A novel anti-hyperglycemic sulfated pyruvylated polysaccharide from marine macroalga Hydropuntia edulis

Abstract

Dipeptidyl peptidase is a crucial enzyme that regulates glucose metabolism by degrading incretins, such as glucagon-like-peptide-1, thereby reducing insulin secretion from the pancreatic β-cells. Consequently, dipeptidyl peptidase-IV inhibitors are an important remedial approach to moderate the hyperglycemic pathophysiology. A pyruvylated polysaccharide characterized as [→3)-4,6-O-(1-carboxyethylidene)-β-D-galp-(2SO₃⁻)-(1→4)-3,6-α-L-AnGalp-(2OMe)-(1→], isolated from the marine macroalga Hydropuntia edulis, showed attenuation potential against dipeptidyl peptidase-IV (IC₅₀ 4.44 μM). The structure was elucidated using mass and one/two-dimensional nuclear magnetic resonance spectroscopic analyses of hydrolyzed polysaccharide besides glycosidic linkages obtained from partially methylated alditol acetate derivative. The isolated polysaccharide also revealed potential anti-carbolytic properties against α-amylase/α-glucosidase (IC₅₀ 45–47 μM). The results proved the candidacy of pyruvylated polysaccharide isolated from H. edulis as a potential therapeutic lead against hyperglycemia.

Graphical Abstract

Keywords:

• Marine macroalga
• Hydropuntia edulis
• pyruvylated polysaccharide
• anti-hyperglycemic activity
• dipeptidyl peptidase-IV inhibitor

Acknowledgements

The authors thank the Director, ICAR-Central Marine Fisheries Research Institute (ICAR-CMFRI), and Head, Marine Biotechnology, Fish Nutrition and Health Division, ICAR-CMFRI for facilitating the research. The authors are thankful to the Head, Department of Applied Chemistry, Cochin University of Science and Technology (Kerala State, India) for necessary support. A.T. gratefully acknowledges the Council of Scientific and Industrial Research for financial support.

Authors contribution

Anjaly Thambi: Data curation; methodology; software; spectral data analysis; writing - original draft. Kajal Chakraborty: Conceptualization; funding acquisition; project administration; supervision; writing - review & editing.

Disclosure statement

No potential conflicts of interest were reported by the authors.

Data availability statement

Chromatographic and spectroscopic spectral data are included as supplementary information.

Additional information

Funding

The authors gratefully acknowledge the funding by the Indian Council of Agricultural Research (ICAR, New Delhi, India) (grant ID-MBT/HM/SUB/23).