Moshi, Mainen J.2023-08-112023-08-112013Magadula, J.J., Mwangomo, D.T., Moshi, M.J. and Heydenreich, M., 2013. A novel γ-lactone and other constituents of a Tanzanian Antidesma venosum. Spatula DD Peer Rev J Complementary Med Drug Dis, 3(1), p.7À12.DOI 10.5455/spatula.20130402070601http://hdl.handle.net/123456789/1128SUMMARY AIM: This study aimed at investigating the antimicrobial potential of isolated compounds from a Tanzanian Antidesma venosum. METHODS: The pure compounds were isolated from the stem and root barks of A. venosum using standard column chromatography procedures with silica gel as a stationary phase and organic solvents of different polarities as mobile phases. Antimicrobial activity was determined using broth microdilution method against different bacteria and fungi. RESULTS: Repeated column chromatography of the ethanol extract of the root bark of A. venosum led to the isolation of a new γ-lactone compound, namely (3R,4R,5S)-4-hydroxy-5-methyl-3-tetradecanyl γ-lactone (1) and β-sitosterol, while investigation of the stem bark afforded two known triterpenoids, friedelin (2) and lupeol (3) as well as a mixture of known phytosterols, β-sitosterol and stigmasterol. Their structures and absolute configurations were determined by using combined spectroscopic methods. Compound 1 didn’t display antimicrobial activity even at the maximum concentration tested (MIC values > 5mg/ml) against all tested strains. Friedelin (2) was the most active compound with MIC of 0.1875 mg/ml against Staphylococcus aureus (ATCC 25923) and Streptococcus pyogenes (clinical isolate) while lupeol (3) had weak antibacterial activity against S. aureus and S. pyogenes with MIC of 1.25 mg/ml. No inhibition was observed against other tested strains. CONCLUSION: These findings indicate that compound 2 is the main contributor for the reported activity in the stem bark, while synergism is suggested to be a causative of high antimicrobial activity reported from root extracts.enAntidesma venosumTriterpenoidsAntimicrobial activityArticle