Work

Streamlined Synthesis and Immunomodulatory Effects of Ulvan Oligosaccharides from Marine Green Algae

Year: 2025

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Green algae, commonly used as a source of food nutrients, contain ulvan, which is a water-soluble sulfated heteropolysaccharide isolated from Ulva . Ulvan exhibits a range of biological properties, including antitumor, antiviral, anticoagulant, and immunomodulatory activities. Its sugar backbone consists of 1→4-linked disaccharide repeating units, which are categorized as ulvanobiuronic acids (types A 3′S and B 3′S ) and ulvanobioses (types U 3′S and U 2S3′S ). Despite its promising therapeutic potential, the detailed structure–activity relationship of ulvan remains unclear. In this study, an efficient strategy was developed, utilizing orthogonally protected α1→4-linked l -Rha- d -Glc, l -Rha- l -Ido, and l -Rha- d -Xyl derivatives as disaccharide building blocks to synthesize di-, tetra-, hexa-, and octasaccharides of types A 3′S, B 3′S, and U 3′S . The immunomodulatory effects of these compounds were evaluated through cytokine induction experiments. The results revealed that only the B 3′S and U 3′S octasaccharides had a significant influence on the gene expression of IL-1β, IL-6, IL-10, GM-CSF, and G-CSF. This chemical glycobiology approach offers valuable insights into the biomedical applications of marine ulvan oligosaccharides.

Source: Journal of the American Chemical Society

DOI: 10.1021/jacs.5c09759