Study on the Separation, Identification, and Quality Control Methods of Oligosaccharide Components in Wine-Processed Polygonati Rhizoma.

This study aimed to identify oligosaccharide quality markers in wine-processed Polygonati Rhizoma (WPR) and to examine how sugar components change during its repeated steaming and drying, correlating these changes with the color of the processed slices. Seven oligosaccharides were extracted from WPR using water extraction, ethanol precipitation, and preparative liquid chromatography. Identified by NMR with purities above 93%, they were DFA III (1), DFA VII (2), DFA II (3), β-D-Fructofuranose-1,2':2,1'-β-D-Fructofuranose (4), DFA I (5), sucrose (6), and 1-kestose (7). Compounds 1-5 were newly isolated from WPR, and their contents increased post-processing. Measurements of color values, total reducing sugars, and the abundant DFA III and DFA I at different processing stages revealed a progressive darkening of the slices with more steaming cycles, showing a strong correlation between total color difference (Eab*) and sugar component changes. Additionally, DFA III and DFA I levels were much higher in commercial WPR than in raw material, suggesting these difructose anhydrides as potential markers for WPR.