Extraction of Diterpene Glycoside from Stevia (Stevia Rebaudiana Bertoni)

Leaves of stevia (Stevia rebaudiana Bertoni) are being used as a low calorie sugar substitute in different countries. The sweetness is due to the presence of diterpene glycosides (such as stevioside and rebaudioside) which are completely free of calories making it a natural alternative to synthetic non-nutritive sweeteners. The extract of diterpene glycoside with the help of isobutyl alcohol and crystals were washed with methanol and derived in air circulating oven. The diterpene glycoside was recrystallized by washing with methanol. The extract was characterized by spectroscopic (FTIR) and chromatographic (HPLC) techniques. Diterpene glycoside has different functional groups such as alcohol, alkane, ketone, alkene and ether. HPLC chromatogram retention times (RT) are 9.500 to 9.601 min and 13.948 to 14.000 min corresponding to stevioside and rebaudioside, respectively. The stevioside and rebaudioside were determined to be 32.94% to 58.68% and 24.62% to 29.88% of total extract of diterpene glycoside, respectively.