Ex Vivo Protocol for Evaluating Anti-Schizont Activities and Phytochemical Analysis of Zingiber officinale Against Plasmodium falciparum

Abstract

The emergence of antimalarial drug resistance has spurred interest in the exploration of natural alternative therapeutic agents. This study aimed to optimise the ex vivo protocol for evaluating the anti-schizont activity of Zingiber officinale (ginger) extract against Plasmodium falciparum. The cold maceration method was used to obtain the extract. The schizont-inhibitory potential of varying concentrations (1.56 to 100 µg/ml) of ginger extract was assessed in a 96-well plate setup. The evaluation of parasitaemia and schizont count was conducted by Giemsa staining and microscopic examination. The results indicated that the ginger extract exhibited dose-dependent inhibition of schizont development in P. falciparum. At 100 µg/ml, the extract showed an average schizont count reduction to 4.25 ± 1.4 compared to the control group (32.15 ± 2.83). The extract’s viability also revealed a significant decrease in parasite viability, with an IC50 value of 11.90 ± 0.96 µg/ml, which is higher than that of the positive control, quinine, with an IC₅₀ of 3.14 ± 0.74 µg/ml. The average percentage inhibition of schizont formation increased at 100 µg/ml concentrations of ginger extract with 87.65% inhibition, suggesting promising antimalarial activity. Several compounds were identified, including 6'-O-P-coumaroyltrifolin, chlorogenic acid, and tetracenequinones. These compounds have been reported to possess antimalarial properties with mechanisms involving the disruption of parasite membrane integrity and interference with mitochondrial function. The study validates the potential of ginger extract as an antimalarial agent and also optimizes the ex vivo assay protocol for testing anti-schizont activity, which could serve as a foundation for future studies.