Isolation and characterization of novel antibacterial compound from an untapped plant, Stereospermum fimbriatum

Nat Prod Res. 2020 Mar;34(5):629-637. doi: 10.1080/14786419.2018.1494170. Epub 2018 Nov 23.

Abstract

Stereospermum fimbriatum or locally known as "Chicha" is traditionally used for itchy skin, earache, stomachache and postpartum treatments. This study was designed to evaluate the antimicrobial potential of S. fimbriatum's stem bark against 11 pathogens and isolate its bioactive compound. Successive soxhlet extraction was conducted using n-hexane, dichloromethane (DCM) and methanol. Disc diffusion, minimum inhibitory and bactericidal concentration (MIC & MBC) assays were done to examine the antimicrobial activity. Bioassay-guided isolation was conducted on S. fimbriatum's extract. The DCM extract of stem bark (DS) was the most potent extract followed by n-hexane extract of the stem bark (NS). A novel compound was isolated and coded as C1 which demonstrated potent antibacterial effects with the MIC values as low as 3.13 µg/mL to 6.25 µg/mL, against S. epidermidis, MRSA and S. aureus. Thus, S. fimbriatum could be a potential source of antimicrobial agents for the treatment of skin infections, specifically, MRSA.

Keywords: Stereospermum fimbriatum; angucycline; antibacterial; chicha; isolation.

MeSH terms

  • Anti-Bacterial Agents / isolation & purification*
  • Anti-Bacterial Agents / pharmacology
  • Bignoniaceae / chemistry*
  • Methicillin-Resistant Staphylococcus aureus / drug effects
  • Microbial Sensitivity Tests
  • Plant Bark / chemistry
  • Plant Extracts / pharmacology
  • Staphylococcus aureus / drug effects

Substances

  • Anti-Bacterial Agents
  • Plant Extracts