A Systematic Method for the Identification of Oligosaccharide Constituents in Polygonatum cyrtonema Hua Using UHPLC-Q-Exactive Orbitrap Mass Spectrometry

A <i>Polygonatum cyrtonema</i> Hua (PCH) is a common medicinal and edible plant whose rhizomes are widely used for the treatment and prevention of various diseases. Previous studies have revealed a variety of chemical components such as polysaccharides, saponins, and flavonoids, which possess a variety of biological activities such as antimicrobial, lipid-regulating, anti-aging, hypoglycemic, and anti-inflammatory. However, to date, the structure and activity of its oligosaccharide components are still unclear. In this study, we developed a method combining ultra-high-performance liquid chromatography with Q-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap MS) and monosaccharide analysis for the identification of oligosaccharides in PCH. Finally, a total of 44 oligosaccharides, including 27 fructo-oligosaccharides (FOS), 10 arabino-oligosaccharides (AOS), and 7 others, were identified based on the precise relative molecular mass and fragment ion information provided by high-resolution mass spectrometry, in combination with standard comparison, monosaccharide composition analysis, and the relevant literature reports. All of those oligosaccharides were reported for the first time. These findings laid the foundation for the subsequent study of its medicinal substances and provided a theoretical basis for the more comprehensive development and utilization of PCH as a medicinal and edible product.