In vitro antiplasmodial effect of ethanolic extracts of coastal medicinal plants along Palk Strait against Plasmodium falciparum

Objective

To identify the possible antiplasmodial compounds from Achyranthes aspera (A. aspera), Acalypha indica (A. indica), Jatropha glandulifera (J. glandulifera) and Phyllanthus amarus (P. amarus).

Methods

The A. aspera, A. indica, J. glandulifera and P. amarus were collected along Palk Strait and the extraction was carried out in ethanol. The filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 µg/mL) of leaf, stem, root and flower extracts of A. aspera, A. indica, J. glandulifera and P. amarus were tested for antiplasmodial activity against Plasmodium falciparum. The potential extracts were also tested for their phytochemical constituents.

Results

Of the selected plants species parts, the stem extract of A. indica showed excellent antiplasmodial activity (IC₅₀= 43.81µg/mL) followed by stem extract of J. glandulifera (IC₅₀= 49.14µg/mL). The stem extract of A. aspera, leaf and root extracts of A. indica, leaf, root and seed extracts of J. glandulifera and leaf and stem extracts of P. amarus showed IC₅₀ values between 50 and 100 µg/mL. Statistical analysis revealed that, significant antiplasmodial activity (P<0.01) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes was also carried out and it showed that there were no morphological changes in erythrocytes by the ethanolic extract of all the tested plant extracts. The in vitro antiplasmodial activity might be due to the presence of alkaloids, glycosides, flavonoids, phenols, saponins, triterpenoids, proteins, and tannins in the ethanolic extracts of tested plants.

Conclusions

The ethanolic stem extracts of P. amarus and J. glandulifera possess lead compounds for the development of antiplasmodial drugs.