Quantitative analysis of fructo-oligosaccharides in Gynura divaricata subsp. formosana by high performance anion exchange chromatography-pulsed amperometric detection.

High performance anion exchange chromatography-pulsed amperometric detection was employed in this study to conduct quantitative analysis of the inulin-related fructo-oligosaccharides present in Gynura divaricata subsp. formosana. Result obtained for the 1-kestose (GF2), nystose (GF3) and 1F-beta-fructofuranosyl-nystose (GF4) contents were 146.60 +/- 0.04, 24.70 +/- 0.75 and 16.60 +/- 0.91 microg/g, fresh weight, and 68.90 +/- 0.02, 7.60 +/- 1.34 and 149.30 +/- 0.06 microg/g (mean +/- RSD), dry weight, respectively. Using this method, the limit of quantitation was 20 microg/mL and the linear detectability between 0-250 microg/mL. The developed method provides a practical analysis for these low caloric value, prebiotic and non-digestible carbohydrates in the genus Gynura.