Biogenically produced Gold nanoparticles containing a Fluoroquinolone molecule from the cell-free extract of E. hormaechei soil isolates with anti-bacterial and anti-cancer properties

Nanotechnology’s potential for therapies, drug delivery, and environmental applications has sparked much interest in the bioscience and pharmaceutical industries. The present study utilizes the possibility of generating metal nanoparticles (gold) using biological molecules, i.e., molecules from the cell-free supernatant of a soil isolate of E. hormaechei strain KDY2. FTIR, XRD, SEM, and UV–Vis spectroscopy were used to analyze the biosynthesized AuNPs. XRD patterns and UV–Vis spectra verified AuNP production. The SEM images showed the spherical shape of the NPs with a size of less than 100 nm, and the FTIR provided details on the capping molecules on the KDY2 NPs such as proteins, amino acids, and a fluoro compound. Additionally, cytotoxic, antifungal, antibacterial, and antioxidant tests were performed on the produced NPs. The KDY2 NPs inhibited the growth of both Gram-positive and Gram-negative bacteria. They showed considerable cytotoxicity in the human breast cancer cell line MCF-7 with an IC50 value of 79.50 ± 2.12 µg/ml, but no cytotoxicity in normal cell lines. The MCF-7 cell line was also subjected to cell cycle analysis, mitochondrial membrane potential tests, PS externalization, clonogenic, trypan blue dye exclusion, and microscopy. The western blotting analysis provided evidence for the cleavage of PARP protein indicating the onset of apoptosis in the KDY 2 NP treated MCF-7 cells. They all demonstrated that KDY2 NPs induced apoptosis in MCF-7 cells. KDY2 NPs were subjected to QTOF-LCMS/MS analysis to identify their active metabolites. The findings revealed the presence of a molecule that is exactly like Moxifloxacin and norfloxacin, pointing to the mechanism underlying the antibacterial and anti-cancer properties of the NPs. KDY2-Au-NPs may be considered a secure and potent nanoparticle formulation for antimicrobial and anti-cancer uses. With its exceptional anti-cancer characteristics, our in vitro study is the first to report on the biogenic creation of Gold nanoparticles capped with Norfloxacin utilizing E. hormaechei culture supernatant.