Hypnotic Effect of Ocimum basilicum on Pentobarbital-Induced Sleep in Mice

Sleep disorders are accompanied by several complications, and currently used soporific drugs can induce unwanted effects such as psychomotor impairment, tolerance, amnesia, and rebound insomnia.
The present study was carried out to investigate if Ocimum basilicum has a sleep-prolonging effect.
This work was an experimental study on 72 mice which were randomly divided into 9 groups: saline (control); diazepam (3 mg/kg, positive control); hydro-alcoholic extract (HAE) of Ocimum basilicum (25, 50, or 100 mg/kg); ethyl acetate fraction (EAF, 50 mg/kg); n-butanol fraction (NBF, 50 mg/kg); water fraction (WF, 50 mg/kg); and saline containing 10% DMSO (vehicle for EAF and NBF). All the test compounds were injected intraperitoneally (IP) 30 minutes before pentobarbital administration (30 mg/kg). Duration and latency of pentobarbital-induced sleep were recorded. Also, LD50 of HAE was determined and the cytotoxicity of HAE was tested on neural and fibroblast cells using the MTT assay.
HAE increased the duration of pentobarbital-induced sleep at doses of 25, 50, and 100 mg/kg (P The present data demonstrated that Ocimum basilicum potentiates sleeping behaviors without any cytotoxicity. The main component (s) responsible for the hypnotic effects of this plant is most likely a non-polar agent (s) which is found in NBF. Isolation of the active constituents may yield a novel sedative drug.