INTERNATIONAL JOURNAL OF PHARMACY & LIFE SCIENCES Identification and estimation of stevioside in the commercial samples of stevia leaf and powder by HPTLC and HPLC

Stevioside, a major sweet component of leaves of Stevia rebaudiana (Bertoni), is about 300 times sweeter than sucrose. Highly refined stevia leaf extracts and st evioside are officially used as low calorie sweeten ers in many countries. The present study describes a method for rapid identification and estimation of stevioside in commercial samples using HPTLC and HPLC. Identification of stevioside in samples was done by HPTLC. The separation was achieved on a pre-coated silica gel 60F 254 plate with mobile phase; ethyl acetate: methanol: water (75:15:10 v/v/v). Densitometric scanning was perfomed at 510 nm after visualization with a solution of acetic anhydride: sulphuric acid: ethanol (1:1:10 v/v/v). The identity of the p eak corresponding to stevioside was further confirm ed by spectral analysis. HPLC was used for the estimation of stevi oside content. The calibration curve was linear in the concentration range from 0.1 to 1 mg/ml. The detect ion limit for stevioside was 0.05 mg/ml (1 µg per i njection). The percentage stevioside content of the samples i.e. s tevia powder and stevia leaf was found to be; 8.859 % and 3.703 % respectively. The method allows rapid identificat ion and quantification of stevioside in different s amples and can be used for routine analysis of stevioside in comme rcial samples .