Biosynthesis of Hierochloe odorata Mediated Silver-Copper-Aluminum Trimetallic Nanoparticles and Evaluation of Its Antimicrobial Activities

Abstract

Due to erroneous usage of antibiotics, numerous infectious agents have become resistant to them and as such there has been a surge in multi-drug-resistant bacteria. This in turn has posed a grave danger to living things and the worldwide economic development. Inasmuch as different approaches are currently being used to alleviate these problems, however, majority of these approaches have some drawbacks such as being expensive, less efficient and the possibility of bringing back contaminants to the environment. Studies have shown that nanoparticles which possess large surface-area-to-volume ratio and efficient catalytic and antimicrobial characteristics, have found application as antimicrobial agents. Furthermore, the synergistic effect of trimetallic nanoparticles has also increased its efficacy as an antimicrobial agent.  In this work, silver-copper-aluminum nanoparticles (Ag-Cu-Al NPs) was efficiently biosynthesized using aqueous leaves extract of Hierochloe odorata at room temperature. The primary validation of the biosynthesized Ag-Cu-Al NPs was by an obvious color shift from grey to olive green in the wake of adding of the aqueous leaves extract to the trimetallic salt solution of silver nitrate, copper chloride and aluminum oxide. UV-vis spectroscopy of the Ag-Cu-Al NPs presented a distinct peak maximum at 405 nm. The plausible secondary metabolites in the leaves extract liable for bio-reduction, capping and homogeneity of the nanoparticles (NPs) were assessed using FTIR. The crystalline nature and particle size of the NPs were investigated using XRD. SEM-EDS analysis revealed the surface texture and constituent elements of the NPs. Furthermore, antimicrobial activity of Ag-Cu-Al NPs compared favorably with standard antimicrobial agent (Gentamicin and Fluconazole) used as positive control against Staphylococcus aureus, Salmonela sp. Aspergillus niger and Aspergillus flavus. The biosynthesized NPs has potential to manage multi-drug-resistant microorganisms.