Analysis of predominant steviosides in Stevia rebaudiana bertoni by liquid chromatography/electrospray ionization-mass spectrometry

Stevia reabudiana is gaining popularity especially in making diabetic food supplements in view of its non-nutritive glycosides. Steviosides profile in ex vitro and in vitro leaves and callus cultures of S. rebaudiana were investigated by HPLC analysis and further confirmed by MS using mass spectral fragmentation data obtained from LC-MS-ESI studies. The leaf samples (4 weeks old) and callus cultures (2 weeks old) were used for extraction and extracts were used for HPLC analysis. Predominantly, eight sweet diterpene glycosides were detected. The highest stevioside content of 6.48% Steviolbioside and 0.099% Rebaudioside-A on a dry weight basis were found in ex vitro and in vitro leaves, respectively. In callus and suspension cultures, the biosynthesis of steviosides was observed except for steviolbioside. The LC-MS-ESI based detection of different steviosides in Stevia cultures could be used for comprehensive qualitative evaluation of the samples.