α-Glucosidase and Protein Tyrosine Phosphatase 1B Inhibitory Activity of Plastoquinones from Marine Brown Alga Sargassum serratifolium

摘要: Sargassum serratifolium C. Agardh (Phaeophyceae, Fucales) is a marine brown alga that belongs to the family Sargassaceae. It widely distributed throughout coastal areas of Korea and Japan. S. has been found contain high concentrations plastoquinones, which have strong anti-cancer, anti-inflammatory, antioxidant, neuroprotective activity. This study aims investigate anti-diabetic activity its major constituents through inhibition protein tyrosine phosphatase 1B (PTP1B), α-glucosidase, ONOO−-mediated albumin nitration. ethanolic extract fractions exhibited broad PTP1B α-glucosidase inhibitory (IC50, 1.83~7.04 3.16~24.16 µg/mL for respectively). In an attempt identify bioactive compounds, three plastoquinones (sargahydroquinoic acid, sargachromenol sargaquinoic acid) were isolated from active n-hexane fraction serratifolium. All dose-dependent against in IC50 range 5.14–14.15 µM, while acid showed (IC50 42.41 ± 3.09 96.17 3.48 kinetic enzyme inhibition, sargahydroquinoic led mixed-type whereas displayed noncompetitive-type inhibition. Moreover, dose-dependently inhibited Docking simulations these demonstrated negative binding energies close proximity residues pocket indicating affinity tight capacity towards site enzymes. These results demonstrate may potential as functional food ingredients prevention treatment type 2 diabetes.