Self-assembly variation of glycyrrhetinic acid epimers: Assembly mechanism and antibacterial efficacy between 18 α-GA and 18 β-GA

Colloids Surf B Biointerfaces. 2024 Oct:242:114120. doi: 10.1016/j.colsurfb.2024.114120. Epub 2024 Jul 23.

Abstract

Studies have confirmed that the spatial arrangement of chiral molecules has a decisive influence on supramolecular assembly. However, the effect of epimerization caused by the change of a single chiral center on the self-assembly of chiral molecules has not been reported. Herein, we explored a pair of epimers 18 α-glycyrrhetinic acid and 18 β-glycyrrhetinic acid from Glycyrrhiza uralensis Fisch, which had completely different medicinal activities. In this study, we found that these epimers of glycyrrhetinic acid showed distinct self-assembly properties under the condition of the deionized water and a small amount of DMSO solution. Interestingly, the cis-configured 18 β-GA could form a 'head-to-tail' interlaced structure and further self-assembled to form nanoparticles, while trans-configured 18 α-GA was connected in a "head-to-head" manner, and due to the excessive steric hindrance that made it difficult to assemble. This work not only clearly demonstrates the impact of epimerization due to changes in a single chiral center on the self-assembly of chiral molecules as well as biological activity, but also provides new insights into the self-assembly of natural organic molecules in the development of nanomedicines and biofunctional materials.

Keywords: Epimer; Glycyrrhetinic acid; Self-assembly; Staphylococcus aureus; Supramolecular.

MeSH terms

  • Anti-Bacterial Agents* / chemical synthesis
  • Anti-Bacterial Agents* / chemistry
  • Anti-Bacterial Agents* / pharmacology
  • Escherichia coli / drug effects
  • Glycyrrhetinic Acid* / analogs & derivatives
  • Glycyrrhetinic Acid* / chemistry
  • Glycyrrhetinic Acid* / pharmacology
  • Glycyrrhiza uralensis / chemistry
  • Microbial Sensitivity Tests
  • Nanoparticles / chemistry
  • Particle Size
  • Staphylococcus aureus / drug effects
  • Stereoisomerism

Substances

  • Glycyrrhetinic Acid
  • Anti-Bacterial Agents
  • 18alpha-glycyrrhetinic acid