Shelf-life enhancement of Gerbera jamesonii flowers by the green synthesised ZnO nanoflowers

This study has been aimed to synthesise the self-assembled, flower-shaped zinc oxide nanoparticles (ZnO NFs) by using a green synthesis method using the aqueous extract from the peels of Citrus reticulata. Both HR-TEM and Fe-SEM analyses have confirmed the flower-like morphology for the synthesised nanoparticles. The observed zeta potential value of −48.0 mV further indicated its highly stable structure. The X-ray diffractogram of the ZnO NFs showed the characteristic diffraction peaks for the crystalline ZnO without any impurity peak, indicating the complete reduction into nanoparticles and thereby, the formation of pure crystalline ZnO NFs. The antibacterial activity of ZnO NFs was then studied using the standard well diffusion method and demonstrated significant bactericidal effects against Staphylococcus aureus and Escherichia coli, with a minimum inhibitory concentration (MIC) of 0.048 mg mL−1. Additionally, the ZnO NFs were evaluated for their potential to enhance the shelf life of Gerbera jamesonii flowers when treated with different concentrations in a chitosan-based solution. The ZnO NFs supplemented solution here was found to preserve the freshness of the cut flowers for up to 9.3 ± 0.3 days compared to the 3-day shelf life of the control group. These findings suggest ZnO NFs to have significant antibacterial properties and can effectively extend the shelf life of cut flowers.