Antiplasmodial and antimicrobial activities of e nt -abietane diterpenoids from the roots of Suregada zanzibariensis .

The root extract of Baill. afforded six previously described -abietane diterpenoids, namely 7-oxo--abieta-5(6),8(14),13(15)-trien-16,12-olide (), mangiolide (), 8,14:11,12-diepoxy-13(15)-abietane-16,12-olide (), 7,11,12-trihydroxy--abieta-8(14),13(15)-diene-16,12-olide (), 8α,14-dihydro-7-oxo-jolkinolide E (), jolkinolide A (), together with 3-sitosterol (), scopoletin () and vanillin (). Their structures were deduced through 1D and 2D NMR spectroscopic techniques, and HRESIMS, as well as by comparison of the NMR data with those reported in the literature. The crude extract and compounds - were evaluated for their antiplasmodial, antifungal and antibacterial activities. Mangiolide () showed strong antiplasmodial activity against chloroquine sensitive (D6) and resistant (W2) strains of with IC values of 0.79 and 0.87 µg/mL, respectively, while (IC 1.24 and 1.17 µg/mL) was less active than . Compound also displayed antimicrobial activity against , methicillin-resistant (MRSA) and vancomycin-resistant (VRE) with IC values of 1.20, 3.90 and 7.20 µg/mL, respectively.