Isolation, purification, anti-diabetic and antioxidant properties of fucoidan from brown seaweed Sargassum ilicifolium

In the present study, anti-diabetic and antioxidant properties of fucoidan in brown seaweed S. ilicifolium were examined. Initially, pigments, phenolic compounds and low-molecular weight proteins were removed using 80% ethanol and then fucoidan extracted by distilled water at 60 °C for 2h. After fucoidan recovery using 70% ethanol, the fractionation of crude fucoidan was performed by anion-exchange chromatography using DEAE Sepharose FF column. Among crude fucoidan and fractions (F1 and F2), F1 fraction exhibited the highest DPPH radical scavenging (81.28%), ABTS radical scavenging (93.68%) and reducing power activities (0.119 Abs) at 2mg/mL. Besides, F1 fraction exerted the greatest ability to inhibit α-amylase activity (86.16%) at 2mg/mL. Overall, the current findings revealed that fucoidan from S. ilicifolium could be utilized in functional foods as anti-diabetic and antioxidant compounds.