Effect of Katsuodashi on postprandial blood glucose levels and identification of dipeptidyl peptidase IV inhibitory peptides among its components

• Main Authors: Yoshifumi Fujiwara, Eiji Seki, Junko Susuki, Takuya Yamane, Iwao Ohkubo
• Format: Article
• Language: English
• Published: Elsevier 2021-10-01
• Series: Clinical Nutrition Open Science
• Subjects: Katsuodashi; Postprandial blood glucose; DPP-IV; Inhibitory peptide; Diabetes; LC-MS/MS
• Online Access: http://www.sciencedirect.com/science/article/pii/S2667268521000322
• ISSN: 2667-2685

Summary: Katsuodashi is a crucial component of Japanese cuisine. In this study, we performed an oral meal tolerance test in humans to investigate the effect of 5% Katsuodashi on postprandial blood glucose levels. Postprandial blood glucose levels were significantly suppressed by 5% Katsuodashi. Thus, 5% Katsuodashi is a functional food that may also be useful for reducing postprandial increase in blood glucose. Furthermore, the dipeptidyl peptidase IV (DPP-IV) inhibitory peptides in Katsuodashi were identified using liquid chromatography-electrospray ionization-tandem mass spectrometry. Ala-Trp and Gly-Trp were found to be the DPP-IV inhibitory peptides in Katsuodashi. Furthermore, Ala-Trp and Gly-Trp demonstrated inhibitory activity against DPP-IV with an IC50 value of 85.91 μg/mL and 363.60 μg/mL, respectively. These results indicate that Katsuodashi may have a beneficial effect on type 2 diabetes.(Trial registration: UMIN000034776, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000039564)