In vitro Antimalarial Activity of Solvents Extracts of Alstonia boonei Stem Bark and Partial Characterization of Most Active Extract(s)

Alstonia boonei, a plant locally called ‘Egbu’ in South Eastern Nigeria is used traditionally in the treatment of malaria in the region. This research was carried out to evaluate in vitro antimalarial activity of different solvents extract (aqueous, methanol, ethyl acetate, chloroform and hexane) of Alstonia boonei against NK-65 Chloroquine sensitive Plasmodium berghei infected mouse blood. The antimalarial activity of the extracts was determined by calculation of percentage parasitaemia. GCMS analysis was conducted for the detection of possible bioactive compound(s) in the most active extract(s). Results showed that all the extracts had intrinsic antimalarial properties that were dose dependent. Furthermore, there was a significant increase (p<0.05) in mean percentage anti-malarial activity of all the extracts when compared with the placebo (normal saline) and standard anti-malarial drugs Chloroquine and ACT, with aqueous extract showing highest antiplasmodial activity of 95.24% at 2000 µg/ml. GCMS results revealed the presence of 3-Nitrophthalic acid and coumarine as possible bioactive compounds presents in the extracts. The present study demonstrated that Alstonia boonei possess strong antimalarial activity with aqueous extracts possessing the highest activity. Thus, supporting the traditional use of the plant for the treatment of malaria.