Background: The Zinc oxide Nanoparticles (ZnO NPs) were synthesized successfully
by using Tagetes erecta flower aqueous extract and evaluated for their antioxidant potential, antimicrobial
and cytotoxic potential.
Methods: Phytochemical screening of aqueous crude extract and synthesized ZnO NPs of Tagetes
erecta flower revealed the presence of alkaloids, flavonoids, carbohydrates, amino acids, tannins,
proteins, etc. The characterization was done by various spectral analyses. In vitro antioxidant activities
of synthesized ZnO NPs were found to possess concentration-dependent free radical scavenging
activity was carried on different free radicals i.e. DPPH and ABTS. Antimicrobial activity of
synthesized ZnO NPs was performed by agar well diffusion method and compared with control
ampicillin, while cytotoxic effects were determined by MTT assay against human cervical cancer
Results: UV-Visible spectra were conducted to confirm the synthesis of ZnO NPs and peak obtained
at 364.15nm. X-ray analysis confirmed the crystalline nature of the nanoparticles and the average
size of the nanoparticles was 30-50nm and was spherical shape analyzed by SEM. The synthesized
ZnO NPs showed antimicrobial activity against all tested microorganisms and a maximum
inhibition zone was found against E. coli in gram-negative and S. aureus in gram-positive bacteria.
Synthesized ZnO NPs were showed 50% cell viability at 26.53μg/ml against the HeLa cancer cell
Conclusion: The conclusion of this study suggests both the aqueous crude extract of Tagetes
erecta flower and synthesized ZnO NPs showed an excellent alternative source of antimicrobial
agent also an attractive selective cytotoxic activity against HeLa tested cancer lines, offering satisfying
‘safe and cheaper’ alternatives to conventional therapy protocols.