Myco-assisted zinc oxide nanoparticles by Aspergillus sp. SA18: Chemical profiling, antimicrobial, anticancer, and computational insights into GyrA and GyrB inhibition with ADME physicochemical properties.

This study aimed to biosynthesize zinc oxide nanoparticles (ZnONPs) using a marine-derived Aspergillus sp. SA18 fungal extract and assess their antimicrobial and anticancer properties. ZnONPs were characterized by UV-Vis. spectroscopy, FTIR, XRD, TEM, SEM, and zeta potential analyses. Characterization approved successful nanoparticle synthesis, with a crystalline structure and an average particle size of 75 nm based on XRD analysis, while TEM and SEM exposed polydisperse spherical particles ranging from 80 to 96 nm. The synthesized ZnONPs showed a zeta potential of -21.03 mV, demonstrating good colloidal stability. Antimicrobial test demonstrated prominent activity, with the fungal extract displaying the highest inhibition zones against Pseudomonas aeruginosa and Candida albicans (16 mm each). Cytotoxicity assessment disclosed strong anticancer activity of the fungal extract against MCF-7 and HepG2 cell lines, with IC50 values of 9.75 ± 0.7 and 22.81 ± 1.7 μM, respectively, while ZnONPs displayed IC50 values of 46.11 ± 2.7 and 74.96 ± 3.8 μM against the same cell lines. Chemical profiling identified 48 metabolites, including flavonoids and phenolic acids, which may contribute to the observed bioactivities. Molecular docking showed strong binding affinities of xanthohumol toward E. coli GyrB (docking score = -8.47 kcal/mol) and herbacetin toward c-Src kinase (docking score = -8.81 kcal/mol), supported by molecular dynamics simulations and favorable ADME properties. These findings prove that Aspergillus sp. SA18-mediated ZnONPs possess auspicious antimicrobial and anticancer potential and highlight this marine fungal isolate as an efficient nanofactory for biomedical applications.