Antimicrobial, antioxidant, cytotoxic and apoptotic activities of Satureja khuzestanica

Abstract

Objective: Natural products with antimicrobial effect are currently investigated in order to eliminate the use of synthetic antibiotics that cause the resistance of microorganisms. This study determines the antibacterial, antioxidant activity, and also the cytotoxic and apoptotic effect of Satureja khuzestanica on various cancer cell lines. Materials and methods: The individual constituents were identified by their identical retention indices referring to known compounds from the literature. Methanol and ethanol extracts of S. khuzestanica (25 and 50 mg/(mL)) were screened against four Gram-positive and four Gram-negative bacteria. The plant extracts were tested for their antioxidant activity against 2,2-diphenyl1- picrylhydrazyl (DPPH) radical. The interaction between the extracts and plasmid DNA were analyzed by agarose gel electrophoresis. In addition, the cytotoxic activity of the extracts was evaluated on MCF-7, DLD-1, osteosarcoma, and fibroblast cell line. Finally, gene expression of caspase-3, Bax and Bcl-2 were investigated by real-time PCR. Results: Our result indicated that both extracts showed good inhibitory activity against both Gram-negative (Escherichia coli ATCC 35218) and positive (Bacillus subtilis ATCC 6633) bacteria. In addition, the methanol extract of S. khuzestanica had strong antioxidant activity (IC50= 37.0 +/- 0.3 mu g/mL). The extracts showed a strong effect on plasmid DNA. The methanol extract of S. khuzestanica showed a good concentration-dependent cytotoxicity. Finally, IC50= 47.00a +/- 1.21 mu g/mL, ethanol, and water extract had apoptotic effect in MCF-7 cell line. Discussion: MCF-7 was detected as the most sensitive cell line therefore further studies should be done on this plant extract as a potential anticancer agent against breast cancer.