Evaluation of the preservative efficacy of green‐synthesized <scp>ZnO</scp> Nanoparticles using <scp><i>Cucumis sativus</i></scp> in cream formulations

Abstract Due to concerns about the safety of preservatives in cosmetic formulations, there is an urgent need to explore eco‐friendly alternatives that do not pose a risk to consumers. Zinc oxide nanoparticles (ZnO NPs) are promising preservatives for pharmaceutical and cosmetic products. In this study, ZnO NPs were synthesized using Cucumis sativus (cucumber) extract as a stabilizing agent and zinc acetate dihydrate as a precursor. Polyphenols, terpenoids, and flavonoids in cucumber extract act as capping agents and facilitate the reduction of metal ions to form ZnO NPs. Synthesized ZnO NPs were characterized using various techniques, including powder x‐ray diffraction, x‐ray fluorescence, scanning electron microscopy, Fourier transform infrared spectroscopy, photoluminescence and spectroscopy UV–Vis. The effectiveness of ZnO NPs as a preservative in cream formulation was evaluated along with their antioxidant and antibacterial properties against Gram‐positive and Gram‐negative bacteria. This study introduces a new green synthesis method to produce ZnO NPs using C. sativus extract. This eco‐friendly and cost‐effective approach is a sustainable alternative for nanoparticle synthesis. It is worth noting that this is the first time that zinc oxide nanoparticles are used as a natural preservative in a moisturizing cream formulation. The resulting cosmetic formulation represents a unique advancement in cosmetic science that meets consumer demands for safe and eco‐friendly skin care products while utilizing the preservative properties of ZnO NPs. This research has significant potential to change the cosmetics industry by providing natural and sustainable alternatives to traditional preservatives.