Antibacterial terpenes from the oleo-resin of Commiphora molmol (Engl.).
Two octanordammaranes, mansumbinone (1) and 3,4-seco-mansumbinoic acid (2), and two sesquiterpenes, beta-elemene (3) and T-cadinol (4) have been isolated from the oleo-resin of Commiphora molmol (Engl.). The structures of these compounds were established unambiguously by a series of 1D and 2D-NMR analyses. We have also unambiguously assigned all (1)H and (13)C NMR resonances for 2 and revised its (13)C data. The crude extract of the oleo-resin of C. molmol displayed potentiation of ciprofloxacin and tetracycline against S. aureus, several Salmonella enterica serovar Typhimurium strains and two K. pneumoniae strains. The antibacterial activity of terpenes 1-4 was determined against a number of Staphylococcus aureus strains: SA1199B, ATCC25923, XU212, RN4220 and EMRSA15 and minimum inhibitory concentration (MIC) values were found to be in the range of 4-256 microg/ml. The highest activity was observed by the seco-A-ring octanordammarane 2 with an MIC of 4 microg/ml against SA1199B, a multidrug-resistant strain which over-expresses the NorA efflux transporter, the major characterized antibiotic pump in this species. This activity compared favorably to the antibiotic norfloxacin with an MIC of 32 microg/ml. Compound 2 also displayed weak potentiation of ciprofloxacin and tetracycline activity against strains of Salmonella enterica serovar Typhimurium SL1344 and L10.
Rahman
M Mukhlesur
MM
Centre for Pharmacognosy and Phytotherapy, School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, UK.
Garvey
Mark
M
Piddock
Laura J V
LJ
Gibbons
Simon
S
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D029744:Commiphora / Q000737:chemistry*; D007711:Klebsiella pneumoniae / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D012486:Salmonella typhimurium / Q000187:drug effects; D013729:Terpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D013729:Terpenes