Insect repellent and antiplasmodial potentials of the leaves methanol extract of <i>Hyptis spicigera</i> lam

Hyptis spicigera lam belongs to the family lamiaceae. It is commonly known as black sesame and is traditionally used to treat diseases such as diarrhoea, headache, pneumonia, fever, chlolera, and as an insect repellent. This research work is aimed at determining the insect repellent potential and to evaluate the antiplasmodial activity of the methanol leaves extract of H. spicigera in plasmodium berghaei infected mice using suppressive and curative methods and chloroquine was used as positive control. Phytochemical constituents of the crude extract were analyzed using standard procedure. The results showed the presence of alkaloids, flavonoids, tannins steroids/terpenes, saponins and cardiac glycosides. The medial lethal dose (LD50) of the extract was estimated to be greater than 3807.13mg/kg indicating that, the plant is relatively moderately toxic. The chemo-suppressive potential of the extract at 50, 100, 200 and 3907 mg/kg doses indicate a significant (p<0.05) antimalarial activity with inhibition ranging from 55.21 to 70.01% while curative activity ranging from 63.51 to 81.78%. Thus, the findings of the research validated the ethnomedicinal claim for the use of H. spicigera in rural areas for malarial therapy. Therefore, isolation and characterization of bioactive compounds responsible for the antimalarial effect of the plant from this work is recommended.