Assessment of sedative and anxiolytic activities of fruit extract of Vitex doniana (black plum)

This research study was aimed at investigating the common folkloric use of Vitex doniana fruit extract for induction of sleep. Extraction of the fruit extract was carried out with 80 %v/v ethanol. Acute toxicity study and qualitative phytochemical screening of the extract were also done. Twenty-five adult mice divided into five groups (n=5) were used for both the anxiolytic study and the phenobarbital-sleeping time analysis tests. Groups I and II served as negative (distilled water 10 ml/kg) and positive (diazepam 1 mg/kg i.p.) controls, respectively. Groups III, IV and V received the extracts of 250, 500 and 1000 mg/kg p.o., respectively. The effect of extract on time spent in and number of entries into the open arms and closed arms when compared to control were noted. The effect on onset and duration of sleep -were also noted. The extract was found to be relatively safe. Secondary metabolites like tannins and flavonoids were present. There was a dose-related significant (p < 0.05) increase in time spent on the open arm and a decrease in time spent on closed arm when compared to the negative control. Dose-related significant (p < 0.05) decrease in time for sleep onset and increase in duration of sleep when compared to negative control were also observed. From the results of this study, the folkloric use of this fruit extract for the induction of sleep and relaxation seem to be justified.