In vitro evaluation of the antiplasmodial activity and phytochemical screening of five plants extracts from the traditional pharmacopoeia in Côte d'Ivoire

The resistance of Plasmodium falciparum to current antimalarial drugs, namely artemisinin derivatives associated with a partner molecule, requires the search for new therapeutic alternatives through traditional pharmacopoeia, rich in medicinal plants. The aim of this study is to assess the in vitro anti-plasmodial activity of leaf extracts from five plants selected for their traditional use against malaria. An ethnopharmacological survey was carried out in Agboville to identify plants traditionally used against malaria in this region. The leaves of these plants were harvested, dried and extracted using aqueous and hydroethanolic solvents. The extracts obtained were then subjected to an in vitro anti-plasmodial test using SYBR GREEN to assess their ability to inhibit the growth of Plasmodium falciparum. Phytochemical screening and high-performance liquid chromatography-mass spectrometry (LC-MS) was carried out to identify the chemical compounds present in the extracts. In total, ten extracts from the dried leaves of five plants were tested on clinical isolates of Plasmodium falciparum. Of these, only Momordica charantia extracts showed an IC50 ≤ 5 µg/ml, namely 1.93 µg/ml for the hydroethanolic extract and 4.35 µg/ml for the aqueous extract. The anti-plasmodial activity of these extracts was described as powerful. Extracts from other plants showed IC50 values ranging from 16.19 µg/ml to 31.43 µg/ml, indicating moderate anti-plasmodial activity. Phytochemical analyses mainly revealed the presence of flavonoids, alkaloids, polyterpenes and phenolic acids, suggesting that these compounds may be responsible for the anti-plasmodial activity observed. In conclusion, the search for natural products capable of blocking the transmission of malaria must be pursued with determination, and further studies are needed before the formulation of phytomedicines from these plants can be envisaged.