Olea Europaea Mediated Bioengineered Biocompatible Gold Nanoparticles for Antimicrobial, Cytotoxic Applications, and Molecular Docking Study

The objective of this research work is to demonstrate the ecologically friendly fabrication of gold nanoparticles (OL-Au NAPs) using the biomolecules of Olea europaea leaf extract. Several spectroscopic approaches were utilized to analyze green fabricated OL-Au NAPs efficiently. OL-Au NAPs were investigated against two different bacteriological strains for antibacterial and biofilm inhibition efficacy. The MTT technique was used to determine the cytotoxic activity against MCF-7 cancerous cells, which was expressed as a percentage of viable cells. The biocompatibility of the synthesized NAPs was evaluated further by incubating them for 24 h with hMSC and 293T cell lines. The results indicated that synthesized OL-Au NAPs effectively suppressed proliferation and biofilm formation in all tested bacteria. Their antibacterial activity was statistically equivalent to that of standard antibiotics (p > 0.05). In silico molecular docking studies confirmed that OL-Au NAPs can also bind and inhibit important S. aureus proteins involved in the cell wall and fatty acid biosynthesis pathways. Moreover, they outperformed plant leaf extract and CH-Au NAPs in terms of cytotoxic effects on MCF-7 cancerous cells. Green fabricated OL-Au NAPs seemed more biocompatible with 293T and hMSC cells than CH-Au NAPs. The promising biological properties of the OL-Au NAPs may be a result of the NAPs' properties interacting with the adsorbed bioactive molecules from plant leaf extract. As a consequence of this study, synthesized OL-Au NAPs may be a potential choice for their numerous pharmacological and nutritional properties. This discovery will also open the road for the creation of nontoxic nanomaterials with extra biologic properties obtained from plants.