Ameliorative antimalarial effects of the combination of rutin and swertiamarin on malarial parasites

To ameliorate the antimalarial activity via the combination of rutin (flavonoid) and swertiamarin (glycoside). The antimalarial effects were assessed by in vitro and in vivo methodology. In vitro antiplasmodial activity was assessed by using Plasmodium falciparum cultured media and determined the IC50 value of individual drugs and their combinations. In in vivo methodology, antimalarial effects of rutin, swertiamarin (200–280 mg/kg/day, p.o.) and their combination in 1:1, 1:2 and 2:1 ratios were investigated early and established malaria infections using Swiss albino mice infected with Plasmodium berghei. Chloroquine phosphate (5 mg/kg/day, p.o.) was used as the standard drug. IC50 values of the rutin and swertiamarin via in vitro study revealed (9.50 ± 0.29) μg/mL and (8.17 ± 0.17) μg/mL respectively. Whereas, the combination in 1:1 ratio [IC50 of (5.51 ± 0.18) μg/mL] showed better antiplasmodial activity against Plasmodium falciparum. In vivo results showed that rutin and swertiamarin had chemosuppressant effects in a dose-dependent manner, whereas, combination in 1:1 ratio possessed potential antimalarial activity similar to chloroquine phosphate. The drug interaction between rutin and swertiamarin revealed the synergistic effect on 1:1 ratio and additive effect on 1:2 and 2:1 ratios. The results of the in vitro and in vivo study clearly indicate that the combination (1:1) of rutin and swertiamarin showed potential antimalarial activity rather than an individual of each and their combinations 1:2 and 2:1.