Some behavioural studies on methanol root bark extract of Burkea africana (fabaceae) in mice
Burkea africana is a plant that belongs to then family Fabaceae; it is widely spread in tropical Africa including Nigeria. It is of valuable in ethnomedicine especially in the treatment of antidote for venomous stings and bites, cutaneous and sub cutaneous parasitic infection, convulsion and pulmonary troubles. The research was conducted to evaluate some central nervous system properties of the root bark methanol extractof B. africana in mice. It involved the following animal models: diazepam-induced sleep, hole-board and walking beam assay. Results: The methanol extract showed a significant decrease in the onset of sleep at doses of 40 mg/kg and 80 mg/kg (p<0.05); as well as produced significant increase in the duration of sleep (40 and 80 mg/kg) at p<0.05, p<0.005 respectively. The number of head dips significantly increased at 20 and 80 mg/kg (p<0.05 and 0.005 respectively). From the beam walking test for motor deficits, the result showed a significant increase in the number of foot slips at doses of 20 mg/kg (p<0.05); 40 and 80 mg/kg (p<0.005), where as there was no significant difference in the time taken to cross the two ends of the beam (time taken to complete the task). The median lethal dose (LD50) value of B. africana extract was found to be 288.5 mg/kg (i.p) in mice. The preliminary phytochemical screening revealed the presence of carbohydrates, saponins, flavonoid, aglycones, tannins, anthraquinones, cardiac glycosides, unsaturated steroids and triterpenes. Our results suggest that the B. africana extract contains biologically active compounds with potential sedative and anxiolytic properties.
Key Words: Sedation, B. Africana, Diazepam, ethnomedicine