Quantitative estimation of enzymatic released specific oligosaccharides from Hericium erinaceus polysaccharides using CE-LIF

Polysaccharides exhibit multiple pharmacological activities which are closely related to their structural features. Therefore, quantitatively quality control of polysaccharides based on their chemical charac-teristics is important for their application in biomedical and functional food sciences. However, poly-saccharides are mixed macromolecular compounds that are difficult to isolate and lack standards, making them challenging to quantify directly. In this study, we proposed an improved saccharide mapping method based on the release of specific oligosaccharides for the assessment of Hericium eri-naceus polysaccharides from laboratory cultured and different regions of China. Briefly, a polysaccharide from H. erinaceus was digested by b-(1-3)-glucanase, and the released specific oligosaccharides were labeled with 8-aminopyrene-1,3,6-trisulfonic-acid (APTS) and separated by using micellar electrokinetic chromatography (MEKC) coupled with laser induced fluorescence (LIF), and quantitatively estimated. MEKC presented higher resolution compared to polysaccharide analysis using carbohydrate gel elec-trophoresis (PACE), and provided great peak capacity between oligosaccharides with polymerization degree of 2 (DP2) and polymerization degree of 6 (DP6) in a dextran ladder separation. The results of high performance size exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector (HPSEC-MALLS-RI) showed that 12 h was sufficient for complete digestion of polysaccharides from H. erinaceus. Laminaritriose (DP3) was used as an internal standard for quantifi-cation of all the oligosaccharides. The calibration curve for DP3 showed a good linear regression (R2 > 0.9988). The limit of detection (LOD) and limit of quantification (LOQ) values were 0.05 mg/mL and 0.2 mg/mL, respectively. The recovery for DP3 was 87.32 (+/- 0.03)% in the three independent injections. To sum up, this proposed method is helpful for improving the quality control of polysaccharides from H. erinaceus as well as other materials.(c) 2022 The Author(s). Published by Elsevier B.V. on behalf of Xi'an Jiaotong University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Polysaccharides are important for biomedical and functional food applications, but their quantification is challenging due to their complex structure and lack of standards. This study proposes an improved method using saccharide mapping to assess polysaccharides from Hericium erinaceus. The method involves digestion, labeling, and separation of specific oligosaccharides, resulting in accurate quantification. The proposed method can enhance the quality control of polysaccharides, benefiting not only H. erinaceus but also other materials.