Objective: Terminalia chebula fruits are used as traditional herbal medicine from the ancient era but still now, the extract has not revealed any research data on CNS depression activity as well as its lyophilized herbal formulation. The present study was designed to evaluate CNS depression activity and develop lyophilized oral cake of Terminalia chebula fruit extract.
Methods: CNS depression potential of Terminalia chebula fruit was examined using the hole board, hole cross, and thiopental sodium induced sleeping time test. The human equivalent dose was calculated based on US FDA guidelines of dose conversion between animals and humans. A novel lyophilized herbal oral cake of aqueous extract of Terminalia chebula fruits with additives was then formulated. The formulated cake was subjected to characterize its physicochemical properties such as appearance, residual humidity, drug content, dissolution, and drug release profile, extract-polymer compatibility by Fourier-transform infrared spectroscopy (FTIR) and stability. The prepared cake was further evaluated with the hole board and hole cross model in mice and compared with control to ensure its CNS depression activity.
Results: Crude extract at the doses of 100, 150, 200, and 400 mg/kg body weight showed significant (p<0.01) dose-dependent inhibition of locomotor behavior. Crude extract dose of 200 mg/kg body weight in mice compared with standard diazepam dose (1 mg/kg) was used to calculate the human equivalent dose of 1000 mg/60 kg. The formulation presented a rapid drug release profile while drug content was approximately 99.5%. FTIR spectroscopy of formulation showed no drug-excipient interaction. The oral cake at the dose of 200 mg/kg body weight showed significant (p<0.01) CNS depression activity.
Conclusion: CNS depression activity, FTIR, and stability analysis ensure the preservation of active ingredients in the lyophilized oral cake as in the crude extract.