Brazilian insulin plant as a bifunctional food: dual high-resolution PTP1B and α-glucosidase inhibition profiling combined with HPLC-HRMS-SPE-NMR for identification of antidiabetic compounds in Myrcia rubella Cambess

Abstract

Six species of Myrcia, commonly known as 'insulin plants' in Brazil, were assessed for their potential as functional foods. Thus, dual high-resolution α-glucosidase/PTP1B inhibition profiling and HPLC-HRMS-SPE-NMR analysis were used to identify the antidiabetic constituents of the crude ethyl acetate extract of M. rubella Cambess. A total of 31 compounds were identified, including seven α-glucosidase inhibitors with IC50 values between 0.6 and 22.4 μM: 4,5-dicaffeoylquinic acid, isoquercitrin, quercetin-3-O-β-d-glucuronide, kaempferol-3-O-(6″-galloyl)-β-d-glucopyranoside, quercetin-3-O-(6″-malonyl)-glucopyranoside, quercetin-3-O-(6″-(E)-feruloyl)-β-d-glucopyranoside, and quercetin-3-O-(2″-(E)-sinapoyl)-glucopyranoside as well as three strong PTP1B inhibitors with IC50 values between 0.4 and 3.1 μM: kaempferol-3-O-α-l-rhamnoside, astragalin, and arjunolic acid. These results show that M. rubella is a potential bifunctional food for management of type 2 diabetes.