Preparation and characterization of a dihydromyricetin–sugar beet pectin covalent polymer

A dihydromyricetin (DMY)–sugar beet pectin (SBP) covalent polymer was prepared using an alkaline method for the first time, and its structure and physicochemical properties were characterized. The results showed that the molecular weight, total phenol content, and ABTS radical scavenging ability of the polymer were positively correlated with DMY dosage. The polymer inhibited α-glucosidase in a mixed non-competitive and anti-competitive inhibition manner, and its inhibition performance depended on the total phenol content. Its maximum inhibitory activity was much higher than that of DMY, which was attributed to its strong protein binding capacity. The stability and β-carotene protective effects of the nano-emulsions stabilized with the DMY-SBP polymers were also positively correlated to the total phenol content and were superior to those stabilized by SBP. Therefore, the results obtained in this study may improve our functional understanding of natural polyphenol-polysaccharide polymers and promote the development of new nutraceuticals.