Green synthesis of zinc oxide nanoparticles from fallen Aegle marmelos leaves with antioxidant, antimicrobial and antidiarrheal activities
摘要
Zinc oxide nanoparticles (ZnO NPs) were synthesized through green-approach methods using aqueous solution of fallen Aegle marmelos leaf extract. The prepared NPs were characterized using different spectroscopy techniques including Fourier Transform Infrared (FTIR), Dynamic Light Scattering (DLS), X-ray Diffraction Patterns (XRD) and electron microscopy such as Field Emission Scanning Electron Microscopy (FESEM). XRD study confirmed the formation of crystalline hexagonal ZnO phase (wurtzite structure) with an average crystal size of 21.23 nm. FESEM analysis suggests the formation of 57.32 nm of ZnO NPs and the particles are almost spherical and moderately polydispersed. FTIR showed the vibration peaks for alkaloids, flavonoids and phenolic compounds which could act as both a reducing agent and a stabilizer for the prepared NPs. The high colloidal stability of the NPs is confirmed from the high ξ potential (-33.6 mV). The synthesized NPs showed concentration-dependent antioxidant activity with an IC₅₀ of 47.67 µg/mL, indicating strong but lower potency than ascorbic acid (12.39 µg/mL). The prepared NPs were utilized for the application of antibacterial activity and anti-diarrheal activity. The NPs exhibited higher antibacterial activity for S. aureus pathogen (ZOI, 18.2 ± 0.4) among the four identified different gram-positive and gram-negative strains, with maximum efficacy observed at higher concentrations (100 µg/mL) of NPs dose. The biosynthesized ZnO NPs were found to have excellent anti-diarrheal activity for both the 200 mg/kg and 400 mg/kg NPs doses. Overall, this study shows a sustainable waste-to-nanomaterial strategy that combines green synthesis with multifunctional biomedical potential.
Graphical Abstract