Akademik Veri Yönetim Sistemi
BioNanoScience, cilt.16, sa.5, 2026 (ESCI, Scopus)
In this study, silver nanoparticles (AgNPs) were biologically synthesized from the cell-free supernatant of Ureibacillus thermosphaericus DSM 10633T. Optimization studies resulted in a 3.5-fold increase in AgNP production, yielding 53 mg of dry nanoparticles from a 250 mL culture. UV-Vis spectroscopy confirmed the presence of AgNPs through a characteristic surface plasmon resonance at 412 nm, while Fourier transform infrared (FT-IR) spectroscopy identified biomolecules responsible for the reduction and stabilization of the nanoparticles. Transmission electron microscopy (TEM) revealed spherical nanoparticles ranging from 9 to 32.5 nm in size. Energy-dispersive X-ray spectroscopy (EDS) demonstrated the predominancy of silver that stabilized by organic components, supporting the successful biosynthesis and surface functionalization. The biosynthesized AgNPs showed broad-spectrum antimicrobial activity against sixteen clinical pathogens, and sub-MIC concentrations significantly inhibited biofilm formation in all tested strains. The cytotoxicity evaluation using the MTT assay showed selective effects, with low toxicity for healthy cell lines (L929, HDF, HaCaT), and markedly lower IC50 values (9–10 µg/mL) for cancer cell lines (MCF-7, HT-29, A549). Additionally, a combined treatment of AgNPs and the chemotherapeutic agent 5-fluorouracil (5-FU) revealed synergistic interactions in MCF-7 cells at AgNPs:5-FU ratios of 1:2 (combination index = 0.519) and 1:4 (CI = 0.688). These findings highlight the potential of DSM 10633T-dervied AgNPs as effective antimicrobial and antibiofilm agents with promising biomedical applications. The observed cell line-specific synergy with 5-FU in MCF-7 cells suggests the potential for AgNP-based combination therapies in breast cancer models. Future studies should explore the in vivo efficacy, biocompatibility and therapeutic safety of these nanoparticles to advance their translation to clinical applications.