Biosynthesis, Characterization, Antibacterial Activities, and Photocatalysis of Zinc Oxide Nanoparticles Using Allium Ambelloprasum (leeks) Leaves Extract

Abstract

The biosynthesis of nanomaterials using phytochemicals found in plants has attracted a lot of interest and is gaining traction as a viable alternative to traditional chemical processes.  In the current work, we used the aqueous leaf extract of Allium ampeloprasum (leek) as a reducing and stabilizing agent for the simple bio-fabrication of zinc oxide (ZnO) nanoparticles (NPs), owing to its alkaloids, coumarins, and flavonoids. Several methods, including, XRD, SEM, EDX, FT-IR, TEM, UV-visible spectroscopy, and TGA, were used to analyze the characteristics of the bio-fabricated ZnO-NPs.  An XRD study revealed that ZnO-NPs had a monoclinic structure with a crystallite dimension of 25.75 nm. The spherical structure of ZnO-NPs is confirmed by TEM and SEM morphological pictures, and their dispersion across surfaces shows decreased agglomerations. ZnO-NPs had a significant optical absorbance in the UV area at 368 nm and a large bandgap, indicating surface oxygen vacancies and charge carriers. The existence of Zn and O elements, as well as their Zn bonds, was identified using EDX and FT-IR spectroscopy. The photodegradation of methylene blue (MB) dye was studied using UV light irradiation, with a maximum degradation efficiency of 90.13% attained after 120 minutes of irradiation. Gram-positive Gram-negative bacteria and E. coli ZnO-NPs were tested against S.ococcus aureus, which showed the maximum zone inhibition (15.01 ± 0.85 mm) compared to E. coli (13.34 ± 0.04 mm). Thus, the degradation efficiency for MB dye and the zone inhibition results for both Gram-positive and Gram-negative bacteria indicate that the bio-fabricated ZnO-NPs from A. ampeloprasum (leek) leaves may have biological and environmental uses.