Characterization of seaweed hypoglycemic property with integration of virtual screening for identification of bioactive compounds

Seaweeds have been studied extensively for their nutritional values but their potential nutraceutical application remained underutilized due to uncharacterized bioactive compounds. Here we demonstrated that water extracts of Kappaphycus, Halimeda, Padina and Sargassum were able to improve insulin resistance, reduced hyperglycemia and protect liver and pancreatic tissue from HFD-induced damage in mice, with both Padina and Sargasssum displayed more significant results than the other two seaweeds. A list of potential bioactive compounds was then composed by virtual screening of 276 compounds detected by LC-MS on selected Padina fractions using molecular docking by Surflex-Dock. Further analysis determined punicate as the most potent bioactive compound that inhibits both glucosidase and dipeptidyl-peptidase-4 enzymes. In conclusion, we discovered novel in vivo hypoglycemic activity in Halimeda and several potential alpha-glucosidase and DPP-4 inhibitors in Padina via virtual screening, demonstrating the efficacy of molecular docking to facilitate discovery of novel bioactive compounds.