A novel strategy of nanosized herbal Plectranthus amboinicus, Phyllanthus niruri and Euphorbia hirta treated TiO2 anoparticles for antibacterial and anticancer activities

Titanium dioxide nanoparticles exhibit good anticancer and antibacterial activities. They are known to be environmentally
friendly, stable, less toxic, and have excellent biocompatibility nature. Due to these properties, they are well suited for biological applications particularly in biomedical applications such as drug delivery and cancer therapy. In this research article,
three medicinal herbs namely, Plectranthus amboinicus (Karpooravalli), Phyllanthus niruri (Keezhanelli), and Euphorbia
hirta (Amman Pacharisi), were used to modify the surface of the TiO2 nanoparticles. The synthesized nanoparticles were
subjected to various characterization techniques. The samples are then subjected to MTT assay to determine cell viability.
KB oral cancer cells are used for the determination of the anticancer nature of the pure and bio modifed nanoparticles.
It is observed that Plectranthus amboinicus–Phyllanthus niruri modifed TiO2 nanoparticles exhibit excellent anticancer
activities among other bio modifed and pure samples. The samples are then examined for antibacterial activities against
three Gram-negative bacterial strains namely, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and two
Gram-positive bacterial strains namely, Staphylococcus aureus and Streptococcus mutans, respectively. Among the modifed
and pure samples, Plectranthus amboinicus showed good antibacterial activity against Gram-positive and Gram-negative
bacteria. In the Flow cytometry analysis, the generation of p53 protein expression from Plectranthus amboinicus–Phyllanthus niruri modifed TiO2 nano herbal particles shows the anti-cancerous nature of the sample. Then to determine the toxic nature of the Plectranthus amboinicus–Phyllanthus niruri modifed TiO2 nano herbal particles against normal cells, the NPs were subjected to MTT assay against normal L929 cells, and it was found to be safer and less toxic towards the normal cells.