Evaluation of phytochemical constituents and sedative-hypnotic activity of the methanol leaf extract of Ficus exasperata in mice

BACKGROUND AND AIM: Sedative drugs mostly cause dose-dependent depression of the central nervous system which results in hypnosis and anesthesia possibly; however, these agents are associated with some side effects ranging respiratory, digestive, immune system dysfunctions, tolerance, cognitive function deterioration, and physical dependence; hence, investigations of newer and safer agents are, therefore, imperative. The current study was aimed at investigating the sedative-hypnotic (S-H) effects of the methanol leaf extract of Ficus exasperata in mice. MATERIALS AND METHODS: Phytochemical screening of the leaf extract was conducted, and S-H activity of the plant extract was evaluated. Twenty Swiss Albino mice were randomly divided into four groups of five mice each. The mice in Groups A and B were injected with the extract intraperitoneally (IP) at the dose rate of 100 and 200 mg/kg, respectively, those in Group C were injected with xylazine at the dose rate of 10 mg/kg, while Group D mice received distilled water at the dose rate of 2 ml/kg. All the four experimental groups were injected with ketamine (IP) at the dose rate of 100 mg/kg after 30 min. RESULTS: Phytochemical analysis of the extract revealed the presence of carbohydrates, cardiac glycosides, reducing sugars, steroids and triterpenes, saponins, tannins, condensed tannins, and flavonoids, while anthraquinones, anthracene derivatives, and alkaloids were absent. Results from the S-H evaluation show no significant difference (p≥0.05) on the onset of sleep time between the four experimental groups; however, statistically significant difference (p≤0.05) was recorded in the sleep duration time between the groups treated with only ketamine and the other experimental groups pre-treated with either the extract or xylazine before ketamine administration. The group pre-treated with a high dose of the plant extract (200 mg/kg) and the treated with ketamine after 30 min exhibited longer sleeping duration time. The plant extract, xylazine and ketamine, sedated the mice for some period of time after arousal from sleep. CONCLUSION: Our finding suggests that methanol leaf extract of F. exasperata possesses S-H potential that may require further scientific investigations.