Metabolites (Feb 2023)

Constituents of the Stem Bark of <i>Trichilia monadelpha</i> (Thonn.) J. J. De Wilde (Meliaceae) and Their Antibacterial and Antiplasmodial Activities

  • Arnauld Kenfack Djoumessi,
  • Raymond Ngansop Nono,
  • Beate Neumann,
  • Hans-Georg Stammler,
  • Gabin Thierry Mbahbou Bitchagno,
  • Noella Molisa Efange,
  • Celine Nguefeu Nkenfou,
  • Lawrence Ayong,
  • Bruno Ndjakou Lenta,
  • Norbert Sewald,
  • Pépin Nkeng-Efouet-Alango,
  • Jean Rodolphe Chouna

DOI
https://doi.org/10.3390/metabo13020298
Journal volume & issue
Vol. 13, no. 2
p. 298

Abstract

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The chemical investigation of the EtOH extract from the stem bark of Trichilia monadelpha (Thonn.) J. J. De Wilde afforded two new limonoids (1 and 2): 24-acetoxy-21,25-dihydroxy-21,23-epoxytirucall-7-en-3-one (1) and (6R)-1-O-deacetylkhayanolide E (2), together with eleven known compounds (3–13), including additional limonoids, flavonoids, triterpenoids, steroids, and fatty acid. Their structures were determined using 1D- and 2D-NMR experiments, ESI mass spectrometry, and single crystal X-ray diffraction analysis. The antibacterial and antiplasmodial activities of the extracts, sub-extracts, fractions, and some of the isolated compounds were evaluated in known pathogenic strains, including Staphylococcus aureus and Plasmodium falciparum. Fraction E (n-Hex/EtOAc 30:70, v/v) showed significant activity against S. aureus ATCC 25923 with a MIC value of 3.90 µg/mL, while one of its constituents (epicatechin (9)) exhibited significant activity with MIC values of 7.80 µg/mL. Interestingly, grandifotane A (6) (IC50 = 1.37 µM) and khayanolide D (5) (IC50 = 1.68 µM) were highly active against the chloroquine-sensitive/sulfadoxine-resistant plasmodium falciparum 3D7 strain, unlike their corresponding plant extract and fractions.

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