Two antibacterial spiro compounds from the roots of Artemisia pallens wall: evidence from molecular docking

Abstract

Bioassay-guided isolation from acetone extract of the roots of Artemisia pallens Wall yielded two spiro compounds (1 and 2). The structures of these compounds were determined on the basis of spectroscopic techniques such as IR, MS, 1 D and 2 D- NMR. The acetone extract, fractions and the isolated two compounds were investigated for their antibacterial activity against two gram negative (E. coli, P. aeruginosa) and two gram positive (S. aureus, B. subtilis) bacterial strains. Compound (2) showed the best spectra of activity with IC₅₀ and MIC values between 2.48–3.08 and 12.78 − 21.77 µM and Compound (1) with 2.57–3.69 and 38.17 − 80.57 µM, respectively, for the four bacterial strains, whereas inactive against Mycobacterium tuberculosis. Molecular docking study could further help in understanding the various interactions between these compounds and DNA gyrase active site in detail and thereby could provide valuable insight into the mechanism of action.

Graphical Abstract

Keywords:

• Artemisia pallens
• Asteraceae
• spiro compound
• antibacterial activity
• antimycobacterial activity
• molecular docking

Acknowledgements

Authors are grateful to Prof. P. B. Buchade, Principal, MES Abasaheb Garware College, Pune, India and Dr. Sourav Pal, Director, National Chemical Laboratory, Pune, India for providing necessary facilities. The authors also would like to acknowledge Schrödinger Inc. for providing the Academic license of Schrödinger Molecular Modeling Suite that has helped to perform the molecular modeling.

Disclosure statement

The authors have no conflict of interest.