ANOVA, analysis of variance; Algae; Antioxidant; Aquatic-ecosystem; BG-11, blue green-11; BSA, bovine serum albumin; CAT, catalase; CDH, central drug house; DDW, double distilled water; FTIR, fourier-transform infrared spectroscopy; Fe2O3, ferric oxide; IC50, half maximal inhibitory concentration; JCPDS, Joint Committee on Powder Diffraction Standards; LDH, lactate dehydrogenase; MDA, malondialdehyde assay; NADH, nicotinamide adenine dinucleotide (reduced form); NCBI, national center for biotechnology information; NPs, nanoparticles; Nanoparticles; OD, optical density; PBS, phosphate-buffered saline; PDI, polydispersity index; ROS, reactive oxygen species; SD, standard deviation; SEM, scanning electron microscopy; SOD, superoxide dismutase; Stress; TEM, transmission electron microscopy; UV, ultra violet; XRD, X-ray diffraction; ZnO, zinc oxide