EVALUATION OF ANXIOLYTIC EFFECT OF MELILOTUS OFFICINALIS EXTRACTS IN MICE

Abstract

Objective: Anxiety is one of the most common and serious mental illness affecting humankind and its extensiveness is on the rise at an alarming rate. Anxiolytic substances are highly acclaimed in the ranking of the most utilized drugs by human. The clinical applications of most widely used anxiolytic agents, that is, benzodiazepines are restricted by their undesirable side effects. Therefore, the development of new pharmacological agents for the treatment of this problem is well justified. Among medicinal plants, Melilotus officinalis (yellow sweet clover) has been recommended for relief of insomnia, convulsions, and as nervine tonic in traditional system of medicine. Nevertheless, no pharmacological studies have thus far evaluated its anxiolytic effect. Therefore, the aim of this study was to evaluate antianxiety effect of different extracts of M. officinalis in mice.Methods: The extracts of roots and aerial parts of the plant were prepared according to the polarity, that is, petroleum ether, chloroform, ethanol, and water. The anxiolytic effects of petroleum ether, chloroform, ethanol, and aqueous extract of aerial parts and roots of the plant (50, 100, and 200 mg/kg, p.o) were examined in albino mice using elevated plus maze (EPM) and mirror-chamber models of anxiety. High-performance thin layer chromatography (HPTLC) studies were carried out using toluene: Acetone: Formic acid as mobile phase.Results: Various extracts prepared from roots did not produce significant effect in both the models, whereas the ethanol extract prepared from aerial parts at 100 and 200 mg/kg showed a significant anxiolytic effect as compared to control and standard group. The petroleum ether, chloroform, and water extracts (50, 100, and 200 mg/kg) of the aerial parts of the plant did not produce meaningful effects in this study. HPTLC analysis of the ethanol extract revealed the presence of nine components.Conclusion: These results suggest that the ethanol extract of aerial parts of M. officinalis plant has statistically significant dose-dependent antianxiety activity which can be attributed to the presence of coumarin, and flavonoid compounds in it.