Green synthesis of silver nanoparticles using Eucalyptus leucoxylon leaves extract and evaluating the antioxidant activities of extract.

This study was designed to examine the in vitro antioxidant activity of essential oil and methanol extracts of Eucalyptus leucoxylon. Furthermore, the polar fraction of the extract was used as a reducing agent for the green synthesis of silver nanoparticles (Ag NPs). Antioxidant activities of the samples were determined by using three different test systems, namely DPPH and β-carotene/linoleic acid and reducing power. The structure and composition of the prepared Ag NPs were characterised by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and UV-vis spectroscopy. Synthesised Ag NPs were almost spherical in shape with an average diameter of about ∼ 50 nm and synthesised within 120 min reaction time at room temperature.