김정원 (분석과학기술대학원)

안현주 (분석과학기술대학원)

김정원 (분석과학기술대학원)

서나리 (분석과학기술대학원)

안현주 (분석과학기술대학원)

Polysaccharides extracted from seaweeds such as alginate and fucoidan possess significant biological and industrial relevance. They have attracted attention in the food and medical fields due to their physiological activities including anti-inflammatory and immunomodulatory effects. However, these marine polysaccharides are more complex and diverse in structure than many polysaccharides from land plants. In addition, their large molecular size and diverse glycosidic linkages make direct analysis of intact polysaccharides challenging. Therefore, controlled depolymerization into oligosaccharide units is an effective strategy for structural elucidation. In this study, we developed a catalyst-assisted depolymerization method based on a Fenton-type reaction under mild conditions coupled with mass spectrometry for structural analysis. This mild and enzyme-like approach eliminates the need for harsh acid treatment and enables efficient, stable depolymerization. We optimized the reaction conditions, including catalyst and hydrogen peroxide levels and reaction time, to ensure effective cleavage with minimal side reactions. Afterthat, the resulting oligosaccharides were rapidly profiled using MALDI-TOF MS. From alginate, we obtained oligosaccharides with degrees of polymerization (DP) ranging from 3 to 8. Fucoidan was also successfully depolymerized into structurally informative oligosaccharides. These results confirm that the developed method is both efficient and selective, yielding high-quality fragments suitable for downstream glycan analysis. In future studies, we plan to extend this strategy to LC/MS for isomer separation and sequence-level characterization of oligosaccharides. Our approach may also prove valuable for the analysis of other complex marine glycans.