Comparison and Characterization of Polysaccharides From Various Sources and Before and After Honey Processing of Astragali Radix Utilizing Saccharide Mapping

ABSTRACT This study aimed to investigate the differences in polysaccharides in Astragali Radix (AR) from different sources, as well as before and after honey processing, through the analysis of enzymatic hydrolysates. The hydrolysis product of astragalus polysaccharides (APS) by β‐galactosidase was characterized using hydrophilic interaction ultra‐high‐performance liquid chromatography coupled with time‐of‐flight mass spectrometry (HILIC‐UHPLC‐QTOF/MS). The results indicated that all oligosaccharide fragments were composed of hexoses, with sugar groups linked by 1,6‐glycosidic bonds. APS enzymatic hydrolysates fingerprints were established using hydrophilic interaction high‐performance liquid chromatography with an evaporative light scattering detector (HILIC‐HPLC‐ELSD) and comprehensively evaluated based on their similarity. Semi‐quantitative analysis of each enzymatic hydrolysate was performed, combined with partial least squares discriminant analysis (PLS‐DA) and significance testing to further analyze the main differential sugar fragments of AR in different growth modes and before and after honey processing. Glucose and oligosaccharides with degree of polymerization (DP) of 5 and 6 were identified as indicators to distinguish different growth modes. Glucose can serve as an indicator to distinguish raw AR from honey‐processed AR (HAR). This study identified quality evaluation indicators of APS based on saccharide mapping, providing a reference for the development of quality standards for AR.