Analysis of α-Glucosidase Inhibitory Constituents from Acer tegmentosum Using LC-QTOF MS/MS And Molecular Networking

ABSTRACT

This study was conducted to investigate the difference in activity of each part of Acer tegmentosum, for which there are few studies on α-glucosidase inhibitory activity and the compounds contributing to the activity. Among the barks, twigs, and leaves extracts of A. tegumentum, α-glucosidase inhibitory activity of barks extracts was shown the highest inhibition. 6'-O-Galloyl salidroside (1), (-)-epicatechin-3-O-gallate (2), salidroside (3), procyanidin B2 (4) and procyanidin B2-3'-O-gallate (5) were isolated from barks using LC-QTOF MS/MS and molecular networking to identify compounds expected to contribute to high inhibition. The isolated compounds and two in-house compounds, catechin (6) and (+)-epigallocatechin (7) were evaluated for the αglucosidase inhibitory activity. As a result, compounds 1, 2 and 5 showed high inhibitory activity, and all three compounds commonly contain a galloyl moiety. Additionally, Pearson’s correlation analysis showed that compounds 2 and 5 had a strong correlation with α-glucosidase inhibitory activity, and quantitative analysis on each part revealed that barks had the highest content of the three compounds. These results demonstrate that extracts and compounds with a galloyl moiety from barks of A. tegmentosum might be a potential discovery of new drugs for antidiabetic effects.