Biosynthesis of silver capped magnesium oxide nanocomposite using Olea cuspidata leaf extract and their photocatalytic, antioxidant and antibacterial activity

Abstract

Green chemistry is a modern area of research which covers synthesis of nanomaterials through useful, environmentally, economically friendly techniques and their use in different fields. The synthesis involves the formation of bimetallic nanomaterials to enhance their synergistic relationship and achieve special modulated properties. That's why bimetallic nanomaterials are extremely important and gaining interest among researchers in the field of medicinal chemistry for the treatment of various diseases. In this particular study, bimetallic nanoparticles synthesis was done by reduction procedure using leaf extract of Olea cuspidata. The phytochemicals in leaf extract act as stabilizing and capping agent in reduction of precursor's salts. The characterization of green synthesized Ag@MgO nanocomposite was done through several analytical techniques such as ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), High resolution transmission electron microscope (HRTEM) and Zeta potential. To explore the biological potential of synthesized nanocomposite, antibacterial activities against gram negative (Escherichia coli) bacteria and gram positive (Staphylococcus aureus) has been evaluated. The photocatalytic activity in contrary to methylene blue (MB) decomposition was seen efficiently. Moreover, the antioxidant nature of green synthesized Ag@MgO nanocomposite was analyzed by destabilizing and scavenging maximum percentage (93 %) of dangerous and harmful 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical. The best and surprising results provided the information for the presence of essential and vital components in Olea Cuspidata in the form of organic acids (Citrus Acid) aids in stabilizing the entire structure with enhanced properties. Up to the best of our knowledge, the facts and results obtained regarding the structure of Ag@MgO nanocomposite clearly illustrates the uniqueness of green chemistry and also its role in future developing multifunctional nanoparticles in the field of nanobiotechnology.

Keywords: Ag@MgO nanocomposites; Cytotoxicity; Olea cuspidata; Photodegradation of methylene blue.