The impact of sulphated polysaccharides from Ecklonia maxima on carbohydrate hydrolyzing enzymes, muscle glucose uptake and intestinal glucose absorption ex vivo

Abstract

Ecklonia maxima is a rich source of bioactive compounds and has been shown to exhibit several biological activities. However, the antidiabetic potential of sulphated polysaccharide (SP) from E. maxima is yet to be fully explored. This study characterised crude and purified SPs from E. maxima using Fourier-transform infrared Spectroscopy, Ultra Performance liquid chromatography-diode array detector (UPLC-DAD) and Nuclear magnetic resonance spectroscopy. The antidiabetic potential of the SPs was assessed via their effect on carbohydrate hydrolysing enzymes (α-amylase and α-glucosidase), glucose uptake in psoas muscles and intestinal glucose absorption ex vivo. The SPs revealed the presence of glucose, galactose, xylose and galacturonic acid. The crude and purified SPs exhibited strong inhibitory effects on α-amylase and α-glucosidase activity. The SPs significantly increased glucose uptake into yeast cells and psoas muscles. The crude and purified SPs significantly reduced intestinal glucose absorption compared to metformin. The SPs displayed notable potential for glucose uptake in yeast cells and psoas muscle and inhibition of glucose absorption in small intestine. The antidiabetic mechanisms of the SPs could be linked to inhibition of α-amylase and α-glucosidase, reduction of intestinal glucose absorption and increase in glucose uptake into the muscles. SPs from E. maxima exhibit strong antidiabetic potentials and can be explored for the management of type-2 diabetes.