Anti-tubercular agents from Glycyrrhiza glabra

Curr Top Med Chem. 2015;15(11):1043-9. doi: 10.2174/1568026615666150317223323.

Abstract

Bioactivity guided isolation of Glycyrrhiza glabra (Leguminosae / Fabaceae) roots resulted in the characterization of 18β-glycyrrhetinic acid as a major anti-tubercular agent. Further, GA-1 was semi-synthetically converted into its nine derivatives, which were in-vitro evaluated for their antitubercular potential against Mycobacterium tuberculosis H37Rv using BACTEC-460 radiometric susceptibility assay. All the derivatives were active, but the benzylamide (GA-8, MIC 12.5μg/ml) and ethyl oxylate (GA-3, MIC 25.0 μg/ml) derivatives were significantly active against the pathogen. This was further supported by the molecular docking studies, which showed adequate docking (LibDock) scores for GA-3 (120.3) and GA-8 (112.6) with respect to the standard anti-tubercular drug, rifampicin (92.94) on the DNA-directed RNA polymerase subunit beta (rpoB) target site. Finally, the in silico pharmacokinetic and drug-likeness studies showed that GA-3 and GA- 8 possesses drug-like properties. This is the first ever report on the anti-tubercular potential of GA and its derivatives. These results may be of great help in anti-tubercular drug development from a very common, inexpensive, and non toxic natural product.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antitubercular Agents / chemical synthesis
  • Antitubercular Agents / chemistry*
  • Antitubercular Agents / pharmacokinetics
  • Antitubercular Agents / pharmacology*
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism
  • Biological Availability
  • Blood-Brain Barrier / drug effects
  • Chemistry Techniques, Synthetic
  • DNA-Directed RNA Polymerases
  • Drug Evaluation, Preclinical / methods
  • Glycyrrhetinic Acid / analogs & derivatives
  • Glycyrrhetinic Acid / chemistry
  • Glycyrrhiza / chemistry*
  • Humans
  • Intestinal Absorption / drug effects
  • Microbial Sensitivity Tests
  • Molecular Docking Simulation
  • Molecular Structure
  • Mycobacterium tuberculosis / drug effects*
  • Plant Roots / chemistry
  • Protein Conformation
  • Rats
  • Toxicity Tests / methods

Substances

  • Antitubercular Agents
  • Bacterial Proteins
  • rpoB protein, Mycobacterium tuberculosis
  • 18alpha-glycyrrhetinic acid
  • DNA-Directed RNA Polymerases
  • Glycyrrhetinic Acid