Samuel Korsah, Nathaniel Nene Djangmah Nortey, Christian Akakpo, Felix Kwame Zoiku, Jessica Korsah, Miriam Tagoe, Joseph Kwao Amanor, Babu Jacob Yamba, Josephine Akosua Ofori-Asamoah
Cryptolepis sanguinolenta and Azadirachta indica exerted synergistic interactions against 3D7 and DD2 strains of Plasmodium falciparum. The extracts are desirable when used in combination rather than alone.
INTRODUCTION: Azadirachta indica and Cryptolepis sanguinolenta are herbs commonly used together in polyherbal products in Ghana for the treatment of malaria.
AIM: This research investigated the combined effects of Azadirachta indica and Cryptolepis sanguinolenta extracts against chloroquine-sensitive (3D7) and resistant (DD2) strains of Plasmodium falciparum.
METHODS: In vitro antimalarial activity was assayed on the aqueous extracts of both plants using a fluorescence-based SYBR Green assay. The combined effects of the two extracts were determined using computer-based software, CompuSyn.
RESULTS: Aqueous extracts of Azadirachta indica and Cryptolepis sanguinolenta exerted high antimalarial activities (IC50 ≤ 10 μg/mL) against both 3D7 and DD2 strains of the Plasmodium falciparum. Azadirachta indica and Cryptolepis sanguinolenta displayed strong synergistic activity with combination index (CI) values ranging from 0.15 to 0.52 for 53%-99% inhibition of 3D7 Plasmodium falciparum. Also, CI values for the plants against DD2 were from 0.23 to 0.61 with corresponding 30%-97% parasitemia inhibitions. Azadirachta indica and Cryptolepis sanguinolenta exerted a dose reduction index (DRI) value greater than 1 (DRI > 1) in both strains.
CONCLUSION: Cryptolepis sanguinolenta and Azadirachta indica exerted synergistic interactions against 3D7 and DD2 strains of Plasmodium falciparum. The extracts are desirable when used in combination rather than alone.