دانلود HPLC determination of stevioside in plant material and food samples

Abstract

An  HPLC  method  for  the  determination  of sweet-tasting stevioside (STS) in the leaves of the plant Stevia  rebaudiana  and  in  some  beverages  (e.g.  tea, orange juice) was developed. The pre-separation procedure consisted of extraction of STS from the plant material  using  boiling  water  and  a  solid-phase  extraction(SPE). Recovery rates of the SPE for the analysed matrices  ranged  from  92.8%  to  97.8%  (for  concentrations of  STS  of  105,  210  and  300µg/ml;  Relative  Standard Deviation  (RSD)≤3.3%).  The  chromatographic  separations  were  realized  using  a  C18  column,  the  mobile phase  consisting  of  methanol  and  water,  and  with  UV detection at 210 nm. The limits of determination of STS were  5µg/ml  for  the  leaf  extracts  and  the  tea  sample and  8µg/ml  for  the  juice  sample.