Green Synthesis of Zinc Oxide Nanoparticles Using Aloe vera Leaf Extract and Evaluation of the Antimicrobial and Antioxidant Properties of the ZnO/Regenerated Cellulose Film.

The utilization of plant extracts in the synthesis of zinc oxide nanoparticles is recognized as one of the most environmentally friendly approaches. This study focuses on the green synthesis of zinc oxide nanoparticles (ZnO NPs) using Aloe vera leaf extract (ALE) as both the reducing and capping agents. Additionally, an antimicrobial regenerated-cellulose composite film (RCF) incorporating ZnO NPs (ZnO/RCF) was prepared through the immersion phase-conversion method. The structure and morphology of ALE-ZnO NPs and ZnO/RCF were characterized, and the antimicrobial properties of ZnO/RCF were assessed using the inhibition zone method. UV and FTIR spectra confirmed the presence of the Zn–O bond stretching mode. HR-TEM and XRD results indicated that ALE-ZnO NPs were formed in a pure crystalline state, exhibiting sphere-like shapes with an average crystallite size of approximately 25 nm. SEM images and EDS mapping of ZnO/RCF demonstrated that ALE-ZnO NPs were well dispersed and stabilized in the cellulose matrix. Furthermore, ZnO/RCF exhibited increased antimicrobial activity against Kosakonia Cowanii and Alternaria alternata strains with higher content of ALE-ZnO NPs. The maximum zone of inhibition was observed for ZnO-10/RCF against Kosakonia Cowanii (22 ± 0.4 mm). Additionally, ZnO/RCF displayed antioxidant activity as a DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenger. This study suggests that ZnO/RCF holds potential applications in industries such as food packaging, pharmaceuticals, agriculture, and cosmetics. [ABSTRACT FROM AUTHOR]