Anti-malarial Activity of Isoquinoline Alkaloids from the Stem Bark of Actinodaphne macrophylla.

Seven isoquinoline alkaloids isolated from the bark of Actinodaphne macrophylla in this study demonstrated in vitro antiplasmodial activities against Plasmodium falciparum 3D7 with IC50 values of 0.08 µM, 0.05 µM, 1.18 µM, 3.11 µM, 0.65 µM, 0.26 µM, and 1.38 µM for cycleanine, 10-demethylxylopinine, reticuline, laurotetanine, bicuculine, α-hydrastine and anolobine, respectively, which are comparable with the reference standard, chloroquine. 10-Demethylxylopinine was found to be the most active of these compounds.