Study of sedative activity of different extracts of Kaempferia galanga in Swiss albino mice

BACKGROUND: Kaempferia galanga is an important medicinal plant and has been traditionally used to help restlessness, stress, anxiety, depression etc. in tropics and subtropics of Asia including Bangladesh, India, China, Japan and Indochina. Literature survey revealed that there are very less reports on neuropharmacological activity of this plant. Therefore, the present study investigated the sedative activity of different extracts of rhizome and leaf of Kaempferia galanga. METHODS: The sedative activity was evaluated by using thiopental sodium induced sleeping time, hole cross and open field tests in Swiss albino mice at the doses of 100 and 200 mg/kg body weight per oral (p.o). The acetone extract of rhizome (ACR), as well as petroleum ether fraction (PEF), chloroform fraction (CHF), methanol fraction (MEF) and acetone extract of leaf (ACL) were examined for sedative activity. RESULTS: In the sedative activity study, all the extracts exhibited significant (p < 0.05 and p < 0.001) reduction of onset and duration of thiopental sodium induced sleeping time, reduction of locomotor and exploratory activities in the hole cross and open field tests. In thiopental sodium induced sleeping time test, the chloroform extract of rhizome (200 mg/kg) showed maximum 358.55 % effect in duration of loss of righting reflex, whereas the standard drug Diazepam (2 mg/kg) produced 231.42 % effect. In hole cross and open field tests, maximum 95.09 % and 95.58 % suppression of locomotor activity were observed with the acetonic leaf extract (200 mg/kg) whereas suppression of locomotor activity of the standard drug Diazepam were 71.70 % and 70.58 % respectively. CONCLUSION: The present study indicates that the acetone extracts of rhizome and leaf of Kaempferia galanga including fractions possess central nervous system (CNS) depressant properties which supports its use in traditional medicine. So, the plant may be further investigated to find out for its pharmacological active natural products.