BACTERICIDAL EFFECT OF THE SESQUITERPENE T-CADINOL ON STAPHYLOCOCCUS-AUREUS

The antimicrobial effects of the sesquiterpene T-cadinol, isolated from the Somalian traditional remedy, scented myrrh (resin of Commiphora guidottii Chiov., Burseraceae), were investigated. The compound was found to be active toward Staphylococcus aureus and Trichophyton mentagrophytes. The minimum inhibitory concentration of T-cadinol on S. aureus was 24-mu-g/mL and the lowest concentration exerting fungicidal effect on T. mentagrophytes was 2.3-mu-g/mL. The influence of T-cadinol cell viability in S. aureus, both in different growth-phases, and in the absence and presence of chloramphenicol, was studied. It could be concluded that T-cadinol has a bactericidal rather than a bacteriostatic effect, which acts also in the absence of growth. Furthermore, the effect of T-cadinol on S. aureus was analysed and documented with transmission electron microscopy. The electron micrographs clearly showed that T-cadinol interacted with the cell envelopes, causing bacterial lysis and subsequent fatal loss of intracellular material. The effect of the substance was thus characterized as bacteriolytic. The use of scented myrrh in traditional medicine as a remedy for wounds may then be in congruence with this bactericidal effect of T-cadinol toward the common wound pathogen S. aureus.