Isolation and purification of stevioside from stevia leaves

Abstract

Stevia rebaudianaBertoni which has gained industrial and scientific interests is a suitable nutritional alternative to sucrose as a sweetener. Recently, there have been studies which show the extraction of this phytochemical substance from stevia leaves and purification methods by several alcohols and chromatographic methods. However, these methods are not cost-effective. Therefore, an attempt was made to extract and purify ST using inexpensive, scalable and simple techniques where different steps like extraction, electrocoagulation, ion exchange, activated charcoal, vacuum evaporation and butanol wash were used as purification steps. The present study established a new improved technology of extraction of ST from stevia leaves using water as a solvent followed by various purification steps. 496 mg of Stevioside extracted in the form of crystals was obtained from 100 g of leaves which is 10 times more than the reported yield of 54 mg from 100 g stevia leaves in literature. This methodology can be scaled up at the industry level for future large production to meet the huge demand for natural sweeteners.