Efficacy of medicinal plants and their derived biomolecules against apicomplexan pathogen

Background: Many apicomplexan pathogens pose significant threats to humans and domestic animals, with the lack of effective drugs and drug resistance representing major challenges in disease management. To address this, the search for new and potent antimalarial drugs is crucial. Plant-based formulations offer a promising alternative for such drug development. Here, we evaluated the in vitro antiplasmodial activity of nine plant extracts, traditionally used to treat fever-like symptoms in Bangladesh. Methods: We assessed the antimalarial activity of plant extracts by using the Plasmodium falciparum 3D7 growth inhibition assay, an invasion assay, and a cytotoxicity assay. Results: Of the nine plants studied, ethanolic and methanolic leaf extracts of Ficus hispida , Streblus asper , and Boerhavia repens exhibited high antiplasmodial activity, with IC ₅₀ values of 9.31, 4.13, 9.63 μg/ml (ethanolic) and 15.58, 6.63, 7.58 μg/ml (methanolic), respectively, and minimal toxicity (cell viability >80%). Clerodendrum viscosum displayed antiplasmodial effects with IC ₅₀ values of 42.43 μg/ml (ethanolic) and 27.01 μg/ml (methanolic). Adhatoda vasica , Mussaenda corymbosa , and Amaranthus spinosus ethanolic extracts showed antimalarial effects with IC ₅₀ values of 59.59 μg/ml, 57.09 μg/ml, and 64.14 μg/ml, respectively. However, methanolic extracts of Adhatoda vasica and Amaranthus spinosus had IC ₅₀ values >100 μg/ml. The ethanolic and methanolic extracts of Adhatoda vasica , Amaranthus spinosus , Ficus hispida , Streblus asper , and Boerhavia repens significantly reduced parasitemia by inhibiting invasion into erythrocytes. Conclusions: This study highlights the robust antimalarial activity and low cytotoxicity of leaf extracts of Ficus hispida , Streblus asper , and Boerhavia repens , indicating the presence of antimalarial compounds that warrant further investigation.