Antimicrobial activity of the methanolic extract and compounds from the stembark of Garcinia lucida vesque (Clusiaceae)

We investigated hereby the methanolic crude extract of the stem bark of Garcinia lucida Vesque. The genus Garcinia (Clusiaceae or Guttiferae)consists of about 200 species mainly encountered in lowland rain forests of the tropical world, particularly in Africa and Southeast Asia1,2. 21Garcinia species are represented in Cameroon among which Garcinia lucida vesque3. Dichloromethane sub-fraction from the methanol crude extractof the stem bark of Garcinia lucida Vesque afforded eleven compounds namely putranjivic acid 1, methyl putranjivate 3, their intermediary lactone2, friedeline 4, cycloartenol 5, 1,2-dihydroxy-xanthone 6, 1-hydroxy-2-methoxyxanthone 7, betulinic acid 8, oleanolic acid 9, β-sitosterol 10 andstigmasterol 11. Except 5, all those compounds are reported for the first time from Garcinia lucida. The structures of isolated compounds wereestablished on the basis of 1D/2D NMR experiments, mass spectrometric and by comparison of data with those of the literature.The methanol crude extract and pure compounds from CH2Cl2 fraction were tested for their antimicrobial activity against Escherichia coli,Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus, and Candida albicans. The crude extract showed good inhibitory potentialwith a MIC value of 64 μg/mL on Candida albicans while pure compounds were poorly active. Only compound 5 exhibited moderate and selectedantimicrobial activity against E. coli and P. aeruginosa.