Multi-fingerprint analysis for interpretation of the quality differences in polysaccharides during Dendrobium...

The interpretation of the chemical quality differences during Dendrobium huoshanense (D. huoshanense) traditional processing into 'Fengdou' is critical for scientifically evaluating the medicinal value, optimizing the processing methods, and ensuring the stability and predictability of its efficacy. In this study, the quality differences of polysaccharides during the processing of D. huoshanense were conducted utilizing high performance size exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector (HPSEC-MALLS-RID), nuclear magnetic resonance (NMR) and saccharide mapping based on polysaccharides analysis by using carbohydrate gel electrophoresis (PACE) and high-performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD). The results showed that the concentration of non-starch D. huoshanense polysaccharides (NDHP) rose and exhibited greater stability during the processing. The molecular weight (Mw), molecular weight distribution, cumulative molar mass, radius of gyration (Rz), and monosaccharide composition molar ratio of NDHP did not have significant changes during the processing, and these parameters would be affected by the presence of starch. The NMR investigation indicated that the primary glycosidic linkages of β-1,4-Manp and β-1,4-Glcp, together with the acetyl group substitutions at O-2 and O-3 of 1,4-linked Manp, were unaltered. Additionally, the PACE and HPAEC-PAD profiles of acidic and enzymatic hydrolysates of NDHP were similar. These findings contribute to a deeper understanding of the changes in bioactive polysaccharides during the processing of D. huoshanense into 'Fengdou', providing theoretical support for improving its processing techniques.