Comparison of Nigella sativa Seeds Extract and Respective ZnO NPs for Antimicrobial, Antioxidant and Cytotoxic Potential

In the present work, ZnO NPs were synthesized by using zinc acetate salt solution and seeds extract of Nigella sativa L. in a ratio of 9:1, for a green chemistry approach being nontoxic and ecofriendly in nature. Colour change confirmed the formation of ZnO NPs. The synthesized nano structures characterized by UV-Vis spectrophotometer, SEM, EDX, FTIR and XRD. To evaluate the therapeutic efficacy of ZnO NPs various bioassays were performed such as antifungal, antibacterial, antioxidant and brine shrimp cytotoxicity.UV-Vis spectrophotometer generated the absorption peak at 370 nm for ZnO NPs. SEM results indicated the average size of ZnO NPs 35 nm with a hexagonal and crystalline structure which was confirmed through XRD. The active functional group of amines, methyl and OH" were analyzed through FTIR. Zinc is the major constituent in the sample confirmed by the EDX spectrum. Biologically synthesized nanoparticles of Nigella sativa seeds extract showed significant antibacterial activity at 100 ppm, 80% antifungal activity at 25 ppm as compared to plant extract (15%). ZnO NPs also showed significant antioxidant potential (70%) at 100 ppm as compared to plant extract (51.72%) with EC50 65.06 ppm for plant extract and 53.46 ppm for ZnO NPs. Significant cytotoxicity potential also observed against the brine shrimps with IC50 of ZnO NPs 147.4 ppm as compared to plant extract with IC50 258.9 ppm. This is the first report stating the synthesis and antimicrobial, antioxidant and cytotoxic potential of ZnO NPs of Nigella sativa seed extract. These ZnO NPs can be further explored in various biomedical applications at the commercial level. Keywords: antimicrobial, antioxidant, cytotoxic, Nigella sativa, zinc oxide nanoparticles