PHYTOCHEMICAL AND PHARMACOLOGICAL INVESTIGATIONS OF RHIZOME EXTRACTS OF KAEMPFERIA GALANGAAbstract
Rhizome of Kaempferia galanga (Family: Zingiberaceae) has been investigated for isolation of secondary metabolites and evaluation of bioactivities. Two cinnamic acid derivatives, Ethyl p-methoxycinnamate (KG-2) and 4-methoxy cinnamic acid (KG-9) have been isolated from the chloroform fraction of the methanolic extract of the rhizome of K. galanga using chromatographic analysis. Structures of these compounds were elucidated by extensive spectroscopic analysis and by comparing the data with the published one. In the carrageenan-induced paw edema test, at a dose of 400 mg/kg the methanolic extract, chloroform and n-hexane fraction showed a significant (p<0.05) inhibition of paw edema with 55.08, 48.85 and 71.88 % inhibition after a 2nd hour of the study period. In acetic- acid-induced writhing test, the chloroform and n-hexane extract at a dose of 400 mg/kg showed a significant (p<0.001) reduction in the number of writhes with38.19 and 62.31% writhing inhibition respectively. In hypoglycemic evaluation study by oral glucose tolerance test, all of the extracts at 200 mg/kg body weight inhibited the rise in blood glucose level. After 30 min of a glucose load, the methanolic extract, and chloroform soluble fraction remarkably reduced blood glucose level with 61.2 and 89.63% reduction compared to control which were more prominent than that of glibenclamide (34.78% reduction compared to control. The maximal percentage inhibition of glucose load of n-hexane extract vs. control was 133.33 % which was higher than that of the standard. We reported for the first time that the rhizome of K. galangal showed potential antihyperglycemic activity in mice.
M. Z. Chowdhury, Z. A. Mahmud *, M. S. Ali and S. C. Bachar
Department of Clinical Pharmacy and Pharmacology, Faculty of Pharmacy, University of Dhaka, Dhaka-1000, Bangladesh.
07 December 2013
19 February 2014
28 February 2014
01 March 2014