In-vitro anti-malarial activity of Chikadoma plant from the rainforest of Southern Nigeria

Abstract

Background: Malaria remains a life-threatening tropical disease. Due to the development of resistance to the commonly available orthodox antimalarials which of course, poses a great challenge in malaria-controlling-program, alternative and complementary approach becomes imperative thereby making phytotherapy a research focus. Objectives: To investigate the effect of chikadoma plant using its methanol leaf extract against a plasmodium-mediated tropical disease, malaria. Materials and Methods: The culture samples of Plasmodium (P.) falciparum from 20 symptomatic adult outpatients were used in the antimalarial in-vitro test. For cultivation of P. falciparum, the culture medium employed was Roswell Park Memorial Institute (RPMI) 1640. Optical microscopy was used for parasite quantification in the performance of antiplasmodial in-vitro assays. The leaf extract of chikadoma dissolved in dimethylsulphoxide (DMSO) was the treatment, prepared into 7 different levels of concentration (3.125, 6.25, 12.5, 25, 50, 100, and 200 mg/mL) while culture medium with the malarial parasite alone served as negative control. Micromalarial culture preceded by culture synchronized with sorbitol 5%, were divided into “control” and “treated groups”, followed by incubation in CO2 candle jar at 370C for 72 h. The percentage of parasitemia was measured 8 h, showing the activity of the extract on P. falciparum stages of proliferation. Thin blood smear from the erythrocytes layer was made and stained with 10% Giemsa for 30 mins to estimate the parasitemia. The antimalarial activity of the extract was calculated using Probit analysis by counting the 50% growth inhibition (IC50). Results: The growth of P. falciparum was inhibited by the extract on mature schizont stage; and the IC50 of the extract after 40 h incubation was 3.0 mg/mL. Conclusion: The leaf extract of chikadoma significantly has antimalarial effect in-vitro against P. falciparum.
 Keywords: Chikadoma; Lupinus arboreus; antimalarial activity; tropical disease; Nigeria.