CONTENTS OF GYMNEMIC ACID IN HEALTH FOODS USING GYMNEMA-SYLVESTRE

Contents of gymnemic acids were investigated in 21 kinds of commercial health foods using Gymnema sylvestre leaves or extract. A hot water e xtract of each sample was acidified and centrifuged. The obtained prec ipitate was dissolved with ethanol and hydrolyzed with alkali followed by acid to hydrolyze gymnemic acid to gymnemagenin. The hydrolyzate w as purified on an ODS cartridge, and gymnemagenin was measured by HPLC . The content of gymnemic acid was calculated as gymnemic acid II. Con tents of gymnemic acid were N.D. (less than 10.5 mu g/g) to 20.5 mg/g for 11 kinds of tablets, 8.46 mg/g for 1 kind of powdered leaves, 2.12 similar to 6.89 mg/g for 5 kinds of tea bags of ''gymnema tea'', N.D. (less than 0.207 mu g/mL) to 4.41 mu g/mL for 2 kinds of soft drinks, and 0.029 similar to 0.055 mg/g for 2 kinds of chewing gum.