Determination of polysaccharides composition in Polygonatum sibiricum and Polygonatum odoratum by HPLC-FLD with pre-column derivatization

A high-performance liquid chromatography-fluorescence detection (HPLC-FLD) method was established for the determination of seven monosaccharides in Polygonatum sibiricum and Polygonatum odoratum. The polysaccharides were de-esterified, extracted, hydrolyzed and derivatized with p-aminobenzoic acid (PABA) to obtain fluorescently labeled monosaccharide compounds, which were finally detected by HPLC-FLD. Inertsil ODS-3, C18 chromatographic column (250 mm × 4.6 mm, 5 μm) was used for chromatography. The excitation wavelength (E(x)) was 313 nm, and the emission wavelength (E(m)) was 358 nm. Ethyl acetate extraction reduced the peaks of chromatogram and improved the detection sensitivity than other agents. The established method had high sensitivity, strong specificity, good linear relationship and recovery efficiency. The results showed that the roots and fibrous roots of Polygonatum sibiricum and Polygonatum odoratum contained these seven monosaccharides, and the highest monosaccharide content was mannose. The method of PABA-HPLC-FLD for determination of monosaccharide content in Polygonatum sibiricum and Polygonatum odoratum was sensitive and accurate. The method established in this work provides a feasible analytical tool for the study of polysaccharides, and the findings on polysaccharides from Polygonatum sibiricum and Polygonatum odoratum can provide guidance for the natural medicine industry.