Chemistry and analytical techniques for ent-kaurene-glycosides of Stevia rebaudiana Bertoni - A review

The Stevia genus encompasses about 200 herbs and shrubs species. Stevia rebaudiana, one of the members has gained commercial importance as a natural low calorie sweetener, due to the presence of high con-centration of stevioside and rebaudioside - A (25% to 45% of stevioside content) in the leaves. The major processes involved in the production and quantification of steviol glycosides are extraction, purification and estimation. Various extraction methods have been used for extraction of steviol glycosides in the world. The extraction methods of steviol glycosides mostly differed at the stage of clarification of extracts. The present study is an attempt to summarize the scattered literature and reports on a single podium. Moreover, it also depicts up to date literature regarding numerous extraction, purification and quantitative estimation methods for steviol glycoside