Antioxidant and anti-plasmodial activity of extracts from three Ugandan medicinal plants

Abstract

Extracts from three plants; Hallea rubrostipulata, Vernonia adoensis andZanthoxylum chalybeum, were tested for antioxidant activity using three assays2,2-Diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Ability of Plasma (FRAP) and total phenol content) and anti-plasmodial activity using an Enzyme-Linked Immunosorbent Assay (ELISA) on Plasmodium falciparum chloroquine sensitive strain MRA-285 line. The objective of the study was to find candidates for making anti-malarial phytomedicines. The water extract of H. rubrostipulata showed very high anti-plasmodial activity (IC50= 1.95 µg/ml) and high antioxidant activity as well. Thirteen other extracts had high anti-plasmodial activity ranging from 2.14 to 3.63 µg/ml (chloroquine IC50= 8 µg/ml). We found high correlation between the different antioxidant assays.   Key words: Hallea rubrostipulata, Vernonia adoensis, Zanthoxylum chalybeum,2,2-Diphenyl-1-picrylhydrazyl, fluorescence recovery after photobleaching, total phenolic compounds