Synthesis of zinc oxide nanoparticles by Pterolobium hexapetalum (roth) santapau and wagh extract and their biological applications

The indenture of the green approach in synthesizing metal oxide nanoparticles has resulted in greater stoutness and favorable dimensions of nanoparticles since they are synthesized using a single-step process. In this study, using Pterolobium hexapetalum aqueous leaf extract (P. hexapetalum) as a precursor, zinc acetate was reduced to obtain zinc oxide nanoparticles (ZnO-NPs) using a green synthesis approach. The synthesized ZnO-NPs were characterized by UV-Vis, XRD, FT-IR, EDAX, and HR-TEM with an SAED pattern. According to the findings, the UV-visible spectra result showed an absorbance peak at 370 nm. The FT-IR study of the synthesized ZnO-NPs revealed the presence of various functional groups. The HR-TEM result displayed a spherical shape with a size of 10–93 nm for synthesized ZnO-NPs. The X-ray diffraction (P-XRD) spectra confirmed the crystalline nature of the synthesized ZnO-NPs. The outcome of the edax spectrum confirmed the high purity of the Zn element that was present in the synthesized ZnO-NPs. Hemolytic activity of the synthesized ZnO-NPs was carried out against human red blood cells (RBCs), and it appeared that ZnO-NPs had less toxicity with a lysis percentage of 0.6% at a higher dosage of 100 μg/mL. The synthesized ZnO-NPs showed excellent antibacterial activity against Pseudomonas aeruginosa (17.8 mm). The synthesized ZnO-NPs displayed significant antioxidant activity against the DPPH radical scavenging assay with an IC50 value of 118.14 μg/mL. The anticancer activity of the synthesized ZnO-NPs revealed superior activity against the breast cancer cell line (MCF-7) with an IC50 value of 22.91 μg/mL. Additionally, the synthesized ZnO-NPs exhibited outstanding larvicidal activity on Cx. quinquefasciatus larvae with LC50 and LC90 values of 4.178 mg/mL and 16.157 mg/mL, respectively. Thus, plant-based synthesized ZnO-NPs exhibited significant biological activities, and hence, they can be considered a potential source for the development of innovative drugs.