Sargassum sagamianum Extract Alleviates Postprandial Hyperglycemia in Diabetic Mice

In this study, we investigated the postprandial hypoglycemic effect of Sargassum sagamianum extract (SSE) in streptozotocin-induced diabetic mice. Freeze-dried S. sagamianum was extracted with 80% ethanol and concentrated. The inhibition of postprandial hyperglycemia was determined by the inhibitory activity against α-glucosidase and α-amylase as well as the measurement of postprandial blood glucose levels. SSE demonstrated a high inhibitory activity against α-glucosidase and α-amylase. The IC₅₀ value of SSE against α-glucosidase and α-amylase was 0.095 mg/mL and 0.199 mg/mL, respectively, and thus it was significantly more efficacious than the pharmaceutical acarbose (0.115 mg/mL and 0.229 mg/mL, respectively). The postprandial blood glucose levels in the SSE-administered group were significantly lower than those in the control group. Furthermore, the area under the curve significantly decreased following the administration of SSE. These results indicate that SSE can be used as an α-glucosidase and α-amylase inhibitor and can delay the absorption of dietary carbohydrates.