Supercritical CO2 extraction of glycosides from Stevia rebaudiana leaves: Identification and optimization


ERKUCUK A., AKGÜN İ. H. , Yesil-Celiktas O.

JOURNAL OF SUPERCRITICAL FLUIDS, vol.51, no.1, pp.29-35, 2009 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 51 Issue: 1
  • Publication Date: 2009
  • Doi Number: 10.1016/j.supflu.2009.07.002
  • Title of Journal : JOURNAL OF SUPERCRITICAL FLUIDS
  • Page Numbers: pp.29-35
  • Keywords: Supercritical fluid extraction, Stevia rebaudiana, Optimization, Stevioside, Rebaudioside A, Box-Behnken, CARBON-DIOXIDE EXTRACTION, FLUID EXTRACTION, REBAUDIOSIDE-A, STEVIOSIDE, SWEETENERS, BERTONI, METHODOLOGY, ABSORPTION, HUMANS, DESIGN

Abstract

The aim of this work was to optimize the glycoside composition of Stevia rebaudiana leaves using supercritical fluid extraction (SFE). A Box-Behnken statistical design was used to evaluate the effect of various values of pressure (150-350bar), temperature (40-80 degrees C) and concentration of ethanol-water mixture (70:30) as co-solvent (0-20%) by CO2 flow rate of 15 g min(-1) for 60 min. The most effective variables were co-solvent concentration (P < 0.005) and temperature (P < 0.005). Evaluative criteria for both dependent variables (stevioside and rebaudioside A yields) in the model was assigned maximum. optimum extraction conditions were elicited as 211 bar, 80 degrees C and 17.4% which yielded 36.66 mg/g stevioside and 17.79 mg/g rebaudioside A. Total glycosides composition were close to those obtained using conventional water extraction (64.49 mg/g) and a little higher than ethanol extraction (48.60 mg/g) demonstrating challenges for industrial scale application of SFE. (C) 2009 Elsevier E.V. All rights reserved.