Hibiscus sabdariffa L. petal biomass: A green source of nanoparticles of multifarious potential

Abstract

Plant biomass is the largest and amply available biomass on the earth. Petals of flowering plants serve as an excellent raw material to synthesize nanoparticles. Biologically prepared silver nanoparticles (AgNPs) have garnered interest due to their simple and cost-effective green approach compared to chemical and physical methods. This investigation aimed to analyze the antibacterial, antioxidant, and antibiofilm properties of AgNPs synthesized from Hibiscus Sabdariffa L. petal extract and assess their potential as a stabilizing agent. A surface plasmon resonance peak at 421 nm confirmed the formation of AgNPs in the ultraviolet–visible (UV–vis) range. Additionally, size and morphological studies of the AgNPs were obtained using Scanning electron microscope (SEM) and X-ray diffraction (XRD) techniques. The identification of functional groups that are responsible for the stabilizing layer of AgNPs was achieved through Fourier transform infrared spectroscopy (FTIR) analysis. The antioxidant activity of synthesized AgNPs was investigated using the DPPH and ABTS radicals; the best performance was found in the scavenging of the DPPH radical, with an IC50 value of 37.71 ± 0.07 μg/ml. AgNPs actively suppressed the growth of four pathogenic bacteria (Shigella dysenteriae, Shigella boydii, Staphylococcus aureus, and Escherichia coli). Notably, Escherichia coli biofilm formation was absent at 40 and 80 g/ml of AgNPs up to 96 h. Finally, the overall findings of this present study confirmed that the AgNPs prepared from Hibiscus Sabdariffa petal extract can be used as antioxidant, antimicrobial, and antibiofilm preparations.