Mentha piperita was used as a chelating agent to synthesize zinc oxide nanoparticles (ZnO-AE-NPs). The anti-proliferative, cytotoxic, and anti-microbial potential of the biosynthesized ZnO-AE-NPs were studied using 3-[4, 5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT), trypan blue, and disc diffusion, respectively. A comprehensive analysis of the ZnO-AE-NPs was conducted utilizing various techniques, X-ray diffraction (XRD) analysis, UV-vis (UV-vis), Fourier-transform infrared (FTIR), Scanning electron microscopy (SEM and energy-dispersive X-ray (EDX)), and Zeta sizer. The results of the analysis showcase the ZnO-AE-NPs to have average particle size and zeta potential of 23 nm and +42 mV, respectively, ascertained by the Zeta sizer. The FTIR, XRD, and EDX spectra ascertained the formation of ZnO-AE-NPs. UV-vis spectra revealed an absorption peak at 368 nm due to a colour change from light green to brown, confirming the synthesis and good stability of the nanoparticle, and spherical morphology was observed from our SEM analysis. Furthermore, The ZnO-AE-NPs revealed cytotoxic and anti-proliferative potential against MDA-MB 231 cells with increased concentration. A robust antimicrobial potential was observed in Escherichia coli and Staphylococcus aureus. ZnO NPs AE revealed anti-microbial, anti-proliferative potential on E. coli and S. aureus, and MDA-MB 231 cells