Structural Dependence of Sulfated Polysaccharide for Diabetes Management: Fucoidan From Undaria pinnatifida Inhibiting α-Glucosidase More Strongly Than α-Amylase and Amyloglucosidase

Hui Si Audrey Koh; Jun Lu; Weibiao Zhou

doi:10.3389/fphar.2020.00831

Structural Dependence of Sulfated Polysaccharide for Diabetes Management: Fucoidan From Undaria pinnatifida Inhibiting α-Glucosidase More Strongly Than α-Amylase and Amyloglucosidase

Front Pharmacol. 2020 Jun 5:11:831. doi: 10.3389/fphar.2020.00831. eCollection 2020.

Authors

Hui Si Audrey Koh^{1

2}, Jun Lu^{3

4

5

6}, Weibiao Zhou^{1

2

7}

Affiliations

¹ NUS Graduate School for Integrative Science and Engineering, National University of Singapore, Singapore, Singapore.
² Department of Food Science and Technology, National University of Singapore, Singapore, Singapore.
³ Faculty of Health and Environmental Sciences, School of Science, Auckland University of Technology, Auckland, New Zealand.
⁴ Faculty of Health and Environmental Sciences, School of Public Health and Interdisciplinary Studies, Auckland University of Technology, Auckland, New Zealand.
⁵ Maurice Wilkins Centre for Molecular Discovery, Auckland, New Zealand.
⁶ College of Food Engineering and Nutrition Sciences, Shaanxi Normal University, Xi'an, China.
⁷ National University of Singapore (Suzhou) Research Institute, Suzhou, China.

Abstract

Fucoidan refers to a group of sulfated polysaccharide that is commonly obtained from various species of brown seaweed. Fucoidan has gained increased popularity among researchers in the recent years due to its numerous biological activities, including its inhibitory effects against starch hydrolyzing enzymes such as α-amylase and α-glucosidase. This highlights the potential of fucoidan as an antidiabetic agent in the management and prevention of diabetes mellitus. In this study, the inhibitory effects of fucoidan isolated from the New Zealand Undaria pinnatifida seaweed species against three starch hydrolyzing enzymes-α-amylase, α-glucosidase, and amyloglucosidase-was investigated. It was demonstrated that while the fucoidan exhibited significant inhibitory effects against all the three starch hydrolases, it is an uncompetitive inhibitor of α-amylase and amyloglucosidase, and is a competitive inhibitor of α-glucosidase. Moreover, it exhibited significantly stronger inhibitory effects against α-glucosidase than α-amylase, thus having the desirable characteristics as an antidiabetic agent.

Keywords: Diabetes; Undaria pinnatifida; amyloglucosidase; fucoidan; α-amylase; α-glucosidase.