Removal of microbial pathogens and anticancer activity of synthesized nano-thymoquinone from Nigella sativa seeds

Nigella Sativa (N. sativa) also known as black cumin seed and their active component thymoquinone are used as anti-inflammatory, antimicrobial and anticancer treatments. This study was aimed to synthesizes, characterize and to compare the antibacterial and anticancer activity of biologically synthesized nano thymoquinone (Tb-NPs) and chemically synthesized nano thymoquinone (Tc-NPs). The synthesis of nano-thymoquinone (nTQ) by chemical method was based on wet milling technique and biological method was using N. sativa seeds extract. The synthesized nTQ was characterized by UV, FTIR and FESEM analysis. The antimicrobial effects of Tc-NPs and Tb-NPs were evaluated against common antibiotic resistant organisms (Staphylococcus aureus, Pseudomonas aeruginosa, Enterococci faecalis, Klebsiella species and E. coli) using agar well diffusion. The results obtained from the UV spectra analysis showed highly intense absorption for both Tb-NPs and Tc-NPs at 242 nm and 319 nm respectively. The FTIR spectrum for Tb-NPs and Tc-NPs showed characteristics peaks at five different regions. The FESEM analysis of Tc-NPs showed micro/nano fibers and were homogeneously distributed and Tb-NPs showed spherical and agglomerates that were unevenly distributed. The cytotoxicity assay showed potential anticancer activity of Tb NPs with minimal concentration that of Tc NPs. Additionally these nTQ particles showed antimicrobial activity with removal of potential of bacterial and fungal pathogens by increased zone of inhibition. The obtained results concluded the biosynthesized nTQ have shown more activity because of the ability to remove potential of microbial pathogens and increase cancer cell death. These findings may encourage the use of biosynthesis method of nTQ over the chemosynthesis method. (C) 2021 The Authors. Published by Elsevier B.V.