Emerging strategies for the activity assay and inhibitor screening of alpha-glucosidase

The high incidence of diabetes mellitus has caused widespread concern around the world, and has quickly become one of the most prevalent and costly chronic diseases. Alpha-glucosidase has been considered as the main target enzyme in the prevention and treatment of type 2 diabetes, and the inhibition of alpha-glucosidase activity can control postprandial blood glucose levels of diabetics and keep blood glucose levels normal. However, most of the current antidiabetic drugs in the clinic have many side effects. Recently, the screening of alpha-glucosidase inhibitors, from natural products, with excellent activity and less side effects has been successfully achieved, which also proposes more requirements and challenges for the approaches of alpha-glucosidase inhibitor (AGI) screening because of the trace level of active compounds in natural products, large-scale sample screening, and complex matrix of natural products. In this review, we comprehensively summarized the available strategies for the assay of alpha-glucosidase activity and AGI screening for the first time, including classic strategies such as high throughput screening methods (e.g. capillary electrophoresis strategies, HPLC/LC-MS strategies), emerging sensing strategies (e.g. colorimetric sensing, fluorescence sensing, electrochemical sensing, and surface plasmon resonance sensing) and other strategies. Finally, future opportunities and challenges in future research are tentatively proposed.