Green  synthesis of nickel oxide nanoflowers from cherry straw extract and preparation of antibacterial PES ultrafiltration membrane

In this study, the biological properties of nickel oxide-substituted nanoflowers (NiO-NFs) obtained from cherry stalk were investigated. The antioxidant, DNA cleavage, antimicrobial, antibiofilm, microbial cell viability and antidiabetic properties of all compounds at different concentrations were examined. The antioxidant activity of NiO-NFs was found as 6.18% at 6.25 mg/L and as 33.03% at 100 mg/L. The DNA cleavage activity was examined at 50, 100, and 200 mg/L and it showed complete cleavage activity. NiO-NFs showed the most effective antimicrobial effects against E. faecalis and E. hirae as 16 mg/L, and against B. subtilis and S. aureus as 32 mg/L. Under appropriate conditions, E. coli cell vitality was 100% inhibited at 50 mg/L nanoparticle concentration. NiO-NFs showed their antidiabetic effect with a 42.5% inhibition of amylase enzyme at a concentration of 200 mg/L. The antibiofilm activities of NiO-NFs were showed significant antibiofilm activity. While the percentage of biofilm inhibition was 82.42% for P. aeruginosa at 50 mg/L, the antibiofilm ability was also 94.26% for S. aureus at the same concentration. In addition, NiO-NFs were integrated into the PES membrane in different amounts. NiO-NFs were characterized using energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) and Scanning Electron Microscopy (SEM). Contact angle analysis was performed on membranes synthesized with NiO-NFs. In the membrane study, protein and E-coli removal was examined in the dead-end filtration system. NiO-NFs blended PES membrane demonstrated 85% E. coli growth inhibition and 86% BSA removal efficiency for PES/NiO-NFs 2.0 wt% membrane.