well as pharmaceutical activities using nanomedicine approach in near future.