Abstract

In this study, resinous exudate fromMadia sativawas analyzed by GC-MS. The major bioactive compounds 13,14,15-trihydroxylabd-7-ene (14) and 3,14,15-trihydroxylabd-8-ene (15) were isolated and their structures were determined by NMR. The antifungal activity of the resinous exudate and the labdanes compounds was evaluated using the inhibitory effects on the mycelial growth of plant pathogenPhytophthora cinnamomicausing root rot of various crops. The evaluation of the resinous exudate showed no inhibition over 50% at 75 mg/L, while compound15had the stronger effect on the myceliar growth ofP. cinnamomi, with a 94.6% inhibition at 175 mg/L. The same way, the mixture of both compounds in equal parts did not show a synergistic effect but showed similar percentages of mycelial growth inhibition from 25 mg/L with respect to the compounds separately.