Foeniculum Vulgare leaf extract loaded synthesis of silver nanoparticles in different volume ratios for antimicrobial and antioxidant activities: Comparative study of composition

The current world is exposed to immense classes of challenges, of which antimicrobial-caused infectious diseases have been ranked the third killer disease due to their high resistance capability. Oxidative stress is also the other problem faced by the current world. In the current study, a leaf of Foeniculum Vulgare was employed for the synthesis of silver nanoparticles (Ag NPs) within the 1:3, 1:1, and 3:1 compositions using 0.1 M of AgNO₃. The calculated average crystalline size from X-ray diffraction (XRD) was found to be 12.6, 13.7, and 21.6 nm for the 1:3, 1:1, and 3:1 volume ratios, respectively. Scanning electron microscope coupled with energy dispersive spectroscopy (SEM-EDS) analysis depicts the quasi-spherical shape with an intense Ag peak at around 3.00 eV. Transmission electron microscope coupled with high-resolution transmission microscope with surface area electron diffraction pattern (TEM-HRTEM with SAED) showed spherical shaped Ag NPs. The electronic bandgap energy was calculated as 3.1, 3.2, and 3.3 eV for the 1:1, 3:1, and 1:3 volume compositions, respectively. Ag NPs show 13.5, 12.5, and 11.0 mm zones of inhibition for the 1:3, 1:1, and 3:1 ratios, respectively. The antifungal activity was found to be 16.9, 11.2, and 10.5 mm for the 3:1, 1:3 and 1:1 ratios, respectively. Lastly, the antioxidant activity was estimated to be 42.4, 28.94, and 27.39% RSA for the 1:1, 3:1, and 1:3 volume ratios respectively. All the ratios of Ag NPs showed promised antimicrobial and antioxidant activity in the presence of 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) due to the enhanced generation of reactive oxygen species (ROS).

Graphical Abstract