Biologically Active Principles of Crude Drugs. Antidiabetic Principles of Corni Fructus in Experimental Diabetes induced by Streptozotocin

Abstract

Antidiabetic activity of Chinese prescription "Hachimi-Gan"was studied by using diabetic rats induced by streptozotocin. Changes in water consumption, urine volume, blood and urinary glucose were studied in order to examine the activity. "Hachimi-Gan"exhibited the antidiabetic activity, while the boiling water extract of "Hachimi-Gan"was ineffective. Among the components of crude drugs of "Hachimi-Gan, "the ether extract of Corni Fructus (The seed of Cornus officinalis) was found to be potent for these diabetes rats. Fractionation of the ether extract revealed that ursolic acid showed the antidiabetic activity and oleanolic acid decreased the amount of water consumption and urine volume.