| Abstract: | Two diterpenes from Juniperus excelsa, obtained by bioautography-guided isolation technique, were found to possess significant antibacterial activity in a two-fold serial dilution assay. (+)-Ferruginol (abieta-8,11,13-triene-12-ol) (1) and (?)-sandaracopimeric acid (isopimara-8(14), 15-diene-18-oic acid) (2) exhibited significant activity against Bacillus subtilis, Staphylococcus aureus and Streptococcus durans, while their corresponding 3β-hydroxy derivatives [(hinokiol (3) and 3β-hydroxysandaracopimeric acid (4), also isolated from J. excelsa)] were found to be inactive. (+)-Ferruginol, in addition, demonstrated strong activity against Mycobacterium smegmatis, M. intracellulare, M. xenopi and M. cheloni. The minimum inhibitory concentrations were determined for all compounds isolated from the active bioautographic zones, and were compared to those of the standard antibiotics chloramphenicol and streptomycin sulphate. |
