Accepted 29th January, 2019.
Antioxidants, as natural compounds have been documented to possessscavenging abilities which helps in fighting body infections.Therefore, the aim of this study was to analyse the phytochemical constituents and antioxidant potentialof some medicinal plants reported to possess anti-viral activity in Malawi. The antioxidant potentials ofAeschynomene nyassana, Phyllanthus amarus, Euphorbia whyteana, Rhus acuminatissima and Ericae milanjiensisplants were evaluated using DPPH, FRAP, Reducing power, Nitric oxide scavenging activity and HPTLC while phytochemical analysis was done using spectrophotometric techniques.The phytochemical analysis showedthe presence of saponins, flavonoids, alkaloids,phenolic in the plant extracts. The results showed that ascorbic acid had significantly higher DPPH scavenging activity as compared to the plant extracts at all levels.NO scavenging activity demonstrated a significant dose dependent decreaseexcept forR. acuminatissinia.A. nyassanarevealed reducing power ability that was significantly greater as compared to Ascorbic acid. In HPTLC analysis, DPPH pale-yellow coloured spots were observedwhile the phenolic active blue colour spots were observed only in A. nyassana,P. amarus,R. acuminatissiniaand E. milanjiensis. Therefore,this study recommends further research on the 5 plants should be undertaken in order to inform science of traditional use in Malawi.
Keywords: Antioxidant, phytochemical compounds, reactive oxygen species, medicinal plants, High performance thin-layer chromatography, viral infections.