Rapid screening of potential α-amylase inhibitors from Rhodiola rosea by UPLC-DAD-TOF-MS/MS-based metabolomic method

There is a growing interest in screening α-amylase inhibitors from natural products for application in the development of new anti-diabetic drugs or functional foods. In this study, an UPLC-DAD-TOF-MS/MS-based metabolomic method for rapid screening α-amylase inhibitors from Rhodiola rosea was described. First, Rhodiola rosea preparation (ligand) reacted with α-amylase (receptor) to form ligand-receptor complexes. The complexes were separated by centrifugal ultrafiltration. After that, an UPLC-DAD-TOF-MS/MS-based metabolomic method was used to measure changes in metabolome profile of Rhodiola rosea preparation before and after reaction with α-amylase. As a result, ten corresponding potential α-amylase inhibitors were obtained and identified as epigallocatechin gallate, herbacetin-3-O-d-glucopyranosyl-7-O-l-rhamnoside, kaempferol 3-xylosyl-(1 → 6)-glucoside, berbacetin-8-O-d-glucopyranoside, tricin 7-O-β-d-glucopyranoside, kaempferol 3-glucoside, tricin 5-O-β-d-glucopyranoside, herbacetin-7-O-rhamnoside, kaempferol and tricin. In conclusion, metabolomics is a promising technology to rapidly screen potential anti-α-amylase compounds from natural products.