No abstract

The methanol extract of stem bark of Detarium microcarpum and Myosortisscorpioides were screened for in vivo safety pharmacological studies (acute toxicity LD 50 ) using Swiss Albino Miceand for the presence of some phytochemicals. The result of the phytochemical screening indicated the presence of important secondary metabolites including alkaloids, saponins, tannins, anthraquinones, carbohydrates, flavonoids. The results showed that the plant extracts were toxic to the mice and caused death at a concentration of =2900mg/Kg and 1600mg/kg body weight of the live mice and LD 50 of 3,807.89mg/Kg and =2,828.43mg/Kg respectively. The result of the study was a useful guide to a practically safe dose in an ongoing antimalarial study of extracts of these plants.

Myosotis scorpioides L commonly called water forget-me-not or true forget-me-not has been claimed by Traditional Medicine Practitioners (TMP) in Adamawa State to cure malaria. It is a herbaceous perennial flowering plant in the borage family (Boraginaceae). The present study was undertaken to scientifically verify the claimed ethnomedicinal use of the plant as antimalarial. The crude powdered sample (whole plant) of Myosotis scorpioides was extracted with methanol in a Soxhlet extractor. The concentrated extract was screened for the presence of secondary metabolites, tested for the median lethal dose (LD50) and antimalarial activity using Swiss albino mice. The result of the phytochemical screening indicated the presence of alkaloids, terpenes, tannins, flavonoids, saponins and anthraquinones. The result of the suppressive test (early malaria infection) showed a significant percentage suppression compared to the control with values of 49.91%, 56.72%, and 65.63% at the doses of 100 mg/kg, 150 mg/kg, and 250 mg/kg, respectively. The result of the prophylactic (residual malaria infection) tests showed a significant level of inhibition compared to the control (43.22%, 52.45%, and 85.70%) for the three doses. The curative (established malaria infection) tests also showed a significant level of parasite suppression compared to the control with percentage suppression of 66.73%, 70.20%, and 73.96% at 100, 150, and 250 mg/kg, respectively. The present study has validated the use of Myosotis scorpioides as remedy to malaria infection by the traditional medicine practitioners in Adamawa, State Nigeria.