Abstract
•A green synthesis of Ag/NiO nanocomposite using leaf extract of Uncaria rhynchophylla as reducing and capping agent.•Ag/NiO nanocomposite exhibited remarkable antimicrobial activity against multidrug resistant bacteria.•Ag/NiO nanocomposite have significant antioxidant activity against DPPH.•Τοxicity against red blood cells.•Ag/NiO nanocomposite have efficient photocatalytic activity in terms of photocatalytic degradation of methylene blue.
The increase of microbial resistance poses threats to human health. Therefore, efficient treatment of microbial resistance is a global challenge.. During this study, the Ag/NiO nanocomposite was fabricated via simple and ecofriendly method, using Uncaria rhynchophylla extract as a reducing and capping agent to avoid the aggregation of as synthesized nanomaterials. Here, a range of characterization techniques were employed to characterize the sample which includes UV–vis spectroscopy, X-ray diffraction, FTIR spectroscopy, electron diffraction spectroscopy (EDX), scanning electron microscopy (SEM). Furthermore, the resultant nanocomposite demonstrated an efficient ability for the inhibition of both gram-positive and gram negative pathogenic multidrug resistant bacteria. Additionally, the Ag/NiO nanocomposite showed a durable antioxidant effect against DPPH that could still reach 63% at very low concentration, i.e. 0.5 mg/mL. Interestingly, the synthesized nanocomposite is efficient for the production of reactive oxygen species (ROS) and shows no hemolytic activity. Likewise, the Ag/NiO nanocomposite displayed excellent photocatalytic activity to degrade 85% methylene blue (MB) by 4 mg/25 mL and could be used for waste water treatment. It is believed that synthesized nanostructure with desirable morphology and preparation simplicity can be promising material for antimicrobial, antioxidant and catalytic applications.